ORIGINAL_ARTICLE
ADAPTATION ACCURACY OF TWO DIFFERENT DENTURE BASE MATERIALS FOR THE COMPLETELY EDENTULOUS MAXILLARY ARCH: AN IN VITRO STUDY
Objectives: to compare between adaptation accuracy of metallic denture base and injection-molded denture base for the edentulous maxillary arch. Materials and Methods: Ten stone casts were obtained from duplicating an educational model of a maxillary edentulous arch. The casts were divided into two equal groups; group I received metallic denture bases while group II received denture bases constructed from injection-molded Thermopress. The dentures and their respective casts were sectioned and gap measurements were made in the mid-palatal and crestal areas using a travelling microscope. Results: gap measurements at the mid-palatal areas were significantly higher than those at the crestal areas in both groups. On comparing the two groups, there was no significant difference between the two groups both at the crestal and mid-palatal areas. Conclusions: Metal denture bases and injection molded dentures base show comparable levels of adaptation accuracies and are both suitable alternatives for heat cured PMMA denture bases.
https://edj.journals.ekb.eg/article_76192_4a248ae6099fff611608513647dda8c3.pdf
2017-10-01
3317
3323
10.21608/edj.2017.76192
Nagla
Nassouhy
1
Lecturer of Removable Prosthodontics, Cairo University
AUTHOR
ORIGINAL_ARTICLE
CLINICAL AND RADIOGRAPHIC ASSESSMENT OF IMPLANT OVERDENTURES RETAINED BY DIFFERENT ATTACHMENT SYSTEMS
Objectives: To compare two different attachments for implant overdentures; ball attachment with nylon matrix and OLS attachment with PEEK matrix regarding bone height changes and implant stability. Materials and Methods: Ten completely edentulous patients were selected and two implants were inserted in the interforaminal region for each patient. After 3 months of installation, the patients were divided into two equal groups; group I receiving overdentures retained with ball attachments and group II receiving overdentures retained with OLS attachments. Implant stability was measured using Periotest and digital radiography was used for bone height assessment at time of prosthesis insertion and at 6, 12 and 24 months later. Results: No significant difference was found regarding Periotest values and bone loss at all follow-up appointments for both groups. There was also no difference between the two groups regarding Periotest values and bone loss at all follow-up appointments. Conclusions: Comparable performance of the two attachments was observed regarding both Periotest values and bone loss at 6, 12 and 24 months of function.
https://edj.journals.ekb.eg/article_76193_76f68fa9f14c9d83cacda396c3f38c98.pdf
2017-10-01
3325
3333
10.21608/edj.2017.76193
Nada
El Khourazaty
1
Lecturer of Removable Prosthodontics, Cairo University
AUTHOR
Nagla
Nassouhy
2
Lecturer of Removable Prosthodontics, Cairo University
AUTHOR
ORIGINAL_ARTICLE
CORRELATION BETWEEN BITING FORCE AND MUSCLE ACTIVITY ACCORDING TO IMPLANT POSITION IN LOWER CLASS I KENNEDY PARTIAL DENTURE
Purpose: The placement of dental implants in a distal RPD extension provided more stable and reliable occlusion. The target of this trial was to investigate the degree of correlation between the maximum biting force and surface electromyography of masseter fibers and anterior fibers of temporalis in two different implant positions in lower Kennedy class I Material and methods : Fourteen patients having lower Kennedy class I with the first premolar as the last abutment and completely dentulous maxilla were randomly divided into two equal groups to receive implant supported partial overdenture. Each group received posterior bilateral two implants in the second molar area in the first group, while the group 2 one in the second premolar area. Right and left Maximum biting force was measured for both groups using I loadstar sensor and masseter and anterior temporalis muscle activity were evaluated with Surface ElectromyographyResult : The data revealed that group I had significant positive correlation between maximum biting force and the masseter and anterior temporalis muscles activity in both the right and the left side with r value (1 , 0.79 , 0.89 and 0.75) respectively on the other hand the group II showed no significant positive correlation with r(0.04,0.01.-0.04 and -0.11) respectivelyConclusion : Within the limitation of this clinical trial, it was concluded that there were better muscle coordination between the two largest muscles of mastication (masseter and temporalis) and the produced biting force as a product due to installation of posterior implant in the lower second molar area.
https://edj.journals.ekb.eg/article_76194_91e5f4ed1884403898deda659c16eddc.pdf
2017-10-01
3335
3342
10.21608/edj.2017.76194
Lower Kennedy class I
Implant supported partial overdenture
biting force
muscles activity
Noha
Nawar
1
Associate Professor of Removable Prosthodontics, Faculty of Dentistry, Ain Shams University.
AUTHOR
Nora
Sheta
2
Lecturer of Removable Prosthodontics, Faculty of Dental Medicine, Cairo University
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF DIFFERENT DENTURE BASE MATERIAL ON THE SUPPORTING STRUCTURE OF PARTIALLY COVERAGE MAXILLARY IMPLANT RETAINED OVERDENTURE
Objectives: This research was carried out to evaluate radiographically the effect of different denture base materials “poly methyl methacrylate base (PMMA) processed by conventional technique versus thermoplastic biocompatible (Polyan IC) base processed by injectable mold technique on the prei-implant bone height changes of partially palatal coverage mucosal-implant retained maxillary overdenture.Materials and Methods: Totally, fourteen completely edentulous participants were equally assigned into two groups (G1 and G2). Each group has received four implants (3mm diameter and 12 mm length), two in the lateral region, and two in the first premolar region. All the participants received partial palatal coverage complete implant overdentures retained by four O-rings. G1 participants have received PMMA denture base processed by conventional method. G2 participants have received Polyan IC denture base processed by using injectable mold. In this Study, crestal bone height changes around each implant were evaluated at time of prostheses insertion, six month and one year later using CBCT. Results: In this study, at the end of follow up period, there was statistically significant difference in the marginal bone height loss between the two groups. The least bone loss was reported around the implants in group 2. After six months, the mean difference of bone height loss were (0.65±0.14) and (0.33±0.09) while from six to twelve month, the mean difference of bone height loss were (0.37±0.11) and (0.20±0.08) in group 1 and group 2 respectivelyConclusion: Within the limitation of this study, it was concluded that Polyan IC denture base processed by using injectable mold may yield more predictable bone/implant interface and may ensure well fitted denture base compared to PMMA denture base processed by conventional method, when partially palatal coverage mucosal-implant retained maxillary overdenture were used.
https://edj.journals.ekb.eg/article_76196_4cb8449c542e3f7cdabc71781182fcd2.pdf
2017-10-01
3343
3349
10.21608/edj.2017.76196
dental implant
maxillary
overdenture
palatal coverage
and marginal bone height
Nora
Sheta
1
Lecturer of Removable Prosthodontics, Faculty of Dentistry Cairo University.
AUTHOR
Shaimaa
Lotfy
2
Lecturer of Removable Prosthodontics, Faculty of Dentistry Ain Shams University.
AUTHOR
ORIGINAL_ARTICLE
CHEMICAL AND MORPHOLOGICAL ANALYSIS OF HUMAN DEMINERALIZED ENAMEL SURFACE BY ACID AND LASER ETCHING FOLLOWING REMINERALIZATION BY MI PASTE PLUS
Objectives: The aim of the present study was to evaluate the effects of remineralizing agent (MI Paste Plus) on the surface topography and chemical analysis of sound human enamel following acid-etching and laser etching, using Environmental scanning electron microscopic (ESEM) techniques.Materials and Methods: Fifty human upper premolars extracted for orthodontic reason were used. The teeth were mounted vertically in a self-cure acrylic cylinder. One clinician prepared all the teeth, in each tooth; a 4x4 mm area was treated in middle third of the buccal surface. The teeth were divided into three groups, Group I : Control group no treatment ; Group II: enamel etched with 37% phosphoric acid; Group III: enamel was irradiated with Er,Cr:YSGG laser. Group II and III were subdivided into subgroup according to remineralizing agent (GC MI Paste Plus), (n=10). Remineralizing paste was used as manufacturer’s instructions, a single application of approximately 0.5 mm layer for 3 minutes; twice daily. Synthetic saliva was rinsing between remineralizing paste application, followed by synthetic saliva rinsing for 15 days with fresh replenished on a daily basis. Teeth were examined for morphological and chemical characterization using an Environmental Scanning Electron Microscope. All of the data were analyzed by two-way analysis of variance (ANOVA) and Tukey’s post hoc test. Results: Morphological changes of enamel surfaces of acid-etching group showed type 1 etching pattern and laser etching group showed the normal appearance of the enamel prisms (honeycomb-like structure). Comparison of all groups and control group P & Ca weight%, the greatest mean value was recorded in acid etch group before and after remineralization with GC MI Paste Plus. Conclusion: Within the limits of this in vitro study, Since Ca and P constitute the major part of tooth structure, while other element represent trace element; results emphasize the effect of GC MI Paste Plus on tooth remineralization. Comparison of all groups and control group, acid etch group before and after remineralization recorded the greatest mean value for P & Ca weight%. Laser etching didn’t have a significant effect on tooth composition and mineral content.
https://edj.journals.ekb.eg/article_76197_9c4e8b3d3d026b069e41c757f9518f4b.pdf
2017-10-01
3351
3359
10.21608/edj.2017.76197
Sahar
Abd El Halim
1
Assistant Professor, Operative Dentistry Department, Misr University for Science and Technology, Egypt.
AUTHOR
Rasha
Raafat
2
Lecturer of Conservative Dentistry, Faculty of Dentistry, Cairo University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
MICRO-CT EVALUATION OF ADAPTATION AT TOOTH/RESTORATION INTERFACE USING THREE RESIN COMPOSITE RESTORATIONS PLACED WITH DIFFERENT FILLING TECHNIQUES
Aim of the study: This study aimed at evaluating the internal adaptation in terms of percentage of contact using micro-CT (μCT) for three resin-based composite restorations placed with different filling techniques.Materials and methods: Three resin-based composites were investigated in this study: Low shrinkage resin-based composite applied incrementally FiltekTM P90, Bulk-fill resin-based composite Tetric EvoCeram® Bulk Fill and Sonic Fill composite (Kerr corp. USA) packed using Sonic Fill handpiece. Fifteen maxillary 1st premolars were collected. A Class II mesio-occluso-distal cavity was prepared on each tooth. After a matrix was applied, all resin composites were used according to their manufacturers’ instructions then light cured. Scanning of the specimens was performed using a μCT machine. The percentage of contact (%) for each sample was done by measuring the length of restoration margin and dividing it by the entire length cavity walls in gingival, middle and occlusal μCT sections and calculating their average in percentage. Data was collected and statistically analyzed.Results: Percentage of contact of P90 to their cavities’ walls was significantly higher than that of TEC BE which was in turn significantly higher than that of SF. There was no significant difference in percentage of contact of P90 and TEC BF to different parts of their cavities. Percentage of contact of SF was significantly higher in occlusal and middle thirds of their cavities than to the gingival third. Adaptation of P90 to different parts of their cavities was significantly higher than adaptation of SF to the corresponding parts.Conclusions: Bulk fill TEC BF and SF composites did not improve percentage of contact compared to low shrinkage silorane based incrementally placed P90 composite. Furthermore, no difference in adaptation of P90 and TEC BF composites to different parts of cavities, however, adaptation of the SF to the occlusal parts of cavities was much better than to gingival parts.
https://edj.journals.ekb.eg/article_76246_4eff62dc25ba40293a30ff1330b05417.pdf
2017-10-01
3361
3370
10.21608/edj.2017.76246
Micro-CT
adaptation
resin composites
filling techniques
Ihab
Moussa
1
AUTHOR
Mostafa
Abdellatif
2
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF IMPLANT ASSISTED PROSTHESIS RESTORING FLABBY MANDIBULAR RIDGE (CBCT STUDY)
Background: The poor quality denture bearing area caused by displaceable flabby tissue is one of the soft tissue abnormalities that commonly encountered in the clinical practice. Surgically or non-surgically, techniques have suggested circumventing this difficulty. Aim: This study aimed to evaluate the management of anterior flabby tissues of completely edentulous mandible using dental implant with either conventional functional impression or selective pressure impression technique.Methods: Twelve completely edentulous patients with anterior mandibular flabby tissues were included in this prospective clinical study. All patients received upper complete denture and lower complete implant assisted overdenture constructed over two implants, placed at the canine region. Patients were randomly divided into two groups. Group I, patients received their overdenture constructed from conventional functional impression technique, while patients of group II received the overdenture constructed from selective pressure impression technique. All patients underwent cone-beam computed tomography scanning at insertion, six and twelve months to measure the amount of marginal bone loss around the implants and the thickness of anterior mucosa between the two implants. All data are collected, tabulated and statistically analyzed.Result: dentures constructed over dental implant for the two groups resulted in marginal bone loss around implant and decrease in flabby tissue thickness at all follow up period at denture insertion, six months and twelve months. When comparing between the two groups at the same follow up period, the patients receiving dentures constructed with selective pressure impression technique resulted in less marginal bone loss and more decrease in soft tissues thickness than those dentures constructed with conventional functional impression techniquesConclusion: Using dental implant is recommended as a way for flabby tissues management. While, using implant with selective pressure impression technique is an effective manner for flabby tissues management than using dental implant alone.
https://edj.journals.ekb.eg/article_76249_187d90fa6541a3d66d4cfd7dfe9c8878.pdf
2017-10-01
3371
3383
10.21608/edj.2017.76249
Displaceable tissues- Implant retained overdenture- Selective pressure impression technique- Cone Beam Computed Tomography
Faten
Abu Taleb
1
Assistant Prof of Removable Prosthodontics, Prosthodontic Department, Faculty of Dentistry, Tanta University.
AUTHOR
ORIGINAL_ARTICLE
IMPACT OF VARIOUS RESIN ADHESIVE STRATEGIES ON MICRO SHEAR BOND STRENGTH TO SOUND, CARIES- AFFECTED AND REMINERALIZED DENTIN SUBSTRATES: AN IN-VITRO ESEM ANALYSIS
Objectives: The aim of this in vitro study was to evaluate the micro shear bond strength of different adhesive system strategies to sound, artificially caries affected and remineralized dentin substrates.Materials and Methods: Sixty bovine permanent incisors were used. The labial enamel was removed and a flat dentin surface was obtained. The dentin specimens were divided into three main groups (sound as a control, artificial caries affected and remineralized dentin groups). Four adhesive systems were applied over the different dentin substrates according to the directions of the manufacturers; (Futurabond M+, Single bond universal (universal adhesives used in self-etch mode, Futurabond DC (Dual- curing self etch bond with nanofillers and Solobond M (Etch and rinse adhesive). After preparation of the 240 micro tubules of resin composite (Filtek TM Z350XT (Flow able restorative), micro shear bond strength test was performed. The results were tabulated and statistically analyzed. Failure mode was detected for all the fractured dentin specimens using the stereomicroscope. ESEM evaluation was done for resin dentin interfaces for all types of adhesives.Results: There was a statistically significant effect of dentin substrate, while the adhesive system type was not. One way ANOVA followed by Tukey HSD post hoc test showed that, the remineralized dentin recorded the highest micro shear bond strength value with Single Bond Universal followed by Futurabond M+. The artificial caries affected dentin showed the highest micro shear bond strength value with Solobond M followed by Futurabond DC, which also recorded the lowest micro shear bond strength result with remineralized dentin.Conclusions: 1- Performance of the tested adhesives strategies was shown to be dentin-dependant.2- Dentin pretreatment with CPP-ACPF containing paste affects positively the micro-shear bond strength of Single bond universal and Futurabond M+ universal adhesives when used in self-etch mode.3-The specific chemical formula of the tested resin adhesives might coordinate with the demineralized dentin.
https://edj.journals.ekb.eg/article_76258_2d971b1963ad138ba35aa47959e9ee56.pdf
2017-10-01
3385
3401
10.21608/edj.2017.76258
Artificial caries affected dentin- Remineralized dentin- Universal adhesive-micro shear bond strength
Omaima
Ghallab
1
Associate Professor of Operative Dentistry, Faculty of Dentistry, Ain-Shams University, Cairo, Egypt.
AUTHOR
Heba
Abd-Elaal
2
Lecturer of Operative Dentistry, Faculty of Dentistry, Ain-Shams University, Cairo, Egypt.
AUTHOR
Dina
Abd-Elkhalik
3
Lecturer of Oral Biology, Faculty of Dentistry, Ain-Shams University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF NANO-SILVER IRRIGATING SOLUTION ON POST-OPERATIVE PAIN FOLLOWING SINGLE VISIT ENDODONTIC THERAPY: A PROSPECTIVE RANDOMIZED CLINICAL TRIAL
Objective: The purpose of this study was to compare the effect of nano-silver (Nanotech Egypt for photo Electronics, Cairo, Egypt) irrigating solution versus sodium hypochlorite on post-operative pain after single- visit endodontic therapy.Methods: A randomized controlled clinical trial was designed and carried out in the endodontic department at Cairo University. Fifty healthy patients with asymptomatic necrotic teeth that were scheduled for non-surgical root canal treatment were enrolled. Single- visit root canal treatment was performed using ProTaper Universal (PTU; Dentsply Maillefer, Ballaigues, Switzerland) rotary files and for irrigation NaOCl 5.25% (Egyptian Company for household products under license of Clorox. Co. Cairo, Egypt) (control group, n=25) and nano-silver irrigating solution (intervention group, n=25) were used. After obturation, post-operative pain was assessed using a visual analogue scale (VAS) after 4, 24, and 48 hours. Chi-square test was used to compare VAS values between tested groups within each follow- up period and Wilcoxon signed rank test was used for within group comparisons over time. Results: Insignificant differences between NaOCl group and nano-silver group were found in pain scores for each follow-up period. The pain score decreased significantly after 24 hours (p=0.003) and after 48 hours (p=0.001) in intervention group. Control group showed similar results were the pain score decreased significantly after 24 hours (p=0.008) and after 48 hours (p=0.001). Conclusion: Both tested irrigants were associated with a decrease of postoperative pain over time, in patients undergoing single-visit endodontic treatment with necrotic pulps. There was no statistical significant difference between both groups.
https://edj.journals.ekb.eg/article_76259_d5797589714ee53cfc310f9c8b602bf2.pdf
2017-10-01
3403
3412
10.21608/edj.2017.76259
Sodium Hypochlorite
nano-silver irrigation
Pain
Postoperative
single-visit
Alaa
El-Baz
1
Associate Professor, Endodontic Department, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
Geraldine
Ahmed
2
Associate Professor, Endodontic Department, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
ORIGINAL_ARTICLE
THE ACCURACY OF IMPLANT POSITIONING USING BONE SUPPORTED VERSUS MUCOSA SUPPORTED SURGICAL GUIDE TEMPLATES FOR IMPLANT ASSISTED LOWER COMPLETE OVERDENTURE
Purpose: Evaluation of the accuracy of implants position using two different types of computer-aided design/computer-aided manufacturing (CAD/CAM) surgical guides, including bone supported and mucosa supported guided templates. Materials and methods: Twelve completely edentulous patients were selected for this study and divided into two groups six each. all patients received a radiopaque radiographic template. A cone beam computed tomography was taken to simulate the position of the two implants, virtual implants were drawn in its place, fabrication of surgical guide template using rapid prototyping technique to match the position of virtual implant according to patient’ group. Group I bone supported surgical guide(BSG) and group II mucosa supported surgical guide (MSG). The implants were installed for each patient using surgical guide templates according to the group. The positions and angulations of the placed implants in comparison to those of the planned ones were determined using special software that matched pre- and postoperative computed tomography (CT) images, and deviations were calculated and compared between the two guide templates using a software program to detect any difference in linear and angular deviation. Data were collected; tabulated and analyzed using student T test. Results : There was no significant difference of both linear and angular measurements between virtual and the surgically placed implants for both groups. Also there was insignificant difference in accuracy between group I (bone supported) and group II (mucosa supported). Conclusions: Using template-guided surgery enables the clinician to optimize implant position, angle, diameter and length by dictating the drilling position and angulation. Cone beam CT has accurate measurements in distances between two implants as clinical measurements. The bone supported surgical guide as well as the mucosa supported surgical guide has the same accuracy in implant positioning.
https://edj.journals.ekb.eg/article_76260_032299a33ded850285a234f7e7f0bcd8.pdf
2017-10-01
3413
3425
10.21608/edj.2017.76260
dental implant
Cone beam computed tomography
computer-aided design/computer-aided manufacture
bone-supported surgical guide
mucosa-supported surgical guide
Faten
Abutaleb
1
Assistant Prof of Removable Prosthodontics, Prosthodontic Department, Faculty of Dentistry, Tanta University
AUTHOR
Hesham
Borg
2
Lecturer of Removable Prosthodontics, Prosthodontic Department, Faculty of Dentistry, October 6 University
AUTHOR
Mahmoud
EKhalifa
3
Assistant Prof. Oral and Maxillofacial Surgery, Faculty of Dentistry,Tanta university, Egypt
AUTHOR
Rafic
Bader
4
Lecturer of Oral and Maxillofacial Surgery, Faculty of Dentistry,Tanta University, Egypt
AUTHOR
Mohamed
Allam
5
Lecturer of Oral and Maxillofacial Surgery, Faculty of Dentistry,Tanta University, Egypt
AUTHOR
ORIGINAL_ARTICLE
PHYSICOCHEMICAL PROPERTIES OF SILICATE BASED BIOMATERIALS
Aim: The purpose of this study was to compare solubility, pH, calcium ion release and setting time of Biodentine, Bioaggregate, and Bioactive glass. Materials and Methods: For the weight loss, pH changes and calcium ions release, the tested specimens were immersed in distilled water. The evaluations were performed at 1h, 24h and 7 d. The measurement of pH was done using digital pH meter. The measurement for Ca2+ ions release was done using atomic absorption spectrophotometry. The setting time was measured by using a Vicat apparatus. Data were analyzed by One Way ANOVA test and the Tukey post-hoc test at P ≤ 0.05.Results: Biodentine showed the greatest solubility, ultimate increase in pH, and highest calcium ion release at all time intervals and the shortest setting time. Bioactive glass showed alkalinity and moderate Ca2+ release after 1 h that were decreased by time. It also showed negative solubility. Conclusions: Biodentine and Bioaggregate favored proper physico-chemical properties except for solubility it was questionable. Bioactive glass is the best regarding solubility.Keywords: Bioactive glass, Bioaggregate, Biodentine , Physico-Chemical properties.
https://edj.journals.ekb.eg/article_76261_3eb3c2fd78f97c009ddb3e62b6e33d8b.pdf
2017-10-01
3427
3434
10.21608/edj.2017.76261
(1) All materials tested recorded a favorable high pH and Ca2+ release. (2) Although Biodentine and Bioaggregate showed high solubility
Bioactive glass showed a negative one. (3) Biodentin has the shortest setting time
Dalia
Fayyad
1
Associate Professor of Endodontics, Faculty of Dentistry, Suez Canal University.
AUTHOR
ORIGINAL_ARTICLE
FREE HAND VERSUS PARTIAL LIMITING DESIGN COMPUTER GUIDED SURGICAL STENT (VITRO STUDY)
Aim of the study: Was to compare the accuracy of two different surgical techniques; free hand and partial limiting, regarding the accuracy of implant position.Materials and methods: Four edentulous dummy mandible simulating human edentulous mandible were used (the model material duplicates type II~III hardness). A surgical stent was fabricated. The surgical stent was secured on the first and second mandibles and all the implants were placed using the partial limit technique; where the initial drill was used first using the stent. The subsequent drills were used free hand. The same stent was placed on the other two mandibles where the position of the implants was delineated using a marker, then the implants were placed free hand. The angles between the long axis of preplanned and real implants were recorded from both the preoperative implant plan & the post-operative implant representations on the resliced CBCT image & were compared to each other in degrees. The linear deviation of the post-operative placement was recorded in mm in coronal & apical positions from the pre-planned implants in both Mesio-distal & Bucco-lingual aspects, also the vertical linear deviation (deviation in depth), was recorded apically, taking the pre-operative implant plan as the reference by the aid of the software matching function.Results : The data was collected and statistically analyzed. The mean angular deviation for group A the free hand was 3.71 ± 2.58 degree while that for group B partial limiting was 1.72 ± 1.67 degree, this difference was statistically significant P0.05. There was statistical significance difference between both groups concerning the angular deviation, Bucco lingual deviation and Mesio distal deviation, while apical deviation was not significantly different.Conclusion: Partial limiting surgical stent is more precise than free hand surgical technique concerning the angular deviation, Bucco lingual deviation and Mesio distal deviation. There is no statistical significant difference concerning apical position.
https://edj.journals.ekb.eg/article_76262_21c0e5fba7fd850f62c3fa11bb319ffa.pdf
2017-10-01
3435
3445
10.21608/edj.2017.76262
Mahmoud
El Homossany
1
Lecturer Removable Prosthodontics Department, Faculty of Dentistry, Ain Shams University.
AUTHOR
ORIGINAL_ARTICLE
STRESS ANALYSIS OF TWO DIFFERENT ATTACHMENTS FOR A TWO IMPLANT RETAINED MANDIBULAR OVERDENTURE
Background: Implant overdenture retained by two implants installed in the interforaminal area of the completely edentulous mandible has become the standard of care for completely edentulous patients. Various attachments have been used to retain a mandibular implant retained over denture, the ball attachment has been the most commonly used un-splinted attachment to retain a mandibular overdenture owing to its low cost and simplicity. A newly introduced attachment made from polyetherketoneketone (PEKK) which have reported to have high chemical and mechanical resistance to wear and high tensile, fatigue and flexural strengths. The aim of this in vitro study is to analyze the distribution of stresses around the two installed implants in the inter-foraminal area of a completely edentulous mandible using strain gauges utilizing an implant retained overdenture with two different types of attachments one with a nylon cap and the other with a PEKK cap.Materials and Methods: A clear heat cured acrylic completely edentulous mandibular model has been used in this in vitro study to fabricate a lower conventional acrylic denture following conventional steps. In the canine region bilaterally two dummy implants were installed and attached to the model using self-cure acrylic resin. The acrylic resin was prepared around each implant into a box shape with a thickness of 1mm into four surfaces; buccal, lingual, mesial and distal. Strain gauges of length 5mm, resistance of 120.4±0.4 Ω and a gauge factor of 2.09 ± 1 %, were attached to each surface. The same lower acrylic denture was used for pickup of the two attachments; the ball and CMLOC attachment. The implant retained overdenture retained by the each attachments was subjected to unilateral and bilateral vertical static load of 100N using a universal testing machine. The wires of the strain gauges were connected to the strain meter to record the micro-strain using a special software, 10 readings were recorded for each attachment. Results: when the implant retained overdenture have been subjected to unilateral loading, the loading side have recorded a higher statistically significant mean micro-strain than the unloaded side retained by both attachments, The overdenture retained with ball attachment have shown a significant increase in micro-strain on the loaded side than that with the CM LOC attachment, while for the unloaded side the overdenture retained with CMLOC attachment induced more micro strain than the ball attachment. While during bilateral loading, a statistically significant higher mean micro strain was recorded in the left implant than the right implant, and the CM lOC have shown a higher statistically significant mean micro strain than the ball attachment for the left implant , while the ball attachment have shown a statistically significant increase in micro strain for the right implant. Conclusion: The newly introduced attachment the CM LOC tends to show a better performance with regards to the micro-strains induced around the implants and also regarding improving the stability of the denture, On the other hand the ball attachments despite having induced more micro-strain around the implants, it could have a higher retention than the CM LOC attachment. Further studies comparing the retention of the new attachment CM LOC and the ball attachment has to be carried out to confirm the conclusion of the present study.
https://edj.journals.ekb.eg/article_76263_594d213d8b9693fe1242aab227ed2f81.pdf
2017-10-01
3447
3457
10.21608/edj.2017.76263
Amr
Rady
1
Lecturer of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
Nouran
Nabi
2
Lecturer of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
ORIGINAL_ARTICLE
A NEW DEVICE MEASURES RETENTION CLINICALLY FOR IMPLANT RETAINED OVERDENTURE
This article describe a new device that can be used for clinical measurement of retention for implant retained overdenture. This device overcomes the problems of the used techniques in terms of vertical direction of force. The force will be perpendicular to the patient’s occlusal plane. The method allows also complete standardization between time intervals.The device consists of plate form with vertical arms and middle screw that move vertically to guide the movement of the force meter in vertical direction. A fork is used to connect the force meter to the implant retained prosthesis through four hooks to canine and first premolar areas bilaterally moving it completely vertical.
https://edj.journals.ekb.eg/article_76264_1e375f5df4812dd66553d98ad6761769.pdf
2017-10-01
3459
3462
10.21608/edj.2017.76264
Mohammed
Raafat
1
Clinical Demonstrator of Removable Prosthodontics, Faculty of Dentistry, Mansoura University.
AUTHOR
Mostafa
Elsyad
2
Associate Professor of Removable Prosthodontics, Faculty of Dentistry, Mansoura University.
AUTHOR
ORIGINAL_ARTICLE
APICAL CLEANLINESS AFTER REMOVAL OF TOTALFILL BIOCERAMIC SEALER VERSUS AH-PLUS EPOXY-RESIN SEALER
Objectives: The aim of the present study was to evaluate the apical cleanliness following canal enlargement after removal of canal obturating material containing TotalFill bioceramic Sealer as compared to AH-Plus epoxy-resin sealer. Materials & Methods: 40 obturated single-canal roots were divided into 2 groups; AH-Plus (Gp-I) and TotalFill (Gp-II) 15 specimen each. 5 specimens were kept as control for each group. Canal filling was removed and canals were enlarged. According to the file size used for canal enlargement, each group was divided into 3 sub-groups; A, B, and C (#30-0.04%, #35-0.04, and #35-0.04%, respectively). Roots were split and the apical third was examined under SEM. Digital image analysis was done for the photomicrographs. Results: SEM images of the control groups revealed more condensed and widely spread particles of TotalFill in comparison to AH-Plus. In AH-Plus subgroups: The recorded means (in a descending order) of remnants for subgroups I_A, I_B, and I_C were 27.3, 24.23, and 0.94, respectively. There was a significant statistical difference (P≤0.05) between the test subgroups, except for subgroups I_A/I_B where the difference was statistically insignificant (P > 0.05). In TotalFill subgroups: The recorded means (in a descending order) of remnants for subgroups II_A, II_B, and II_C were 48.16, 39.3, and 30.42, respectively. There was a statistically insignificant difference (P > 0.05) between the test subgroups, except for subgroups II_A/II_C, where the difference was statistically significant (P≤0.05). In file #40 sub-groups: There was a statistically significant difference (P≤0.01) between the recorded amount of remnants between AH-Plus and TotalFill subgroups. TotalFill recorded higher amount of remnants. Conclusions: Within the parameters of this study - after canal desobturation -, increasing the size of the apical preparation – within limits – improves the cleanliness of canal walls at the apical third area. TotalFill sealer leaves more remnants on the dentin surface of the apical third when compared to AH-Plus sealer. It’s better to enlarge the apical third of the canal two or three sizes larger than the master apical file (in case of desobturation of bioceramic-sealer-containing canal filling) to ensure better cleanliness of the area.
https://edj.journals.ekb.eg/article_76265_960b83a7514e5a8d587bd0d2fcd1aa92.pdf
2017-10-01
3463
3472
10.21608/edj.2017.76265
Apical preparation
apical cleaning
bioceramic sealer
epoxy resin sealer
TotalFill
AH-plus
retreatment
Mohammed
Atteia
1
Associate Professor of Endodontics, Department of Endodontics, Faculty of Oral and Dental Medicine, Cairo University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF DENTURE ADHESIVES ON SURFACE ROUGHNESS OF DENTURE BASE MATERIALS AND ITS RELATION TO CANDIDA ALBICANS ADHESION
Objectives: Candida-associated denture stomatitis is the most prevalent form of oral candidiasis affecting 65% of denture wearers. Continuous use of denture adhesives may affect the surface roughness of the denture material and may contribute to Candida adhesion. This study aimed to investigate surface roughness of two chemically different denture materials after exposure to denture adhesives and its relation to in vitro adhesion of Candida albicans.Materials and Methods: Five groups of both PMMA and UDMA specimens (10 mm 10 mm 2 mm) were prepared (10 specimens in each group). Specimens were immersed in Corega Cream (group 1), Corega Powder (group 2), Olivafix cream (group 3), Protefix cream (group 4) and distilled water (group 5). Specimens were tested for surface roughness, and in vitro Candida albicans adhesion.Results: The results showed that Corega cream had statistically significant effect on surface roughness of both types of resins (P < 0.05). On the other hand the other three types of denture adhesive and distilled water had no statistically significant effect on surface roughness (P > 0.05).The differences in the Candida count between the UDMA specimens were not statistically significant. On the other hand the Candida count of Corega cream exposed group was statistically significant if compared with other groups in the PMMA resin specimens. The differences in the Candida count between the specimens of both resin groups were statistically non-significant (P > 0.05)Conclusions: Exposure to Corega cream denture adhesives may induce changes in surface roughness of denture base materials. Candida albicans adhesion is not necessarily increased on denture base materials that are exposed to denture adhesives.
https://edj.journals.ekb.eg/article_76266_3286a9f9b1924f96d9ecb4035ee1599b.pdf
2017-10-01
3473
3481
10.21608/edj.2017.76266
denture base
denture adhesives
Candida albicans
Mahmoud
Mohamed
1
Lecturer of Removable Prosthodontics, Faculty of Dentistry, Suez Canal University, Ismailia, Egypt.
AUTHOR
Said
Daboor
2
Microbiology- National Institution of Oceanography and Fisheries, Cairo- Egypt.
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF ORAL HYGIENE IN PROGNOSIS OF DENTAL PROSTHESIS OF PATIENTS IN PROSTHODONTICS CLINIC
Interventions for better oral hygiene would be more successful if the patient with dental prosthesis knows more about his oral hygiene and how to maintain it.To assess the association between oral hygiene and its effect in the prognosis of patient with dental prosthesis or any dental restoration.The sample was composed by 240 cases divided in four provinces (Hadramoot, Aden, Laheeg and Taiz), 60 cases for each province were clinically examined..
https://edj.journals.ekb.eg/article_76267_b35065d40f8f7cda6b667fbffa247dae.pdf
2017-10-01
3483
3496
10.21608/edj.2017.76267
oral hygiene
diabetes
dental prosthesis
Nadra
Ishaq
1
Associated Professor & Chairman of Prosthodontic Department, Faculty of Dentistry, Aden University
AUTHOR
Mohammed
lsakkaf
2
Assistant Professor in Conservative Department & Dean of Faculty of Dentistry, Aden University
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF RETENTION OF TOOTH-COLORED VERSUS CAST METAL DENTAL CLASPS FOR A MANDIBULAR DISTAL EXTENSION PROSTHESIS
The aim of this study was to compare the retention of two different forms of clasps in mandibular distal extension prosthesis, which were; the Conventional casted metal clasps & the Tooth-colored acrylic resin clasps “Acetal resin”.Materials & Methods: For the rationale of this clinical investigation, fifteen patients were selected from the Outpatient Clinic of the Prosthodontic Department, Faculty of Oral and Dental medicine, Cairo University in accordance with certain criteria. Every patient got a skeleton parial denture that was constructed in a conventional manner. A hole was made in the middle of the lingual plate during fabrication of the framework; A Retention Measuring-Aided Device was made to allow attachment of the digital Forcemeter to this hole for measuring retention. Then, the metal clasp was removed and replaced by acetal resin clasp and the same procedures of measuring retention were performed in the same manner. Retention of the two clasp types was measured four times (at time of insertion, one month, two months and three months, respectively), by the aid of a prefabricated device (The Retention Measuring-Aided Device) for precise reproducible measurement.Results: There was a statistically significant difference (P ≤ 0.05) in the mean Forcemeter measurements from base line to one month. Later, from one month to 2 months and from 2 months to 3 months; there was a statistically insignificant difference (P ≥ 0.05) in the mean Forcemeter measurements. Conclusions and recommendations: Using Tooth-colored dental clasps would not compromise the retention of removable partial denture and can help to enhance the esthetics of removable partial dentures.
https://edj.journals.ekb.eg/article_76268_6ab9d2377c68f05041984111afaad6c7.pdf
2017-10-01
3497
3505
10.21608/edj.2017.76268
Acetal Resin
Cobalt-chromium
Forcemeter
retention
Esthetic clasps
Mostafa
Mostafa
1
Lecturer of Removable Prosthodontics, Faculty of Dentistry, Cairo University
AUTHOR
ORIGINAL_ARTICLE
COMPARISON BETWEEN LOCATER AND MAGNETIC ATTACHMENT SYSTEMS FOR SINGLE IMPLANT RETAINED MANDIBULAR OVERDENTURE (STRAIN GAUGE ANALYSIS)
Objective: the aim of this study was to compare stresses induced in locater and magnetic dome type attachments for single implant retained mandibular overdenture by using strain gauge analysis.Material and methods: One clear acrylic model was constructed representing completely edentulous lower ridge. A single implant was placed in the midline region of this model and two identical experimental overdentures were constructed. The first overdenture was fitted to single implant through a locater attachment while the second was fitted to implant through a Magnet Dome attachment. Four strain gauges were installed in labial and lingual surfaces and the right &left sides of single midline implant. A special loading device (universal testing machine) was used to apply standardized static vertical load with a magnitude of 100 N at the right first molar tooth on the occlusal surface of each experimental overdenture.Results: Comparing the two attachments that were studied, the differences were statistically significant, independent T test showed significant difference between Locater and Magnetic attachment groups. Conclusions: Within the limitation of this study, it could be concluded that: magnetic attachment induce less stresses than locater attachment in case of single implant retained mandibular overdenture.
https://edj.journals.ekb.eg/article_76269_d5d866f1442c0ae5804a7b9f59637031.pdf
2017-10-01
3507
3517
10.21608/edj.2017.76269
Hebatallah
Abdallah
1
Lecturer of Prosthodontics, Faculty of Dentistry. Ain Shams University
AUTHOR
Hanan
Al-Asad
2
Lecturer of Prosthodontics, Faculty of Dentistry, Aden University.
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF THE RETENTION IN THE THERMOPLASTIC ACETAL RESIN DISTAL EXTENSION PARTIAL DENTURE PROSTHESIS WITH DIFFERENT DENTURE BASE EXTENSIONS
Objectives: The present study was conducted to investigate the retention and the patient satisfaction of the Thermoplastic Acetal resin distal extension partial denture prosthesis with different denture base extension length either extended to covered the retro molar pad or extended just at the anterior border of the retro molar pad in unmodified Kennedy class II mandibular cases. Thermoplastic Acetal resin partial denture is more comfortable and can replace any number of teeth in a dental arch.Methods: Total number of ten healthy patients with unmodified Kennedy class II mandibular cases were selected and received extra coronal attachment on the experimental side , and received unilateral partial denture with thermoplastic Acetal resin framework. The patients were grouped into two groups. Group I received mandibular unilateral distal(without denture base extension) just end at the anterior border of the retro molar padand group II received mandibular unilateral distal(with denture base extension ) covered the retromolar pad. Then the retention evaluation and patient satisfaction was done at insertion of dentures , six months and after 12 month from the insertion.Results: For both groups regarding the retention evaluation, there was insignificant difference between both groups as P-value > 0.05. Regarding the patient satisfaction Group I (without denture base extension) showed statistically significantly higher mean satisfaction score than Group II.Conclusions: The patients were received mandibular unilateral distal(without denture base extension) more satisfied by the prosthesis. and regarding the retention there was non significant difference between both groups so theunilateral partial denture with thermoplastic Acetal resin framework without denture base extension more preferable .
https://edj.journals.ekb.eg/article_76271_fdebb5d8023b1d131357e48a5173cde3.pdf
2017-10-01
3519
3526
10.21608/edj.2017.76271
Distal extension Removable partial denture
AThermoplasticAcetal resin framework
Mai
Helmy
1
Lecture , Prosthodontic Department, faculty of dentistry , Cairo university.
AUTHOR
ORIGINAL_ARTICLE
SHEAR BOND STRENGTH OF UNIVERSAL-ADHESIVE TO DIFFERENT FIXED PROSTHODONTIC MATERIALS
Objectives: To evaluate the shear bond strength (SBS) of Universal adhesive (Single Bond Universal SBU), that contain silane and MDP adhesive molecules, to different fixed prosthodontic materials (High-Leucite ceramics, Zirconia ceramics and base metal alloys).Methods: Twenty high-leucite based ceramics IPS Empress (Ivoclar) and twenty Ni-cr alloys Remanium-CSe(Dentaurum) specimens were constructed in discs of 5mm diameter and 3mm thickness. Twenty Zirconia based ceramics INcoris-TZI (Sirona) specimens were prepared of 19X15X3mm blocks. All specimens were embedded into acrylic resin blocks of 2x2X2cm. Composite discs 3mm in diameter Z-350(3M ESPE) were prepared and bonded to each material, divided into 2 groups according to the bonding procedures (N=10). High-Leucite ceramics etched with 5%HF acid then for Group1 composite discs were bonded with Single Bond2 SB2 and RelyX ultimate resin-cement RXU, after Silane Si application (Si+SB2+RXU), for Group 2 composite discs were bonded with Single Bond Universal adhesive and RelyX Ultimate without separate Silane application (SBU+RXU). Metal and zirconia specimens were air abraded 50µm AL2O3 then for Group 1; composite discs were bonded with Panavia cement only (Pa). For Group 2, composite discs were bonded with Single Bond Universal and RelyX Ultimate (SBU+RXU). All the specimens were thermo-cycled in water baths 5-55°C for 5000 cycles. The SBS was tested in a universal testing machine (Tira) using a chisel-edge blade. The results were statistically analyzed using Mann-Whitney test.Results: bThe mean (SBS±SD) in MPa were: In high leucite ceramics (23.1±2.5), (23.6± 1.9) for (Si+SB2+RUX) and (SBU+RUX) respectively. In Zirconia ceramics: (7.96± 3.1) and (16.8± 5.4) for (Pa) and (SBU+RXU) respectively. In Base metal alloys: (14.8±5.4) and (20.9±2.7) for (Pa) and (SBU+ RXU) respectively. Statistical analysis using Mann-Whitney test showed no significant difference for the high leucite and base metal groups (P>0.05) while there was significant difference for the zirconia groups (P<0.05). Conclusion: The Universal-adhesive SBU produced bond strength to high leucite-ceramics comparable to that of resin cement with separate Silane application. It produced higher bond strength to zirconia ceramics and base metal alloys in comparison to Panavia adhesive-resin cement.
https://edj.journals.ekb.eg/article_76272_a1ecc6c554d59ca8fe097988bfc5d6d8.pdf
2017-10-01
3527
3534
10.21608/edj.2017.76272
Universal adhesive
Shear bond strength
zirconia-ceramics
leucite-ceramics
base metal alloy
Diaaeldin
Awad
1
Lecturer of crown & bridge, Department of crown & bridge, Faculty of Dentistry, Suez Canal University. Ismailia, Egypt
AUTHOR
ORIGINAL_ARTICLE
SHEAR BOND STRENGTH OF DIFFERENT ADHESIVE RESIN CEMENTS TO DENTIN
Objective: This study investigated the shear bond strength SBS of different adhesive resin cements [self-adhesive resin cement RelyX Unicem(RXU), adhesive resin cement with self-etch adhesive RelyX Ultimate with Single bond Universal adhesive (RXUT) and adhesive resin cement that utilize etch and rinse technique RelyX ARC with Single bond2 adhesive (ARC)] to dentin. Methods: Sixty extracted molars embedded in epoxy resin were prepared by sectioning the buccal surface to expose flat Buccal dentin and were ground with 400-grit SiC paper. The samples were divided into 3 groups (N=20) based on the adhesive resin cements used. Sixty composite discs 3mm in diameter Z 350 (3M ESPE)) were constructed & bonded to the prepared dentin surfaces according to manufacturer instructions. For each group half the samples were thermo-cycled (TC) between 5-55˚C for 2500 cycles and then all samples were tested using a universal testing machine using chisel blade. The results were statistically analyzed using Mann-Whitney &Wilcoxon Signed Ranks tests.Results: The mean SBS (± standard deviation) were: 6.95±1.5 MPa for RXU, 0 for RXU(TC), 22.58±5.45 for RXUT, 15.20±3.98 for RXUT (TC), 25.9±5.3 for ARC, and 19.5±4.3 for ARC(TC). RXU had significant lower bond strength than both RXUT &ARC (P<0.05). No significant difference between RXUT & ARC after thermo-cycling (P>0.05).Conclusions: (1) The self-adhesive resin cement (RXU) had significant lower bond strength to dentin than that of RXUT & ARC. (2) No significant difference was found between the used adhesive resin cements that utilized self-etch adhesive and that utilized etch & rinse adhesive.
https://edj.journals.ekb.eg/article_76274_b29ed59214a261c873500fd695505af3.pdf
2017-10-01
3535
3543
10.21608/edj.2017.76274
Diaaeldin
Awad
1
Lecturer of Crown & Bridge, Department of Fixed Prosthodontics, Faculty of Dentistry, Suez Canal UniversityIsmailia, Egypt
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF THE PROPERTIES OF A NOVEL HYBRID ELASTOMERIC IMPRESSION MATERIAL
The aim of this study was to evaluate and compare the flow of a polyether, and poly vinylsiloxane impression materials with a recently introduced vinyl polyethersilicone hybrid elastomeric impression material.Materials and methods: The flow of the medium viscosities of the tested materials was measured using the shark fin Device. One minute after the start of mixing, the pin was released and the solid cylinder was allowed to sink into the impression under its own weight, where the material flowed up into the slit producing a shark fin-like layer of tested impression material. The heights of the shark fin were measured at 60 minutes after the start of mixing, using a digital micrometer with 0.001 mm resolution. One-way Analysis of Variance (ANOVA) was used for comparison between the three groups. Tukey’s post-hoc test was used for pair-wise comparison between the groups when ANOVA test is significant.Results: there was a statistically significant difference between fin heights of the three materials (P-value <0.001), where polyether showed the statistically significantly highest mean fin height (12.7), however the hybrid material showed statistically significantly lower mean fin height (7.6). Moreover addition silicone showed the statistically significantly lowest mean fin height (5.5).Conclusion: Hybridization of addition silicon and polyether impression materials improved their flow.
https://edj.journals.ekb.eg/article_76276_6386f956651992a92d350ab2047f961b.pdf
2017-10-01
3545
3549
10.21608/edj.2017.76276
Flow
vinylsiloxnether
shark fin test
Heba
Shalaby
hebashalaby62@gmail.com
1
Professor Restorative Dentistry Department, Faculty of Dentistry, King Abdul Aziz University, Jeddah, KSA.
AUTHOR
ORIGINAL_ARTICLE
COMPARATIVE EVALUATION OF SMEAR LAYER REMOVAL, CALCIUM IONS LOSS AND DENTIN MICROHARDNESS AFTER DIFFERENT FINAL IRRIGATION SOLUTIONS
Aim: The aim of this study was to evaluate the smear layer removal ability of three different irrigation solutions and their effect on calcium ion loss and dentin microhardness.Materials and Methods: Forty root samples were used in this study. Samples were divided into four groups according to the type of irrigant used as a final rinse into: group A; 5.25% Sodium hypochlorite (NaOCl) (control), group B; 17% Ethylenediamine tetraacetic acid (EDTA), group C; QMix 2in1, and group D; 0.2% Chitosan. After final rinse the measurement of Ca ions loss was done using atomic absorption spectrophotometry. Then, samples were divided longitudinally into two halves. One half of each sample was evaluated for smear layer removal ability using Environmental Scanning Electron Microscope. The other half was examined for dentin microhardness using Vickers microhardness tester. Parametric data were analyzed by One Way ANOVA test then, Games-howell test and Tukey post-hoc test and none parametric data were analyzed by Kruskal-Wallis and Dunn’s test at P ≤ 0.05. Results: NaOCl did not show any smear layer removal ability, while EDTA, QMix, and Chitosan showed complete smear layer removal and patent dentinal tubules particularly at the cervical third. EDTA, QMix, and Chitosan recorded the highest Ca ion loss and the lowest microhardness than NaOCl. Conclusion: EDTA, QMix, and Chitosan significantly removed smear layer and so released higher amount of Ca ion which adversely affect the microhardness. It remained difficult to completely remove smear layer from the apical third and so it recorded the highest microhardness.
https://edj.journals.ekb.eg/article_76277_92488c0c01f040fbbfcdfd01d5a674f0.pdf
2017-10-01
3551
3562
10.21608/edj.2017.76277
Chitosan
EDTA
QMix
Ca ion loss
Microhardness
Smear layer
Reem
Abd-Elgawad
1
Lecturer in Endodontics, Faculty of Dentistry, Suez Canal University
AUTHOR
Dalia
Fayyad
2
Associate professor of Endodontics, Faculty of Dentistry, Suez Canal University.
AUTHOR
ORIGINAL_ARTICLE
DO ESTHETICS CONTRADICT WITH FUNCTION? IN VITRO ASSESSMENT OF LOAD DEFLECTION AND FRICTIONAL RESISTANCE OF COATED VERSUS UNCOATED SUPERELASTIC NICKEL-TITANIUM ARCHWIRES
Objectives: The present study aimed to investigate the effect of esthetic coating on the load deflection properties, surface roughness and frictional resistance of superelastic Ni-Ti orthodontic wires. Materials and Methods: Four types of Ni-Ti wires were investigated: Alpha Wire Super Elastic Ni-Ti, OrthoPro (Uncoated OP) and its coated counterpart: Alpha Wire Tooth-Coated Super Elastic Ni-Ti, OrthoPro (Coated OP); Super-elastic Nitanium, Ortho Organizer (Uncoated OO) and its coated counterpart: Super-elastic Nitanium Tooth Tone, Orthodontic Organizer (Coated OO). The load deflection properties were investigated using three-point elastic bending test by a universal testing machine (Lloyd Instrument LR5K series, London, UK) to record the average unloading force (n=8). The surface roughness was measured using a non-contact profilometer (ZYGO Maxim-GP 200, USA) (n=4). The static and dynamic frictional resistances were measured using a specially designed test assembly that allows sliding the wires through the slots of monocrystalline zirconia brackets using a universal testing machine (n=8). Results: No significant difference was found between the coated OP wires and their uncoated controls regarding the load deflection, surface roughness or frictional resistance whether static or dynamic. On the contrary, compared to their uncoated group, the coated OO wires showed significantly lower average unloading force, higher surface roughness, and higher static and dynamic friction. Conclusions: The effects of the esthetic coating on the critical function-related properties of orthodontic wires vary from one manufacturer to another which indicates that satisfying the esthetic demand does not always come at the expense of wire function.
https://edj.journals.ekb.eg/article_76465_d1ba8508f85137d7f7a101455e0ab1e7.pdf
2017-10-01
3563
3573
10.21608/edj.2017.76465
Esthetic
coated
superelastic
Nickel-titanium
load-deflection
Surface roughness
frictional resistance
static friction
dynamic friction
Gihan
Waly
1
Assistant Professor, Biomaterials Department, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
ORIGINAL_ARTICLE
COMPARISON OF PERI-IMPLANT CLINICAL INFLAMMATORY PARAMETERS AMONG SCREW RETAINED CAD/CAM METAL BAR AND ZIRCONIA BAR FOR PATIENTS WITH RECONSTRUCTED MANDIBLES
Background: Segmental resection of the mandible results in severe disturbance of chewing function. Advances in microvascular surgeries and CAD/CAM technology helped with the prosthetic rehabilitation of reconstructed mandibles.Purpose: The aim of this study was to assess metal bar versus zirconia bar in patients with reconstructed mandibles that were rehabilitated with implant retained mandibular removable partial overdenture concerning the peri implant gingival index and probing depth.Materials and methods: fourteen patients were selected according to the inclusion criteria, the participants were stratified equally into two groups, patients were assigned to receive either metal bar or zirconium bar. Preparation of implant sites started with pilot drill followed by sequential drilling under copious refrigerated irrigation. Monthly follow up appointments were scheduled for each patient. After second stage surgery, abutments were secured to implant fixtures. Open top impression technique was used for bar fabrication using CAD/CAM technology. The bar was screwed in the patient’s mouth and checked for passive fit. Construction of the implant assisted removable partial overdenture took place in the conventional way. Female part were picked up directly in the patient’s mouth. Patients were recalled one week, 3,9 and 12 months after delivery for assessment of gingival index and probing depth. Results: Mann-Whitney U test was used to analyze the gingival index score between the two groups metal bar and zirconium bar. The metal bar group mean and standard deviation was 0.40±0.48 after 1 week and 0.36±0.32 after 3 months, 0.30±0.42 after 9 months, 0.20±0.42 after 12 months. While for zirconium group 0.30 ± 0.70, 0.28± 0.42 ,0.25±0.32, 0.10±0.32 respectively after 1 week,3 months ,9 months and 12 months. There was a statistical significance between the groups in 9 and 12 months, where P value was Conclusion: Within the limitation of this study, zirconia metal bar is considered more biocompatible than the metal bar.
https://edj.journals.ekb.eg/article_76278_8d97bf199354cde41998e3fa9ee0baff.pdf
2017-10-01
3575
3583
10.21608/edj.2017.76278
Reconstructed mandibles
splinted implant screw retained bar
Zirconia
CAD/CAM
Mahmoud
El Homossany
1
Lecturer Removable Prosthodontics Department, Faculty of Dentistry, Ain Shams University.
AUTHOR
Hebatallah
Abdallah
2
Lecturer Removable Prosthodontics Department, Faculty of Dentistry, Ain Shams University.
AUTHOR
ORIGINAL_ARTICLE
PENETRATION OF AMALGAM CORRODED PRODUCTS INTO DENTIN AND ITS EFFECT ON BONDING USING SELF ETCH ADHESIVE SYSTEM VERSUS RESIN MODIFIED GLASS IONOMER
Introduction: amalgam replacement by tooth-colored restorations has become a common procedure nowadays. Aim: this study was carried out to detect the effect of Penetration of amalgam corroded products into dentin on bonding of both self etch adhesives and resin modified glass ionomer (RMGI). Materials & method: 40 simple occlusal cavities were made in human extracted molars. Cavities were filled with amalgam, stored for one year then amalgam was removed and teeth were divided into two main groups (20 teeth each); group A; where amalgam was without any further increase in cavity depth. Group B; where amalgam was totally removed followed by further increase in cavity depth by 0.5 mm. each group was re divided according to the restorative material used to replace amalgam where group 1: resin composite with self etch adhesive, group 2: RMGI. Teeth were sliced and the interface was examined by scanning electron microscope coupled with EDAX. Results: amalgam remnants appeared at the interface of group A to interfere with bonding while it disappeared from the interface at group B. conclusion: increasing depth of the cavity by 0.5 mm after amalgam removal showed a more reliable interface for the subsequent tooth colored restoration.
https://edj.journals.ekb.eg/article_76422_d991530160486a17230f3108551812dc.pdf
2017-10-01
3585
3591
10.21608/edj.2017.76422
Ali
Abdelnabi
1
Researcher at Operative, Endodontics and Dental Materials Department, National Research Center.
AUTHOR
Nermeen
Hamza
2
Lecturer of Operative Dentistry, MSA University
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF THE SURFACE ROUGHNESS OF THREE ESTHETIC DENTURE BASE MATERIALS
Aim: This study was conducted to compare the surface roughness of three denture base materials. Materials and methods: Three materials were selected for the study; conventional heat cured polymethyl methacrylate resin (PMMA), Acetal resin and Polyetherether ketone (PEEK). Seven specimens of each material were constructed in the form of a disc 1cm in diameter and 1.5 thickness. Each disc had one finished surface and one polished surface. Surface roughness for both surfaces was measured for all specimens, then the discs were immersed in artificial saliva for 24 hours, one week and one month and surface roughness was measured at each interval. Two way ANOVA test was used for the statistical analysis.Results: PMMA showed the highest mean surface roughness at the base line stage i.e. before insertion in saliva. Also PMMA showed the highest mean surface roughness compared to the other two materials through the follow up period however the increase was statistically insignificant.p=0.814.After insertion in saliva PMMA showed statistically significant increase in the mean surface roughness p<0.0001.Conclusion: The study showed that Acetal resin base material and poly-ether-ether ketone showed significantlylower surface roughness than PMMA.
https://edj.journals.ekb.eg/article_76423_507ce5c01245fdd102f8e43b23702968.pdf
2017-10-01
3593
3599
10.21608/edj.2017.76423
Surface roughness
Denture base materials
Acetal Resin
PEEK
Nancy
Elsherbini
1
Lecturer of Removable prosthodontics, Faculty of Oral and Dental medicine, Cairo University
AUTHOR
ORIGINAL_ARTICLE
CALCIUM ENRICHED MIXTURE USED FOR PERMANENT MOLAR PULPOTOMY IN TEETH DIAGNOSED AS IRREVERSIBLE PULPITIS: A CASE SERIES
Aim: To evaluate the clinical and radiographic pulpotomy outcomes in permanent molars diagnosed as irreversible pulpitis using Calcium Enriched Mixture (CEM) as the pulpotomy material. Materials and Methods: Eight patients with 8 permanent molars demonstrating signs and symptoms of symptomatic / asymptomatic irreversible pulpitis were included. For all patients, after rubber dam application, standardized pulpotomy was performed. Sodium hypochlorite 5 % was used to obtain haemostasis. A mixture of CEM was placed in the pulp chamber. Molars were restored with a glass ionomer restoration. After seven days, the glass ionomer restoration was covered by stainless steel crowns. Recall assessment was appointed at 3, 6, 12 months. Results: Patients’ age at the time of treatment was at range from 9.10 to 15 years. Most of the molars (75%) were having symptomatic irreversible pulpitis, with 88% demonstrating symptomatic apical periodontitis. To stop pulpal hemorrhage time range was between 1-12 minutes (mean 4.8 ± 4.5 minutes). The follow-up examination period ranged from 15- 17 months with a mean of 16.6 ± 0.5 months. At the beginning of the study 3 molars that had open apices (38%) all of them showed continued root maturation. Four molars that showed radiographic apical radiolucencies (50%), all lesions healed completely by the end of the follow-up period. One case (13%) showed partial with no complete root canal obliteration. There were neither periradicular bone nor root resorption. Additionally, no evidence of internal root resorption was noticed. Conclusion: Successful outcomes of this case series recommend the use of CEM as a simple, useful and applicable pulpotomy agent in the treatment of permanent molars having irreversible pulpitis. However, more studies are needed to assess this procedure including larger number of patients over longer period of recalls.
https://edj.journals.ekb.eg/article_76424_c52530c094e644c61ff1c2cc021e8b42.pdf
2017-10-01
3601
3609
10.21608/edj.2017.76424
CEM
Irreversible pulpitis
Molar
Pulpotomy
Marwa
Sharaan
1
Lecturer in Endodontics, College of Dentistry, Suez Canal University
AUTHOR
Asmaa
Abo Elsoud
2
Lecturer in Department of Pediatric and Preventive Dentistry and Dental Public Health, College of Dentistry , Suez Canal University
AUTHOR
ORIGINAL_ARTICLE
SHEAR BOND STRENGTH AND INTERFACIAL MICROSCOPIC EXAMINATION OF TWO TYPES OF FLOWABLE RESIN-COMPOSITE TO ENAMEL SURFACE OF DECIDUOUS MOLARS
Aim: Evaluation of shear bond strength of a self-adhering flowable resin-composite versus total-etch one to enamel surface of deciduous molars. Interfaces between these restorations and primary enamel were also microscopically investigated. Materials and Methods: Twenty freshly extracted human deciduous molars were used. For the shear bond strength, twelve molars were embedded in acrylic blocks, such that their buccal surfaces were aligned with the acrylic. The enamel surfaces were subjected to minimal grinding. The teeth were randomly divided into two groups, Group I: Self-adhering flowable resin-composite (Dyad™-flow, Kerr, USA); Group II: Total-etch flowable resin-composite necessitate etching and bonding (Filtek™Z350-XT, 3M-ESPE, USA). A specially designed holed-split Teflon mold was used for constructing resin-composite cylinders (3x3mm) over the buccal surfaces of the mounted teeth. For group I, resin-composite was applied directly on teeth surfaces using the mold and light-cured for 20seconds. For group II, using the mold the following steps were performed: acid etching (15 seconds), 2) bonding agent (light-curing 20 seconds) and 3) resin-composite (light-curing 20 seconds). The teeth were stored in 37°C distillate water for 24 hours. The shear bond strength was recorded and statistically analyzed. Modes of failure were studied using digital microscope. For interfacial examination, cavities (class V) were prepared in buccal surface of eight teeth, filled by the two flowable composites as previous (n=4/group) and scanned using scanning electron microscope. For each group, two teeth were examined from buccal aspect, while the other two were sectioned and inspected.Results: Mean bond strength values for groups I and II were 5 and 21.6 MPa respectively with highly significant difference P=0.005 (P value ≤ 0.01). Modes of failure for groups I and II were [100%adhesive] and [16.7%cohesive within tooth + 83.33%mixed] respectively. SEM micrographs of group I revealed a gap at enamel-restoration interface, while group II showed cohesive failure within enamel at the margins. Conclusions: The bonding performance of the self-adhering resin-composite “Dyad™-flow” still needs further enhancement. Modifications may be required to prevent marginal enamel cracks with the use of Total-etch “Filtek™Z350-XT” flowable resin-composite.
https://edj.journals.ekb.eg/article_76425_5539ba3533e268303179a979abce48ce.pdf
2017-10-01
3611
3616
10.21608/edj.2017.76425
Rasha
Abdelraouf
1
Department of Biomaterials, Faculty of Oral and Dental Medicine, Cairo University, Egypt
AUTHOR
Manar
Mohammed
2
Department of Pediatric and Community Dentistry, Faculty of Oral and Dental Medicine, October 6 University, Egypt
AUTHOR
Fatma
Abdel Gawad
3
Department of Pediatric Dentistry and Dental Public Health, Faculty of Oral and Dental Medicine, Cairo University, Egypt
AUTHOR
ORIGINAL_ARTICLE
FRACTURE RESISTANCE OF DIFFERENT ESTHETIC POST AND CORE MATERIALS AND ASSESSMENT THEIR MODE OF FAILURE
Purpose: This in vitro study measured fracture resistance of different esthetic post and core materials and compare their modes of failures. Statement of problem: Increase esthetic demand and patient awareness have encouraged development of esthetic post and core systems. Translucency of ceramic restorations is accompanied by marked decrease in alumina content that may affect mechanical properties. Methods:40 extracted human central incisors were used in this study. Teeth were randomly divided into 4 groups of 10 each: group 1:Translucent Zirconia(TZ);group 2:High Translucency IPS E.Max (T-IPS); group 3:Polymer Infiltrated Ceramic (Vita Enamic) (PIC) and group 4: Control group (C), teeth were endodontically treated with no posts and cores. Posts and cores were processed according to manufacturer instructions cemented to teeth with adhesive resin cement; then specimens were mounted to acrylic resin blocks, attached to Instron universal testing machine, and loaded with a crosshead speed of 0.5 mm/min, until fracture. Types of failures were also recorded in different groups. Data were statistically analyzed using 1-way analysis of variance (ANOVA), and Scheffe test made pairwise comparison (α = 0.05). Results: TZ group showed the highest fracture resistance (454 .4±41.6 N). T-IPS showed higher results(360.4±35.7N) than PIC(300.9±35.6 N) and control(276.7±32.5 N) and the two latter groups were not significantly different from each other P Conclusions: Regarding fracture strength and mode of failure, High Translucent IPS-E Max post and core can be an alternative treatment method when compared with other techniques.
https://edj.journals.ekb.eg/article_76426_d38026264e792c0440879b89492527ee.pdf
2017-10-01
3617
3624
10.21608/edj.2017.76426
Ahmed
Hamdy
1
Associate Professor, Fixed Prosthodontics Department, Faculty of Oral and Dentistry, Modern Science and Arts University.
AUTHOR
ORIGINAL_ARTICLE
CURING EFFECTIVENESS OF NANOFILLED RESIN COMPOSITE USING DIFFERENT LED CURING INTENSITIES AT DIFFERENT IRRADIATION TIME
Aim: evaluated the effectiveness of different LED curing light intensities at different irradiation time on the microhardness and depth of cure (hardness ratio) of nanofilled resin composite material.Materials and methods: Nanofilled resin composite material (Filtex Z350XT, 3M, ESPE) and LED curing unit (Dr’s light AT, Good doctors co.ltd. korea) with two different light intensities were used in this study. Two Circular Teflon moulds with two different thickness were used to prepare 25Resin composite discs specimen that were divided into five groups (5 discs each). For group 1, 2mm thick resin composite disc specimens where polymerized using standard light curing intensity (800 mW/cm2) for 30 sec. while for group 2, 4mm thick resin composite disc specimens where polymerized using standard light curing intensity (800 mW/cm2) for 30 sec. group 3, 2mm thick resin composite disc specimens where polymerized using high intensity light curing mode (1400 mW/cm2) for 10 sec. group 4, 4mm thick resin composite disc specimens where polymerized using high intensity light curing mode (1400 mW/cm2) for 10 sec. Group 5, 4mm thick resin composite disc specimens where polymerized using high intensity light curing mode (1400 mW/cm2) for 20 sec. Microhardness testing was performed and the mean microhardness values and hardness ratio % of the specimens were calculated, tabulated and statistically analyzed using independent (unpaired) t test for 2 groups comparisons while one way analysis of variance (ANOVA) and Tukey post hoc tests were used to study the significance between more than 2 groups. The significance level was set at p ≤ 0.05. Statistical analysis was performed with SPSS 19.0 Results: The highest mean value was recorded in group 5: 4mm thick disc specimens cured with high intensity for 20 sec (91.16%), whereas the lowest mean was recorded in group 4: 4mm disc specimens cured with high intensity for 10 sec (73.34%). A significant difference was found between both groups (p=0.032). However, no significant difference was detected between group 3: High 10 (2mm) that recorded 85.56% , group 5: High 20 (4mm) recording 91.16% and group 1 and 2: standard ( 2mm and 4mm respectively) recording 86.96% and 81.08% respectively.Conclusions: 1. Depth of cure and microhardness values were greatly affected by the interaction between curing light intensities and irradiation time and material thickness as well. 2. Nanofilled resin composites irradiated with LED high light intensity (1400 mW/cm2) for 20 sec. demonstrated a higher microhardness. 3. Composites might be cured in increments higher than 2 mm and up to 4mm when using LED high intensity light curing system with special caution to the irradiation time applied.
https://edj.journals.ekb.eg/article_76427_f67b23202f94901b0ae5704fdb4039d7.pdf
2017-10-01
3625
3631
10.21608/edj.2017.76427
nanofilled composite
depth of cure
LED
light intensities
microhardness ratio
Shereen
Hafez
1
Lecturer of Conservative Dentistry, Faculty of Dentistry, Cairo University
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF DIFFERENT LED CURING INTENSITIES ON COLOR STABILITY OF NANOFILLED RESIN COMPOSITE
Aim: to evaluate the effect of different LED curing intensities on color stability of nanofilled resin composite.Materials and methods: nanofilled Resin composite discs specimen (Filtex Z350XT, 3M, ESPE) were prepared and light cured with LED curing unit either standard intensity for 40 sec or high intensity for 20 sec. The specimens’ colors were measured (as a base line) using a portable Reflective spectrophotometer (X-Rite, model RM200QC, Neu-Isenburg, Germany) and measurements were made according to the CIE L*a*b* color space relative to the CIE standard illuminant D65. specimens of each group were immersed for one day in tea solution. After immersion the color changes (ΔE) of the specimens were evaluated. Statistical analysis was then performed. As data was parametric, significance of the difference between groups was evaluated using unpaired t test. The level of significance was set at P < 0.05.Results: A higher mean value was recorded with high intensity light curing. Unpaired t test revealed that the difference was statistically significant (p=0.0442).Conclusions: the different light curing intensities might affect the color stability of nanofilled resin composite. The effect of beverages as staining solutions on color stability of resin composite restoration might be immersion-time and resin material dependent. Nanofilled resin composite with optimum polymerization might show more color stability.
https://edj.journals.ekb.eg/article_76428_62a00cfe1e5a581af9fd7a21b7316f0d.pdf
2017-10-01
3633
3638
10.21608/edj.2017.76428
LED light intensity
nanofilled composite
color stability
Shereen
Hafez
1
Lecturer of Conservative Dentistry, Faculty of Dentistry, Cairo University
AUTHOR
Rasha
Raafat
2
Lecturer of Conservative Dentistry, Faculty of Dentistry, Cairo University
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF MICROBIAL ADHESIONS AND QUALITY OF LIFE IN MAXILLECTOMY PATIENTS REHABILITATED WITH COBALT-CHROMIUM AND THERMOPLASTIC OBTURATORS
Objective: The purpose of the this study was to evaluate the oral microbial adhesions and quality of life in Maxillectomy patients after rehabilitation with two types of maxillofacial obturators: Thermopress & Cobalt- Chromium obturators.Materials and Methods: Type of study: Randomized clinical trial (RCT) Ten hemi-maxillectomy patients were taken from the out-patient clinic of the national Institute. Patients Grouping: Patients were randomly divided into two equal groups. Group-I: Five patients had received thermopress obturators. Group–II: patients were rehabilitated with cobalt chromium & polymethyl methacrylate obturators. - Microbial adhesions of viable microorganisms in the accumulating biofilm layer on Polymethylmethacrylate (PMMA) & Thermopress obturator bulb surfaces were determined along four weeks period & converted to Colonies Forming Units (CFU) per cm2 unit surface area . -QOL was evaluated according to the Obturator Functioning Scale’ (OFS). questionnaire by direct interviews with the patients at the end of four weeks period.Results: The results of this study revealed that the microbial adhesions showed statistically significant increase in Group-I patients compared to Group-II; On the other hand, the patient’s quality of life in Group-I recorded higher values in the examined domains than Group- II patients.Conclusion: Within the limitations of this study; it may be concluded that: Thermopress material may induce more microbial adhesions than Cobalt chromium &PMMA ones. Thermoplastic obturators may provide maxillectomy patients better esthetics, speech & social interaction than metalic obturators with conventional PMMA.
https://edj.journals.ekb.eg/article_76429_c309021c8e3b900a147acf9466e597dc.pdf
2017-10-01
3639
3650
10.21608/edj.2017.76429
Obturators
Therompress
PMMA
microbial adhesion
QOL
Azza
Metwaly
1
Associate Professor, Department of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University, Egypt
AUTHOR
Eatemad
Taha
2
Associate Professor, Department of Removable Prosthodontics, Faculty of dentistry, Ahram Candian University
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF TEA AND COFFEE ON THE COLOR STABILITY OF BULK AND INCREMENTAL FILL RESIN COMPOSITE
Objective: Two types of tea and coffee were selected to examine the color stability of bulk fill and incremental fill resin composite after storage for one and seven days. Materials and methods: A total of 150 resin composite discs (Filtek™ Z350), bulk fill (Xtra-fil) and (Filtek bulk) were prepared using a cylindrical mold (2x4). Ten specimens of each restorative material were left in distilled water for one day to be used for baseline color assessment. Then each tested material where either placed in black coffee, black tea, lemon ice tea or coffee milk beverages for one day or seven days inside an incubator at 36±1 °C. The relative spectral reflectance of each specimen was assessed using a spectrophotometer after storage in these beverages. Results: Kruskal-Wallis statistical test showed that there is a statistically significant difference between the three tested restorative materials after storage for one day and after 7 days in all the storage beverages where (p < 0.05). At the two aging periods, Z350 showed the statistically significant highest ΔE, X-tra fil showed the lowest statistically significant ΔE, while there was no statistically significant difference in the mean values of ΔE of Filtek bulk and these two materials. Regarding the effect of storage beverages on each restorative material at the two storage periods, black tea caused the highest statistically significant ΔE, while coffee milk caused the lowest statistically significant ΔE in the three tested resin composite.
https://edj.journals.ekb.eg/article_76431_1b6877492b672d6181fb1e3b105e0542.pdf
2017-10-01
3651
3665
10.21608/edj.2017.76431
color stability
Bulk Fill
Incremental fill
Coffee
tea
lemon tea
coffee milk
Spectrophotometer
storage time
Aliaa
El Wakeel
1
Lecturer of Conservative Dentistry MSA University, Faculty of Dentistry, Modern Science and Art University, Giza, Egypt
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF DIFFERENT SURFACE CONDITIONING METHODS ON THE BOND STRENGTH OF ZIRCONIA CERAMIC TO A RESIN CEMENT
Surface conditioning methods used for resin bonding to conventional silica base dental ceramics are not dependable for zirconium ceramic. The aim of this study was to evaluate the effect of different surface conditioning methods on the shear bond strength of zirconia ceramic to resin cement. Twenty eight Zirconia ceramic specimens were fabricated from (IPS e.max Zir CAD), and randomly assigned to four groups (n=7).Each group was subjected to the following surface treatments: Control (no treatment), sandblasting with 110 µm aluminum oxide, Silica coating and silanization (CoJet system), and Nd: YAG laser irradiation. A composite resin discs were fabricated and bonded to the treated ceramic surfaces using resin luting agent (Panavia F 2.0) and stored for 24 hours in distilled water at 37 OC. Specimens then subjected to thermocycling for 1000 cycles between 5O C and 55O C with a 30 s dwell time. All specimens were subjected to shear bond strength test by a universal testing machine at a crosshead speed of 0.5 mm/minute. The shear bond strength values were analyzed with ANOVA to compare between groups using SPSS software .The level of significance was 0.05. Results obtained showed that silica coating and silanization (CoJet system) is an effective method for achieving an acceptable bond between zirconia and resin cement. The use of Nd: YAG laser enhance the bond strength between the zirconia and resin cement.
https://edj.journals.ekb.eg/article_76432_8c24a55cc9aaef826edd1114079f8970.pdf
2017-10-01
3667
3672
10.21608/edj.2017.76432
Tarek
Abdelrehim
1
Associate Professor of Prosthodontics, King Abdul-Aziz University, Faculty of Dentistry, KSA
AUTHOR
ORIGINAL_ARTICLE
AN EVALUATION OF MAXILLARY MOLARS ROOT CANAL MORPHOLOGY USING CONE-BEAM COMPUTED TOMOGRAPHY IN AN EGYPTIAN SUBPOPULATION
Introduction: The aim of this study was to assess the root canal anatomy of maxillary permanent molars using cone beam computed tomography (CBCT), in an Egyptian Ismailia population. Methods: Four hundred and thirty two maxillary molars were included in this study. CBCT scans were evaluated by an oral radiologist and an endodontist. Root morphology and number as well as root canal number were evaluated. Root canal configurations were classified according to Vertucci’s method. Gender and bilateral symmetry were recorded. For root canal configurations, gender and bilateral sides, Pearson’s chi-square test was used (P ≤ 0.05). Results: The 216 maxillary first (1st ) molars that were included demonstrated only 3 roots configuration. On the other hand, 216 maxillary second (2nd ) molars displayed wide variety of root configuration. The most common was 3 followed by 2 and the least single root configuration . Regarding maxillary 1st molars, the highest frequency of Vertucci’s classification for the mesiobuccal root (MBR) were type II (82.4%), type IV (6.48%), type I (9.72%) and type III (1.39%). For the distobuccal root (DBR), the most common of Vertucci’s classification were type I (98.15%) and type II (1.85%). Regarding maxillary 2nd molars, the highest frequency of Vertucci’s classification for the MBR were type II ( 55.09%), type I ( 38.9%), type IV (3.70%) and type III (2.31%). For the DBR , the most common of Vertucci’s classification were type I (99%) and type II (0.01%). Incase of 2 roots, 1.4%, 1.9% had Type I for the buccal and palatal roots respectively. Additionally, type II was found in 0.5% of the cases. For one root, only one case (0.5%) was found had Type I. No anatomic variation was found for palatal roots for maxillary 1st and 2nd molars. Although, there was significant difference between females and males in most of the cases, the frequency of having 2nd canal in the MBR is comparable in both genders. There was no statistical difference between both sides. C-shaped canals were noticed in maxillary molars. Bilateral symmetry was displayed. Conclusion: Pre-assessment of the maxillary molars using CBCT imaging provides clear data for the root canal morphology that might increase the prognosis of the root canal treatment.
https://edj.journals.ekb.eg/article_76433_043faa710a2e893d9fd65897fb6dc90d.pdf
2017-10-01
3673
3681
10.21608/edj.2017.76433
Marwa
Sharaan
1
Lecturer in Endodontics, College of Dentistry, Suez Canal University.
AUTHOR
Ahmad
Elrawdy
2
Lecturer in Oral Radiology, College of Dentistry, Suez Canal University.
AUTHOR
ORIGINAL_ARTICLE
COMPARISON OF THE EFFECT OF CALCIUM HYDROXIDE AND THE MODIFIED TRIPLE ANTIBIOTIC PASTE AS INTRACANAL MEDICATION ON THE ELIMINATION OF ENTEROCOCCUS FAECALIS IN RETREATMENT CASES. A RANDOMIZED DOUBLE BLIND CLINICAL TRIAL
Introduction: The present study aimed to evaluate the effect of calcium hydroxide and the modified triple antibiotic paste (MTAP) as intracanal medication on the elimination of the Enterococcus faecalis in retreatment cases. Methods: Sixty patients who attended the outpatient endodontic clinic, faculty of oral and dental medicine, Cairo University were included in this research. Inclusion was limited to patients with symptomatic root canal treated teeth. All teeth underwent non-surgical retreatment. After removal of the gutta percha using protaper rotary retreatment files and irrigation with sodium hypochlorite, the canals were dried and one of the studied medicaments was inserted into the canal in a random sequence. The study was divided into 2 equal groups: Calcium Hydroxide group (CH group n=30) and modified triple antibiotic paste group (MTAP group n=30). Before application of the medicament, canals were sampled using paper points and the colony-forming units grown were counted. After 7 days, the medicaments were removed and the same sampling procedure was repeated. Obturation was then carried out. Results: For both groups, significant decrease in the colony forming units (CFU) of the Enterococcus faecalis resulted after material application. There was no significant difference in CFU between CH group and MTAP group after medication application. Conclusions: MTAP application resulted in decreased CFU of Enterococcus faecalis in nonsurgical retreatment endodontic cases. However there was no statistical significant difference between the use of calcium hydroxide and the modified triple antibiotic paste as intracanal medicament.
https://edj.journals.ekb.eg/article_92784_a1e8872e3e405a3073298c89022c76bf.pdf
2017-10-01
3683
3692
10.21608/edj.2017.92784
Calcium hydroxide
modified triple antibiotic paste
Enterococcus faecalis
retreatment
Alaa
El-Baz
1
Associate Professor, Endodontic Department, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
Geraldine
Ahmed
2
Associate Professor, Endodontic Department, Faculty of Oral and Dental Medicine, Cairo University
AUTHOR
ORIGINAL_ARTICLE
DETECTION OF PRESSURE AREAS FOR ELASTOMERIC IMPRESSIONS WITH AND WITHOUT SPACER USING NOVEL DIGITAL ANALYZING SOFTWARE AND ITS CORRELATION WITH RETENTIONA RANDOMIZED CLINICAL TRIAL
This study was conducted to evaluate the significance of using wax spacer in the impression technique regarding the pressure areas and retention of the complete dentures constructed. Forty patients with edentulous maxillary arches were selected from the outpatient clinic of removable prosthodontics department, faculty of oral and dental medicine, Cairo university .The patients were randomly divided into two groups. Group I received dentures constructed from impression technique with wax spacer while group II received dentures constructed from impression technique with no spacer. On the day of denture insertion pressure areas were detected using pressure indicating paste and denture retention was measured using force gauge. The data was collected and analyzed using student’s t-test. Results: The results showed the percentage of pressure areas for dentures constructed with no spacer were higher than those constructed with spacer showing statistically significant difference p
https://edj.journals.ekb.eg/article_76434_1a4de8199cc03a23370ed850c7bfa372.pdf
2017-10-01
3693
3698
10.21608/edj.2017.76434
complete denture
pressure areas
elastomeric impression
retention
Nancy
Elsherbini
1
Lecturer at the Removable Prosthodontic Department,Faculty of Oral and Dental Medicine, Cairo university.
AUTHOR
ORIGINAL_ARTICLE
STRESS ANALYSIS OF IMPLANTS RETAINED MANDIBULAR OVER DENTURE WITH BAR ATTACHMENT: COMPARATIVE STUDY WITH DIFFERENT CANTILEVER LENGTH (AN IN VITRO STUDY)
Abstract: This study was performed to compare between the stress distribution pattern of three implant retained bar attachment with different cantilever length.Materials & Methods: Acrylic model was constructed as a test model . Three root-form implants were placed two bilaterally in the canine region and one at the mid line of an edentulous acrylic mandibular model and connected with a resilient bar/clip attachment and attached to the over denture. The strain gauges made a tight contact with implant surfaces. A universal testing machine was used to exert a vertical pressure on the three implants and the strain rate of the implants was measured .The experiment was conducted in two phases: The first phase :(group I) the cantilever bar length was 5mm. The second phase: (group II) the cantilever bar length was 10mm. Micro strains recorded by vertical load applied to the cantilever bar framework were taken for both groups (group I as 5 mm bar and group II as 10 mm bar)..Results: The mean and standard deviation were calculated and tabulated for further statistical study labio-lingual and Mesio-Distal to the three implants in which the bar with clip was supported the over denture, for (group I) and (group II) there was significant increase of peripheral implants in micro strains than the central implant ,and( group II) revealed that there was significant increase of peripheral implants in micro strains when compare with (group I) , while there was insignificant increase in micro strains of the peripheral implants for both groups. Conclusion: The 5 mm cantilevered bar with clip was recommended when 3 implants were used to support mandibular over dentures as it demonstrated the lowest magnitude of strains on the central implant ,and regarding the peripheral implants of both groups there was no significant differences between peri -implant sites.
https://edj.journals.ekb.eg/article_76435_3484de47d5403746e04f47ba275f3895.pdf
2017-10-01
3699
3706
10.21608/edj.2017.76435
Implant supported over denture
bar attachment
Stress analysis
Mai
Helmy
1
Lecturer of Removable Prosthodontics Department, Faculty of Oral and Dental Medicine, Cairo University,
AUTHOR
Enas
Darwish
2
Lecturer of Removable Prosthodontics Department, Faculty of Oral and Dental Medicine, Cairo University,
AUTHOR
ORIGINAL_ARTICLE
BOND STRENGTH OF BULK-FILL COMPOSITE RESINS TO DENTIN WITH DIFFERENT ADHESION APPROACHES
Background and aim; Bulk fill resin composites have been proven in several studies to enable restoration in thick layers, up to 4mm, maintaining the mechanical properties and the degree of conversion within the whole increment. This study was designed to evaluate micro tensile bond strength (µTBS) of bulk-fill composite resins to superficial and deep dentin with different adhesion approaches. Materials and methods; Extracted human premolar teeth (n=24) were used to prepare 120 resin-dentin sticks. Specimens were divided into two main groups according to the type of bulk –fill composite used (Xtra fill & Tetric-N- Ceram). Each main group was subdivided according to the adhesive approach used into (total & self-etch). According to dentin depths each subgroup was further categorized into (superficial and deep). µTBS was evaluated using universal testing machine at a crosshead speed of 0.5 mm/min. Dentin / resin interfaces were assessed by scanning electron microscopy. Results; The results showed significant (p<0.05) effect of composite and dentin level on µTBS, while the effect of adhesive approach was non-significant (p>0.05). Conclusion; Xtra-Fill has higher µTBS than Tetric Bulk- fill. Total- etch adhesive system has higher µTBS than self-etch with the superficial dentin. Self-etch adhesive system has higher µTBS than total etch with the deep dentin.
https://edj.journals.ekb.eg/article_76436_510fb9f25539945110b72f20a0b34648.pdf
2017-10-01
3707
3716
10.21608/edj.2017.76436
Bulk-fill
Dentin
Bond
Adhesive approach
Nady
Ibrahim
1
Associate Professor, Operative Dentistry, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt.
AUTHOR
Muhammad
Samman
2
Associate Professor, Dental Biomaterials, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt.
AUTHOR
Hala
Fares
3
Assistant Professor, Operative Dentistry, Faculty of Oral and Dental Surgery, Misr University for Science and Technology,
AUTHOR
ORIGINAL_ARTICLE
APICAL HEALING, RESORBABILITY, AND DIGITAL RADIODENSITY AFTER APICAL EXTRUSION OF TOTALFILL VERSUS AH-PLUS SEALERS (ONE-YEAR RETROSPECTIVE STUDY)
Objectives: This one-year retrospective study evaluated the effect of unintentionally apically-extruded sealers (bioceramic versus epoxy-resin) on apical healing, sealers’ resorbability, and sealers’ digital radiodensity. Materials and Methods Thirty patients with root canal treatment showing unintentional apically-extruded sealer (n= 15 for TotalFill sealer, and n= 15 for AH-plus sealer) were included in the study. One-year recall radiographs were compared with immediate post-obturation ones for presence or absence of apical healing, and extruded sealer’s resorption, and digital radiodensity, using digital radiography. Data were statistically analyzed using Mann Whitney U-test and student-t test. Results: TotalFill recorded higher observations (1.67) of apical healing as compared to AH-Plus (1.2). The difference was statistically significant P≤ 0.05. Regarding sealer resorption, TotalFill recorded lower observations (0.06) as compared to AH-Plus (0.4). The difference was statistically significant P≤ 0.05. Digital radiodensity of TotalFill (37.46) was higher than that of AH-Plus (-19.73). The difference was statistically significant P≤ 0.001. Conclusions Within the limitations of the present study, TotalFill recorded higher observations of complete apical healing, compared to AH-Plus. TotalFill had a lower dissolution (resorbability) rate when compared to AH-Plus within the 12 months’ timeframe. Digital radiodensity of TotallFill increased by time when compared to the declining radiodensity of AH-Plus within the same period of time.
https://edj.journals.ekb.eg/article_76437_36e0fa1a0dbb20ba105a45dfa575cd38.pdf
2017-10-01
3717
3723
10.21608/edj.2017.76437
Root canal sealers
bioceramic sealers
TotalFill
epoxy-resin sealers
AH-plus
apical extrusion
apical healing
sealers’ resorbability
digital radiodensity
Mohammed
Atteia
1
Associate Professor of Endodontics, Department of Endodontics, Faculty of Oral and Dental Medicine, Cairo University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
STRESS ANALYSIS EVALUATION OF COMBINING RESILIENT ATTACHMENTS WITH DIFFERENT CANTILEVER BAR LENGTH ON SUPPORTING STRUCTURES OF IMPLANT SUPPORTED OVERDENTURE IN-VITRO STUDY
Four screw type implants(Pitt-easy Implant System, SIS, Germany) were placed in the interforaminal region of mandibular acrylic model then the abutments(Titanium sleeve abutment,Pitt –easy, Germany) intimately fitted over the hex of the implant. Two bar-ball designs were constructed on single model; Design I: Bar with yellow colored clips(Vario- Soft bar- Pattern VSP) connecting four implants with 8 mm distal cantilever bar extension with distally placed ball attachment (Patrix VKS - SG,Bredent,Germany) Design II: Bar with yellow clips connecting four implants with 16 mm distal cantilever with distally placed ball attachment. Two bar-ball designs were constructed on single model as follow: The bar connecting the abutments were held with mandrel, so that it’s rounded surface facing occlusally and its flat surface facing to the ridge. The wires of the strain gauges(Kaywan, Electronic Instrument, Tokyo, Japan) were embedded in specially prepared channels in the base of the model. The straight load applicator bar of the universal testing machine(LLyod Instruments, Japan) was allowed to touch the denture teeth. Vertical unilateral loading was applied unilaterally at the central fossae of the left second premolar.All data of the study were collected and statistically analyzed. Using student T test to compare between two designs, it is found that there is statistically significant difference between design I and design II. The result obtained from this study showed that there is increase in the stresses applied to the nearby abutment this was due to the distal extension that act as hidden cantilever which add to bending moment and the fact that in design II the bending moment will decrease, thus decreasing the amount of force on the abutment.
https://edj.journals.ekb.eg/article_76438_1052566be572db0e95968f75f9dcf020.pdf
2017-10-01
3725
3730
10.21608/edj.2017.76438
Ahmed
Mahrous
1
Lecturer of Removable Prosthodontics , Faculty of Dentistry, October 6 University. Egypt
AUTHOR
ORIGINAL_ARTICLE
MARGINAL BONE LEVEL EVALUATION OF IMPLANT SUPPORTED KENNEDY CLASS I PARTIAL OVERDENTURE USING TELESCOPIC CROWNS VERSUS EXTRA CORONAL ATTACHMENT RETAINERS
Objectives: This study was conducted to evaluate and compare marginal bone level for abutments of implant supported Kennedy class I partial overdenture using Telescopic Crowns versus OT unilateral attachment after 18 month of clinical use. Materials and Methods : Ten male partially edentulous patients (Kennedy class I) with the premolars are the last standing abutments were selected and all patients were rehabilitated with metallic partial denture supported by two osseointegrated implants one on each side of the lower arch positioned in the area of second molar and were randomly divided into two equal groups according to type of abutments retainers, Group I; Patients were rehabilitated with Tooth Implant Supported partial overdenture with two telescopic crowns at each side, Group II: Patients were rehabilitated with Tooth Implant Supported partial overdenture with extra coronal OT attachments. The two groups are evaluated by measuring marginal bone level for main abutments. Measurements were made at the time of insertion, after 6 months, after 12 months and last after 18 month using radiographic evaluation. Results: Partial overdentures retained by telescopic crowns showed no significant difference in marginal bone loss as compared with extracoronal OT attachments retainers. Conclusion: Using tooth implant partial overdentures retained by extracoronal OT unilateral attachments shows better effect on supporting structure as compared by partial dentures with telescopic crowns retainers
https://edj.journals.ekb.eg/article_76439_52ef4f611475dd1d02face24884832e5.pdf
2017-10-01
3731
3737
10.21608/edj.2017.76439
Ahmed
Shaaban
1
Lecturer of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Future University
AUTHOR
Aya
Fawzy
2
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine, Al-Azhar University, Assiut Branch
AUTHOR
Mahmoud
Ammar
3
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine, Al-Azhar University, Assiut Branch
AUTHOR
ORIGINAL_ARTICLE
OUTCOMES OF FLEXIBLE PARTIAL DENTURE WITH ESTHETIC CLASPS AS AN IMPLANT PROVISIONAL PROSTHESIS IN THE ANTEROR MAXILLA
introduction: A patient submitted to delayed loading protocol ought to be given a provisional restoration at the interval between the first and second phase of implant therapy. This provisional restoration is made to satisfy the prerequisites of mastication, aesthetics, & to reduce the psychological trauma associated with teeth loss. The reason for this examination was to assess clinical & radiographic outcomes of the provisionally-used flexible removable partial denture (RPD) on both; the implants placed as well as the adjacent abutment teeth. Materials & methods: For the outcome of this clinical research study, ten patients with lost teeth in the anterior maxilla were treated by implant placement. Directly following sutures removal & gingival healing, every single patient received new flexible provisional RPD with aesthetic clasps (resting on adjacent abutment teeth) being fabricated in the usual manner. and mandibular complete dentures prior to implant placement. After common denture delivery adjustments, every patient was instructed to use the denture in a conventional manner for six months, with a follow-up appointment every month. After six months of implants placement (to ensure complete implants osseointegration), patients completed the implant restoration phase till receiving anterior fixed restorations. Clinical & radiographic outcomes for the implants and the abutments were measured Three times (at time of insertion, three months and six months, respectively)Results: For parametric data; Repeated measures Analysis of Variance (ANOVA) was used to study the changes by time, while for non-parametric data; Friedman’s test was used to study the changes by time. Those studies revealed that: There was no statistically significant changes in mean clinical & radiographic measurements around both the implants & the abutments throughout the whole study period. Conclusion: Using flexible RPD with aesthetic clasps as a provisional restoration during the period of implants osseointegration was favourable and preserved the health of supporting structures of the abutment teeth as well as the implants, in addition to enhanced aesthetics & psychological confidence of the patients.
https://edj.journals.ekb.eg/article_76440_7e965f95406ed93a4c8be0d715ce5ed8.pdf
2017-10-01
3739
3754
10.21608/edj.2017.76440
Flexible denture
Acetal Resin
Dental implants
Provisional restoration
aesthetics
Mostafa
Ahmed
1
Lecturer of Removable Prosthodontics, Faculty of Dentistry, Cairo University.
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF THERMAL CYCLING ON MARGINAL SEAL OF DIFFERENT DENTIN SUBSTITUTES
Objectives: To investigate the marginal seal of new dentin substitutes using environmental SEM and evaluate the longevity of the seal after being subjected to thermal stresses. Methods: Four different dentin substitute materials (SDR, DENTSPLY; Sonic Fill, Kerr; Filtek Bulk Fill, 3M ESPE; and Fuji II LC, GC Corporation) were tested in this study. MOD cavities (4mm depth and half of the intercuspal distance width) were prepared on eighty human sound extracted premolars. Teeth were divided randomly into four groups according to the tested material. Each group was further divided into two subgroups (n=10): subgroup A; No thermal cycling was applied, and subgroup B; was subjected to thermal cycling (5±2 ºC - 55±2 ºC for 1000 cycles). The teeth were sectioned vertically through the resin composite parallel to their long axis in mesiodistal direction. Specimens were then tested for gap formations along pulpal dentin interface using Environmental SEM. Data were tabulated and statistically analyzed. Results: Regardless of thermal cycling; Fuji II showed the statistically significantly highest mean gap distance (26.6 ± 12.6). Sonic Fill showed statistically significantly lower mean value (23.4 ± 4.3). There was no statistically significant difference between Bulk Fill (17.5 ± 1.7) and SDR (16.3 ± 1.5); both showed the statistically significantly lowest mean gap distance. Without thermal cycling, Sonic Fill showed the statistically significantly highest mean gap distance (19.4 ± 1.2). No statistically significant difference was found between Filtek Bulk Fill (16.1 ± 1.0), SDR (15.3 ± 0.9) and Fuji II (14.6 ± 0.7); all showed the statistically significantly lowest mean gap distances. While with thermal cycling, Fuji II (38.5 ± 0.9) showed the statistically significantly highest mean gap distance. Sonic Fill showed statistically significantly lower mean value (27.3 ± 0.9). There was no statistically significant difference between Filtek Bulk Fill (18.9 ± 0.7) and SDR (17.4 ± 1.2); both showed the statistically significantly lowest mean gap distance. Conclusions: Under the test conditions, Bulk Fill and SDR provided an adequate marginal seal, regarding gap distance, when compared to Sonic Fill and Fuji II. Meanwhile, thermal cycling significantly increases gap distance in all tested dentin substitutes, thus affecting longevity.
https://edj.journals.ekb.eg/article_76441_c93ec0dfae6466b2d658ba0e905143d2.pdf
2017-10-01
3755
3766
10.21608/edj.2017.76441
Dentin substitutes
gap distance
sealing
thermal cycling
longevity
Bulk Fill
Sherif
Bahgat
drsherifbahgat@hotmail.com
1
Fixed Prosthodontics Department, October University of Modern Sciences and Arts, Faculty of Dentistry, Cairo, Egypt.
AUTHOR
Abeer
Abo El Naga
2
Doctorate of Operative Dentistry, Faculty of Dentistry, Cairo University, Cairo, Egypt.
AUTHOR
Rasha
Basheer
3
Operative Dentistry Department, October University of Modern Sciences and Arts, Faculty of Dentistry, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
ASSESSMENT OF ACCURACY OF DIFFERENT CAD/CAM FABRICATED PORCELAIN LAMINATE VENEERS
Objectives: The aim of the current study was to compare the accuracy of different restorative materials currently used in porcelain laminate veneers (PLV) fabrication, in terms of external and internal adaptation, and to evaluate the longevity of the PLV seal in response to thermocycling, in terms of microleakage. Methods: 30 (PLV) preparations were performed on maxillary central incisor to be restored with restorations fabricated by milling ceramic blocks using a CAD/CAM system. Samples were divided randomly into three groups (n=10) according to the restorative material ([Prettau, Zirkonzahn, Pustertal, Italy], [IPS e.max CAD, Ivoclar, Schaan, Liechtenstein] and VITA SUPRINITY, VITA Zahnfabrik, Bad Sackingen, Germany]). The veneers were cemented using total-etch resin cement according to manufacturer instructions, then subjected to artificial aging program after which they were immersed in basic fuchsine dye for 24 hours. All specimens were sectioned in labio-lingual direction using a precision cutting machine, and vertical gap distance, internal adaptation, and dye penetration were measured using stereomicroscope. Data were statistically-analyzed using one-way ANOVA, two-way ANOVA, Tukey’s post-hoc and Student t-tests (P≤0.05). Results: The highest statistically significant marginal gap distance and lowest internal adaptation values were recorded with Prettau group followed by IPS e.max CAD group while the lowest statistically significant marginal gap distance and highest internal adaptation values were for VITA SUPRINITY group. For the microleakage, the highest statistically significant leakage values were recorded with IPS e.max CAD group followed by Prettau group. The lowest statistically significant leakage values were for VITA SUPRINITY group. Irrespective of material’s group, it was found that incisal margin recorded statistically significant higher marginal gap distance mean values than cervical one. For the microleakage, the reverse was found. Conclusions: Under the test conditions, the following could be concluded: 1. All ceramic materials used in this study were within the clinically acceptable range of marginal accuracy. 2. CAD/CAM technology does not necessarily present highly accurate restorations, in terms of external and internal adaptation. 3. Lithium disilicate-based restorations showed better external and internal adaptation, and microleakage than monolithic Zirconia-based restorations. 4. The correlation between external and internal adaptation and microleakage is still questionable.
https://edj.journals.ekb.eg/article_76442_7c6540b911e8d48ec60960579ab9c280.pdf
2017-10-01
3767
3781
10.21608/edj.2017.76442
Monolithic Zirconia
Lithium Disilicate
marginal accuracy
microleage
internal adaptation
Rasha
Basheer
1
Operative Dentistry Department, Modern Science and Arts University, Faculty of Dentistry, Cairo, Egypt.
AUTHOR
Shereen
Elsayed
2
Fixed Prosthodontics Department, Cairo University, Faculty of Dentistry, Cairo, Egypt
AUTHOR
Sherif
Bahgat
drsherifbahgat@hotmail.com
3
Fixed Prosthodontics Department, Modern Science and Arts University, Faculty of Dentistry, Cairo, Egypt
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF PALATAL COVERAGE AND NUMBER OF MINI IMPLANTS USED TO ASSIST MAXILLARY OVERDENTURE: AN IN VITRO STUDY OF RETENTION, CYCLIC FATIGUE AND DEFORMATION OF MAXILLARY OVERDENTURE BASE
Purpose : Prosthodontic complications related to implant assisted maxillary overdentures are reported more often. This in vitro study examined the influence of implant number and palatal coverage on retention, cyclic fatigue and denture base deformation of maxillary overdentures supported by five versus seven unsplinted mini implants.Materials and methods: An edentulous model of maxillary arch with mini diameter implant dummies was fabricated. The implants were inserted into the anterior, premolar, and molar areas. Maxillary experimental dentures with complete and partial palatal coverage were fabricated. Cyclic dislodging forces were applied to assess cyclic fatigue and the resulting change in denture retention. Strain gauges were used to assess the deformation induced into the dentures when cyclic fatigue test was carried out on overdentures assisted by seven implants and five implants after excluding the posterior implants. Results: Cyclic fatigue and denture base deformation induced in overdentures with partial palatal coverage assisted by five mini implants were significantly higher than overdentures with complete palatal coverage whether assisted by seven or five implants (P < .05). Overdentures with partial palatal coverage assisted by seven mini implants exhibited non-significant changes in retention, cyclic fatigue and base deformation when compared to overdentures with complete palatal coverage assisted by five mini implants.Conclusion: Maxillary five mini implant assisted overdentures with partial palatal coverage revealed much higher cyclic fatigue and induced denture base deformation than overdentures with complete palatal coverage regardless of the mini implant number. With respect to retention, fatigue failure and denture deformation, maxillary seven mini implant assisted overdentures with partial palatal coverage exhibited no significant difference comparable to five mini implant assisted maxillary overdenture with complete palatal coverage.
https://edj.journals.ekb.eg/article_76443_0fb297e7e601b084e55294550d149344.pdf
2017-10-01
3783
3798
10.21608/edj.2017.76443
Mini implant
maxillary implants overdenture
partial palatal coverage
cyclic fatigue
deformation
Fatma
El-Waseef
1
Lecturer of Removable Prosthodontics, Faculty of Dentistry, Mansoura University
AUTHOR
Amira
Gomaa
2
Assistant professor of Removable Prosthodontics, Faculty of Dentistry, Mansoura University
AUTHOR
ORIGINAL_ARTICLE
CHANGES IN ORAL-HEALTH IMPACT PROFILE (OHIP) OF IMPLANT SUPPORTED MANDIBULAR PARTIAL OVERDENTURES IN RELATION TO IMPLANT POSITION AND SUPPORT
Background: Complete and partial tooth loss have been reported to have an adverse impact on patient appearance, phonetics, masticatory function, in addition to affecting the patient’s quality of life and general health. Removable partial denture have been the most commonly used treatment option for the replacement of missing teeth, yet it offers disadvantages with regard to retention and stability. The use of dental implants especially in free end saddle cases using the overdenture approach, have improved both retention and stability. The clinical success of implant supported prosthesis have been documented but its impact on the quality of life needs to be investigated. The OHIP-49 was used to determine the impact of oral health conditions on aspects of daily function, social interactions in seven domains. The aim of this clinical trial is to evaluate the changes in the oral health related quality of life of partially edentulous patients in relation to implant position and implant support, by installing two implants in a free end saddle and using an implant supported removable partial overdenture.Materials and Methods: 14 partially edentulous patients of Kennedy class II modification 1 were selected from the outpatient of the Prosthodontics clinic –Cairo University. All patients were ranging from age 45-65 years old. All patients in the study were seeking implant installation with their remaining dentition in good periodontal health to receive a metal framework removable partial denture after all necessary operative procedures carried out. Patients with any contra-indications to implant placement were excluded from the study. All patients have received two implants in the pre-molar and molar regions of free end saddle region. After three month from implant installation, a secondary stage surgery was carried out and the two implants have received a healing abutment. A metal framework partial denture was then fabricated and delivered to all patients, supported by two healing abutments which was considered to be the base line group. After three month from delivery of the metal partial denture all patients were asked to fill the OHIP-49 chart, and then the patients were randomly divided into two groups the first group received a ball attachment at the premolar region, and the second group received a ball attachment at the molar region. The OHIP-49 was translated into Arabic and then filled by both groups after a 3 month follow up. Results: There was no statistically significant difference of the total mean score of the OHIP-49 chart among the three groups of patients; base line group, first group and second group. The base line group have shown a non-significant decrease in the quality of life which was then improved by installation of a ball attachment in the first and second group, having the most non-significant improvement in the second group of patients. There was also a non-statistically significant difference of the seven subscales of the OHIP-49. The functional limitation, and physical pain of the OHIP-49 chart have shown the most improvement in the second group of patients when compared to the rest. Physical disability and Handicap subscales of the OHIP-49 chart were similar for the first and second groups, only the handicap encountering great improvement in the quality of life for base line group than the other two groups. While the Psychological discomfort, Physiological disability and Social disability were similar for all the three groups of patients. Conclusion Implant supported removable partial denture with a ball attachment installed would improve the patient’s quality of life when compared to an implant tooth-tissue removable partial denture supported by healing abutments. There was no statically significant difference in the quality of life total scores with installation of a ball abutment at either the pre-molar or molar region, but a non-significant improvement in the quality of life have been encountered at the ball attachment installed in the molar region.
https://edj.journals.ekb.eg/article_76444_4eeadf1850284ae34762a0dcf433a722.pdf
2017-10-01
3799
3811
10.21608/edj.2017.76444
Nouran
Nabi
1
Lecturer in Removable Prosthodontics, Cairo University
AUTHOR
ORIGINAL_ARTICLE
T-SCAN EVALUATION OF INJECTION VERSUS COMPRESSION MOLDED MAXILLARY COMPLETE DENTURES OPPOSED BY IMPLANT RETAINED MANDIBULAR OVERDENTURES
Objectives: This research was carried out to evaluate the bite force distribution of the maxillary complete dentures processed by injection molded (IM) and compression molded(CM) techniques opposed by implant retained over denture(IOD) using T-scan. Materials and Methods: Ten completely edentulous patients were rehabilitated by mandibular (IOD) and maxillary complete denture. Each patient received two maxillary dentures, one was formed of thermoplastic acrylic resin processed by (IM) technique and the other was formed of conventional acrylic resin processed by (CM) technique. The bite force distribution on the two maxillary dentures was evaluated by T-scan one week and three months after denture insertion.Results: In this study, at the end of the follow up period there was statistically significant difference in the bite force distribution between the (IM) &(CM) complete dentures. After one week of denture insertion, the means of difference of bite force distribution between the right and left posterior edentulous areas of (IM) &(CM) complete dentures were (7.700±3.860) and (15.80 ±4.984) consequently. While the means of bite force distribution for anterior edentulous areas of (IM) &(CM) complete dentures were (10.80 ±2.658) and (17.60 ±3.239) respectively. After three months, the means of difference of bite force distribution between the right and left posterior edentulous areas of (IM) &(CM) complete dentures were (9.400±4.695) and (18.40 ±7.106) consequently, and the means of bite force distribution in the anterior region were (16.40 ±2.591) and (23.80 ±3.824) in (IM) &(CM) complete dentures respectively.Conclusion: Within the limitation of this study, it could be concluded that IM complete dentures showed even bite force distribution along the posterior area of both sides of the edentulous arch and less bite force on the anterior edentulous area compared by CM complete denture. Both dentures showed increased bite force distribution by time on the anterior edentulous area.
https://edj.journals.ekb.eg/article_76445_9757541c45904be074aea6dc36961853.pdf
2017-10-01
3813
3821
10.21608/edj.2017.76445
dental implant
maxillary
mandibular overdenture
injection molded
compression molded
bite force distribution and T-Scan
Shaimaa
Lotfy
1
Lecturer of Removable Prosthodontics, Faculty of Dentistry Ain Shams University.
AUTHOR
Rehab
Alaswad
2
Lecturer of Removable Prosthodontics, Faculty of Dentistry Misr International University.
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF TWO DIFFERENT RESTORATIVE MATERIALS ON STRESS DISTRIBUTION ON ALL-ON-FOUR IMPLANT RETAINED RESTORATIONS
Purpose: The purpose of this in vitro study was to evaluate the effect of restorative material either zirconia or BioHPP on stress distribution affecting periimplant supporting structures.Materials and methods: Four implants were installed using a surveyor in a maxillary model. Scan bodies were used to scan implant fixture position using identica hybrid desktop scanner then Exocad software was used to design a cutback implant retained restoration. VHF 5 axis milling machine was used for manufacturing of zirconia & bioHPP restoration from the same STL design, veneering was then performed by feldspathic porcelain & composite respectively. Strain gauge was installed 1mm distal to implant fixture. Universal testing machine was used to apply both axial & off axial loads 100 N & microstrains were recorded to test amount of developed strain around implant. Results: The results of independent t test showed that there was no statistically significant effect between bioHPP and Zirconia groups under axial loading (p= 0.064) and off axial loading (p=0.11) Conclusions: Based on the present in vitro results, the change in restoration material did not affect the stress distribution in implants and peripheral bone under axial & off axial loads.
https://edj.journals.ekb.eg/article_76446_f01af0be595852a3c966576c5e8db8ef.pdf
2017-10-01
3823
3832
10.21608/edj.2017.76446
Ahmed
Sabet
1
Lecturer, Fixed Prosthodontics Department, Ain Shams University
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF FILLING PULP CHAMBER ON MARGINAL ADAPTATION AND FRACTURE RESISTANCE OF ZIRCONIA REINFORCED GLASS CERAMIC ENDOCROWN RESTORATIONS
Purpose: The purpose of this in vitro study was to evaluate the marginal adaptation and the fracture resistance of endodontically treated molars restored with zirconia reinforced glass ceramic endocrown restoration with or without incorporating a fiber-reinforced composite (FRC) layer into the pulp chamber.Materials and methods: Mandibular first molars (n= 30) were prepared by computerized numerical control (CNC) in a standardized way to receive standardized CAD/CAM fabricated zirconia reinforced glass ceramic endocrowns after root canal treatments. The selected teeth were divided into two groups (n=15) according to the presence of fiber reinforced composite (FRC) in the pulp chamber. Group NF (Non filled) represented teeth with the pulp chamber without filling and Group F (Filled)represented teeth with the pulp chamber filled with FRCs. Marginal gaps (µm) were measured using stereomicroscope (32x) before cementation and after cementation. Thermal aging (3000 cycles) was performed then marginal gaps measurements were repeated. Then, fracture resistance test was performed. ANOVA test was used to study the interactions while Independent t-test was used to study the effect of using FRCs in the pulp on marginal adaptation in each stage and on the fracture resistance (N).Results: The results of independent t test showed that there was no statistically significant effect of incorporating FRCs into the pulp chamber on the marginal adaptation during all stages before (p= 0.844) or after cementation (p=0.884) or after thermocyclying (p=0.875). Regarding the fracture resistance, the test showed that Group NF had higher mean fracture load value than Group F and the difference was statistically significant (p=0.004)Conclusions: Within the limitation of this study, the incorporation of FRCs into the pulp chamber of endodontically treated teeth restored with zirconia reinforced glass ceramic endocrowns had no influential effect on the marginal adaptation of the restoration before or after cementation or after thermocycling. However, the presence of the FRCs unexpectedly decreased the mean values of the fracture resistance of the restorations. Further investigations are needed to confirm these findings before clinical application.
https://edj.journals.ekb.eg/article_76448_074a2973e775ad01c869aa6f06fa00e8.pdf
2017-10-01
3833
3842
10.21608/edj.2017.76448
Ahmed
Sabet
1
Lecturer Fixed Prosthodontics Department, Ain-Shams University
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF ANTIOXIDANTS ON THE BOND STRENGTH OF RESIN COMPOSITE TO BLEACHED ENAMEL
Aim : This study aimed to assess the effect of treating bleached enamel with antioxidants on the value of shear bond strength of resin composite to enamel. Also, a comparison was set between the natural antioxidant used (5% pomegranate solution) and the chemical one (10 % sodium ascorbate gel). Materials and Methods: Fifty six human freshly extracted sound upper anterior teeth were used. The specimens were randomly divided into four main groups as follow : Group I : control(no bleaching) ; Group II : bleached then treated with the chemical antioxidant ; Group III : bleached then treated with the natural antioxidant; Group IV : bleached with no antioxidant treatment. Each group was further sub-divided into two sub-groups according to whether the restoration was performed immediately or delayed (after one month incubation in artificial saliva) (n=7). The variables were as follow: No bleaching immediate restoration (control) ; no bleaching delayed restoration after incubation for one month in artificial saliva ; bleached followed by application of a chemical antioxidant (10% sodium ascorbate gel) for 10 min then immediate restoration;bleached followed by application of a chemical antioxidant (10% sodium ascorbate gel) for 10 min then delayed restoration; bleached followed by application of a natural antioxidant (5% pome granate solution) for 10 min then immediate restoration ; bleached followed by application of a natural antioxidant (5% pome granate solution) for 10 min then delayed restoration ; bleached with no application of an antioxidant then immediate restoration ; bleached with no application of an antioxidant then delayed restoration. The data were statistically analyzed using two way ANOVA test, one way ANOVA test, Tuckey’s post-hoc tests and pair wise student T-test. Results : Regarding the mean shear bond strength values (immediate restoration) ; the control sub-group (immediately restored) demonstrated the highest values followed by the bleached sub-groups treated with the natural antioxidant (5% pomegranate solution), then the bleached sub-groups treated with the chemical antioxidant (10% sodium ascorbate gel). The bleached sub-groups that were not treated with the antioxidants showed the least values. Regarding the sub-groups that undergone a delayed investigation ; the sub-groups treated with the natural antioxidant demonstrated the highest shear bond strength values followed by the sub-groups treated with chemical antioxidants then the control group while the bleached sub-groups that were not treated with the antioxidants showed the least values of mean shear bond strength
https://edj.journals.ekb.eg/article_76449_6e437f8f69ae2b00194545856b418ac0.pdf
2017-10-01
3843
3851
10.21608/edj.2017.76449
antioxidants
bond strength – bleached enamel
Hala
Fares
1
Assistant Professor, Operative Dentistry, Faculty of Oral and Dental Surgery, Misr University for Science and Technology.
AUTHOR
Muhammad
Samman
2
Associate Professor, Dental Biomaterials, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt.
AUTHOR
Saad Eldin
El Ghazawy
3
Lecturer, Dental Biomaterials, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF SHORT TERM WATER STORAGE ON FRACTURE TOUGHNESS AND MICRO HARDNESS OF A LOW-SHRINKAGE SILORANE AND DIMETHACRYLATE BASED NANOHYBRID COMPOSITES
Objectives: The purpose of this study was to assess the effect of water storage on the fracture toughness (K1C), and micro-hardness of a low shrinkage silorane based and a nanohybrid dimethacrylate composite resin materials.Materials and Methods: Two types of composite resins were selected: nano hybrid methacrylate based (Grandio) and microhybrid silorane based (Filtek P90). For fracture toughness test, a total of 40 single edge notched bar-shaped specimens were prepared and stored in distilled water for 24hrs and 6 weeks. The effect of water uptake on fracture toughness following each storage regimen was determined by loading the specimens to failure in a 3-point flexure strength test setup using a universal testing machine. For Vickers hardness test, 40 disc shaped specimens (height 2 mm, diameter 5 mm) were prepared from each composite material and subjected to testing after 24 hours and six weeks of water storage. The fractured surface was examined using scanning electron microscopy (SEM) to determine the failure pattern following both storage periods.Results: Statistical analysis (T=8, p<0.0001) revealed that the 24hrs fracture toughness of Silorane was singnificantly higher (1.65±0.12 MP a.m1/2) than Grandio (1.11±0.12 MP a.m1/2). After six weeks storage in water the two materials showed a significant decrease (T=13.5, P<0.001) in fracture toughness with Silorane still exhibiting a higher fracture toughness (1.22±0.07 MPa.m1/2) compared to Grandio (0.56 ± 0.08 MPa.m1/2). Silorane showed a highly significant difference in VHN (67.18±1.33) compared to Grandio (42.37±0.73) at the 24 hrs period. After 6 weeks storage in water, a significant decrease was observed in VNH of Grandio (30.55±0.71) while Silorane did not show any decrease in VHN (67.44±1.16). SEM imaging findings were consistent with the results Conclusions: Within the limitations of this study, Silorane P90 exhibited higher fracture toughness and microhardness compared to Grandio nanohybrid composite in both storage periods. Although water storage decreased fracture toughness of Silorane it still remained significantly higher than Grandio. VHN of Silorane was not significantly affected by water storage after six weeks, while, Grandio showed a highly significant decrease in VHN following water storage.
https://edj.journals.ekb.eg/article_76450_5d6d410392766beda087bdb7231eb0f9.pdf
2017-10-01
3853
3862
10.21608/edj.2017.76450
Maha
Motie
1
Assisstant Professor, Dental Biomaterials, Faculty of Dentistry, Alexandria University, Egypt
AUTHOR
ORIGINAL_ARTICLE
EFFECTIVENESS OF DIFFERENT CHEMICAL CLEANSERS AND DISINFECTANTS ON THE TRANSVERSE STRENGTH OF DIFFERENT DENTURE BASE MATERIALS
Denture wearers are strongly urged to practice regular oral and denture hygiene to maintain good oral and general health. Denture cleansing by chemical agents is an easily practiced method that requires simply the immersion of the denture in a commercially available solution according to the manufacturer’s instructions. In selecting a disinfectant for dental prosthesis, compatibility between the disinfectant and the type of denture base material must be considered to avoid adverse effects in it. The aim of this study is to evaluate the effect of over the counter denture cleansers on the transvers strength of three denture base materials. Heat cure acrylic rein, self cure acrylic rein and the Thermoplastic groups specimens were immersed for one week (5 hours per a day) in peroxide effervescent denture cleansers (Corega Tabs, & Fittydent) and finally 2% Chlorhexidine. Distilled water was used as the control group. Transvers strength was measured using three-point bending test in a universal testing machine. Data were analyzed with ANOVA and Post-hoc Tukey’s tests. The results showed multi variance analysis revealed high significance p ≤ 0.005 for solutions and resin types, and the interaction of these factors on transverse strength. Conclusion: transverse strength of denture base material can be altered by the disinfectant solutions tested as well as by the type of resin.
https://edj.journals.ekb.eg/article_76451_c5ed2877cdf8c026774e19261bdc62bb.pdf
2017-10-01
3863
3871
10.21608/edj.2017.76451
Chemical cleansers, Disinfectants
Denture base materials
Thermoplastic
Transverse strength
Iman
Matar
1
Lecturer, Department of Prosthodontics, Faculty of Dentistry , Pharos University, Alexandria, Egypt
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF TWO TECHNIQUES OF COMPLETE DENTURE CONSTRUCTION ON THE MUSCLE ACTIVITY AND OCCLUSAL LOAD
Objective: to evaluate the effect of two techniques of denture construction on the muscle activity using electromyography the occlusal load using T-scan.Materials and method: Twenty completely edentulous patients were selected and allocated into two groups: Group I: The upper and lower denture were processed in the usual manner and delivered to the patient. Group II: The upper waxed denture we processed only then remounted against the waxed lower denture any occlusal adjustment was done in the lower waxed denture then the processing the lower denture was performed - Electromyography recording were performed with the patient seated in relaxed upright position. -Electromyography recording device was used to evaluate the action potential of the masseter and anterior fibers of temporalis muscle. -The T-scan III was used for bite force measurement to detect the location, timing and magnitude of occlusal forces.Results: There was statistically significant difference between both groups during chewing soft and hard food diet for masseter and temporal is muscles. The highest mean differences muscle activity were recorded for patients received conventional denture while the lowest values recorded for patients received denture in muscle activity of group II.Conclusion: The Schlosser’s technique is considered as predictable methods of complete denture construction. The more harmonious occlusion result from this technique results in an improvement of the muscle activity and biting force.
https://edj.journals.ekb.eg/article_76452_e87b339ab43431f75e50bbd4c0ae533f.pdf
2017-10-01
3873
3878
10.21608/edj.2017.76452
Noha
Abdelaa
1
Lecturer of Removable Prosthodontics Department, Faculty of Oral and Dental Medicine, Cairo University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF RETENTION AND MICROBIAL COLONIZATION OF TWO DIFFERENT DENTURE BASE MATERIAL
The aim of this study: Is to evaluate the effect of conventional heat cure acrylic resin denture base and thermoplastic resin base on the retention and bacterial colonization in complete dentures. Material and methods: Twenty completely edentulous patients were selected and randomly grouped into two equal groups: group I received maxillary and mandibular complete dentures made of conventional heat-cured acrylic resin, group II received maxillary and mandibular complete dentures made of thermoplastic resin. The retention mean values were measured for mandibular dentures for both groups at time of denture insertion and after 3 months by using the universal testing machine. Assessment of microbial colonization in the two denture base materials was done after 3 and 6 months from denture insertion. The isolation of microorganisms was done with gamma sterilized disposable swabs from tuberosity area under the fitting surface of the maxillary dentures, each swab cultivated in three culture media. The tested microorganisms are Candida albicans (C. albicans), Streptococcus mutans (S. mutans), Staphylococcus aureus (S. aureus) and mixed Streptococcus and Candida. Results: The thermoplastic resin denture showed statistically significant higher mean of retention value than conventional heat cure denture at insertion and after 3 months (P value <0.000). The microbial colonization results revealed significant difference between group I and group II in the count of C. albicans, S. mutans and mixed Streptococcus after 3 months and 6 months. The thermoplastic resin base (group II) showed decreased microorganism count than group I (heat cured acrylic resin base) while S. aureus count showed no statistically significant difference between the two groups.Conclusion: Thermoplastic resin denture bases showed better retention and less microbial colonization than conventional heat cure acrylic resin. Further studies are recommended to evaluate the long-term quality of retention and biological properties of thermoplastic resin complete dentures and its impact on patients’ satisfaction.
https://edj.journals.ekb.eg/article_76453_ae92419512bc6e38b33d5d476d1ede76.pdf
2017-10-01
3879
3887
10.21608/edj.2017.76453
Denture base material
retention
and Bacterial colonization
Shereen
Kabeel
1
Lecturer of Removable Prosthodontics, Faculty of Dental Medicine for Girls, Al-Azhar University.
AUTHOR
Dina
Kholief
2
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine for Girls, Al-Azhar University.
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF ADAPTATION AND STRESS INDUCED BY DIFFERENT DESIGNS OF PALATAL MAJOR CONNECTORS
The purpose of this in-vitro study was to evaluate adaptation and stresses induced over the abutment teeth and residual ridge through different designs of maxillary major connectors.Materials and methods: An acrylic resin model was fabricated and three different designs of upper major connectors were constructed, the first design was anterior palatal strap, the second design was anterior palatal bar and the third design was anterior-posterior palatal strap. Stress analysis was evaluated using strain gauge and strain developed was recorded. The adaptation was measured by Leica Micro System LTd, made in Germany. Data were calculated, tabulated and analyzed using statistical ANOVA test to compare between the last 10 readings obtained from the different designs when unilaterally and bilaterally loaded. Data were presented as mean and standard deviation (SD) values. Results: The results revealed that the stresses transmitted to the abutments teeth and residual ridge by the anterior palatal bar major connector was of lower values than those recorded when the anteroposterior and anterior palatal strap were used. Regarding the adaptation of the major connectors no significant differences occurred before or after loading.Conclusion: It can be concluded that much higher stresses transmitted by the anteroposterior palatal strap and the anterior palatal strap than that transmitted by the anterior palatal bar. Future research should focus on the minimal dimensions for relevant major connectors’ adaptation.
https://edj.journals.ekb.eg/article_76454_d4fe650e5fd4f80cc1fbd78b7b52ad7c.pdf
2017-10-01
3889
3894
10.21608/edj.2017.76454
Noha
Gamal-Eldin
1
Lecturer of Removable Prosthodontics Department, Faculty of Oral and Dental Medicine, Cairo University, Cairo, Egypt.
AUTHOR
Enas
Darwish
2
Lecturer of Removable Prosthodontics Department, Faculty of Oral and Dental Medicine, Cairo University, Cairo, Egypt.
AUTHOR
ORIGINAL_ARTICLE
INFLUENCE OF ENDOCROWN PULPAL EXTENSION ON STRESS DISTRIBUTION IN ENDODONTICALLY TREATED MAXILLARY PREMOLARS A THREE-DIMENSIONAL FINITE ELEMENT ANALYSIS
Purpose: Although endodontically treated molars restored with endocrowns have been reported to be clinically successful, clinical and in vitro studies indicated more frequent problems with endodontically treated premolars restored with endocrowns. The aim of this finite element study was to evaluate the influence of the pulpal extension on the stress distribution in endodontically treated maxillary premolars restored with endocrowns.Materials and methods: An intact maxillary first premolar tooth without any obvious abnormalities or decay was scanned using Planmeca ProMax 3D Mid cone-beam CT machine, the 3D models of enamel and dentin were then segmented using MIMICS software. Three design models were created as follow: Model (A) represented the classical ceramic crown with glass fiber reinforced post and a composite resin core , model (B) represented the endocrown preparation of a circular butt-margin with the depth of the central retention cavity extending 5 mm in depth from the occlusal floor, and model (C) represented the endocrown preparation of a circular butt-margin with the depth of the central retention cavity extending 3 mm in depth from the occlusal floor. Bone geometry was simplified and simulated as a cylinder that consisted of an outer shell of compact bone and an inner core of trabecular bone. All the design models where remeshed and exported to Ansys Workbench as volume meshes for the finite element analysis. The base of the bony cylinder was selected as a fixed support, and an axial oblique load of 100 N was applied to each model. Material properties were assigned for every model, and static structural analysis was performed. Conclusions: Within the limitations of this finite element study, it was concluded that endocrowns offered a viable alternative for restoration of endodontically treated maxillary premolars, and increasing the pulpal extension to 5 mm significantly increased the stress distribution in the endocrown under axial forces.
https://edj.journals.ekb.eg/article_76455_461acec996678a3ef7b693285cfc2e0b.pdf
2017-10-01
3895
3905
10.21608/edj.2017.76455
Ahmad
Aboel-Fadl
1
Lecturer at Fixed Prosthodontics Dept. Ain Shams University. Lecturer at Fixed Prosthodontics Dept. Misr International University.
AUTHOR
Mostafa
el-Desoky
2
Demonstrator at Fixed Prosthodontics Dept. Badr University.
AUTHOR
ORIGINAL_ARTICLE
EVALUATION OF ZIRCONIA-REINFORCED LITHIUM SILICATE CERAMIC SURFACE TREATMENT ON THEIR SHEAR BOND STRENGTH TO DENTINE FOLLOWING IMMEDIATE DENTIN SEALING
Objectives: The purpose of this study was to evaluate zirconia-reinforced lithium silicate ceramic surface treatment on their shear bond strength to dentine following immediate dentin sealing.Methods : One hundred sixty extracted molars were initially divided into two main groups each counting eighty molars: based on dentine sealing protocols (without immediate dentin sealing S- and with immediate dentin sealing S+), those groups were further subdivided into four subgroups each counting twenty based on the ceramic surface treatment protocol. Each were further subdivided into two subdivisions to evaluate the bonding durability after thermodynamic aging process each counting ten specimens. All restorations were adhesively bonded using a light curing resin cement. The thermo-mechanical group were subjected to 10,000 thermal cycles between (5-55ºC) with a 30-s dwell time, 20 seconds transfer time. specimens were then subjected to maximum vertical load of 10 kg with cyclic frequency of 1.7 Hz for 240,000 cycles, which corresponds to one year of clinical service. Specimens were tested for shear bond strength using Instron testing machine. Data were statistically analyzed using two-way ANOVA and Tukey’s post-hoc tests.Result: A significantly higher shear bond strength of restorations (p ≤ 0.001) was obtained when immediate dentin sealing was followed regardless of the surface treatments of ceramics with a maximum value of 10.50±0.412 MPa. Both ceramic surface treatment and artificial aging had a statistically significant effect on the shear bond strength.Conclusion: Immediate dentin sealing protocol is recommended and HF surface treatment is recommended for ceramic restorations adhesion to achieve better durability.
https://edj.journals.ekb.eg/article_76456_95e456a5943f3a8b9fb320191acff2a3.pdf
2017-10-01
3907
3913
10.21608/edj.2017.76456
Immediate dentine sealing
Hydrofluoric acid
Cojet system
Thermodynamic stressing
Mahmoud
Shakal
1
Assistant Professor of Fixed Prosthodontics, Department of Fixed Prosthodontics, Faculty of Dentistry University of Tanta, Egypt
AUTHOR
ORIGINAL_ARTICLE
SHEAR BOND STRENGTH AND FAILURE PATTERN OF TWO SELF-ADHESIVE RESIN CEMENTS TO HYBRID CERAMIC UNDER DIFFERENT MODES OF POLYMERIZATION
Abstract: The purpose of this study was to evaluate the shear bond strength of two self-adhesive cements with different polymerization modes. cemented to a Hybrid-Ceramic CAD/CAM blocks (VITA ENAMIC® for CEREC®/ inLab®, VITA Zahnfabrik H. Rauter GmbH & Co.KG., Germany), Methods: Two self-adhesive resin cements: Rely X U200 (RX, 3M ESPE,St. Paul, MN, USA) and G-CEM Link ACE (GC, GC corporation, Tokyo, Japan). RX and GC groups with different polymerization modes (photo-curing (P) and self-curing (S)), were used in this study on hyprid ceramic Vita Enamic CAD/CAM blocks. Shear bond strength (SBS) tests were performed on all the specimens.Results: The highest SBS was recorded with RX S group whilst the lowest SBS values were recorded with the GC S groups. Based on Tukey’s post hoc significance analysis test, significance differences were observed between the RX S group compared to the GC S group (p < 0.05). No significance differences were found between data obtained from different curing modes of neither, RX S and RX P nor GC S and GC P. Adhesive pattern of failure was predominantly for most of the groups except RX S that was presented as predominant cohesive form of failure with the CAD/CAM hybrid ceramic block.Conclusion: Within the limitations of this in vitro study, polymerization modes had no significance, but more mixed failure patterns were observed when using the photo-curing mode than when using the self-curing mode.
https://edj.journals.ekb.eg/article_76457_e11f61d83d1a7d68b9625f688c641d2e.pdf
2017-10-01
3915
3921
10.21608/edj.2017.76457
self-adhesive resin cement
polymerization mode
failure mode, hybrid ceramic
Mahmoud
Shakal
1
Assistant Professor of Fixed Prosthodontics, Department of Fixed Prosthodontics, Faculty of Dentistry, University of Tanta, Egypt
AUTHOR
ORIGINAL_ARTICLE
CLINICAL PERFORMANCE OF ENDOCROWNS VS GLASS FIBER POST IN RESTORING ENDODONTICALLY TREATED FIRST PERMANENT MOLAR IN CHILDREN; A RANDOMIZED CONTROLLED TRIAL WITH 1 YEAR FOLLOW-UP
Purpose: to compare the clinical performance of endocrowns versus the fiber posts with composite cores used in restoring endodontically treated 1st permanent molar in children using FDI criteria.Materials& Methods: A single blind and parallel group study carried on 28 patients in the age group 10–13 years visiting endodontic clinic at MSA University seeking endodontic treatment of their decayed 1st lower molars. One week after completing endodontic treatment, patients were randomly divided into 2 groups: Group A (n=14): received lithium disilicate (IPS. emax-press) endocrowns & Group B (n=14): received glass fiber post with composite core. A clinical evaluation of debonding, fracture, caries and patient satisfaction was performed by a single examiner. Each was scored from 1 to 5 according to FDI where; 1 was clinically very good, and 5 was a clinically poor restoration that must be replaced. Patients were evaluated and recalled regularly at 3, 6, 9 and 12 months. Results: Regarding the restoration debonding and fracture; group A(endocrowns) showed 100% survival throughout all periods of follow up while group B (glass fiber posts with composite cores) showed decrease in survival rate over time. As for evaluation of caries and patient satisfaction; both groups were not statistically significant different.Conclusion: Endocrowns can be considered a clinically successful restoration for endodontically treated teeth in general and the concept can be adapted to the endodontically treated teeth in children.Clinical significant: Although more studies with increased sample size and long term follow-up are still required, endocrowns can be a permanent restorative option for endodontically treated 1st permanent molar in young age with a high success rates.
https://edj.journals.ekb.eg/article_76458_22f20b18955516de523240753d4a8ae4.pdf
2017-10-01
3923
3931
10.21608/edj.2017.76458
Endocrowns
glass fiber post
composite restoration
ETT young permanent molar
cuspal coverage
randomized clinical trials
FDI criteria
Aliaa
Mahrous
1
Lecturer Fixed Prosthodontic Department, Faculty of Dentistry, Fayoum University, Egypt.
AUTHOR
Naglaa
Ezz El-Din
2
Lecturer Pediatric and Community Dentistry Department, Faculty of Dentistry, Modern Science and Arts University, Egypt.
AUTHOR
Hinar
Al Moghazy
3
Lecturer Endodontic Department, Faculty of Dentistry, Modern Science and Arts University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF HUMAN ENAMEL ON WEAR OF THREE TYPES OF INTERIM RESTORATIVE MATERIALS (AN IN-VITRO STUDY)
Objectives: The purpose of the present study was to determine wear behavior of two different composite resin; UDMA / Urethane Dimethacrylate and bis-GMA based, compared with a PMMA conventional resin interim restorative materials. Materials and Methods: Thirty samples (10 of each material; Revotek LC, TempSpan, Jet tooth shade) were prepared in the form of discs (10 mm diameter and 2 mm thickness), then all samples were subjected to Two-body wear simulation test using a programmable logic controlled equipment. Human enamel was used in this study as specimen’s antagonist. Two wear measurement protocols; 1- roughness change measurement using the optical profilometry and, 2- weight loss measurement by electronic analytical balance were performed before and after loading Results: Roughness change comparison between the experimental material groups showed that the highest roughness change was recorded for Revotek-LC group mean value (-0.000539 ±0.003 µm) followed by Jet tooth shade group mean value (-0.000478 ±0.001 µm) while the lowest roughness change was recorded for TempSpan group mean value (-0.0002 ±0.001 µm). The difference between groups was statistically non-significant. On the other hand, weight change results showed that the highest weight change was recorded for Jet tooth shade group mean value (-0.006717 ±0.0006 gr) followed by Revotek-LC group mean value (-0.00345 ±0.0021 gr) while the lowest weight change was recorded for TempSpan group mean value (-0.001167 ±0.0004 gr), and the difference between groups was statistically significant as indicated by ANOVA test followed by Tukey’s post-hoc test (p=<0.0001<0.05) as indicated by ANOVA test followed by Tukey’s post-hoc test (p=0.9823>0.05). Conclusions: 1. There was no significant change in roughness of each tested interim restorative material before and after 3 months wear simulation cycles. 2. TempSpan and Revotek LC showed the highest wear resistance based on weight change measurements. 3. Jet tooth shade interim restorative material exhibit the lowest roughness change of enamel antagonist.
https://edj.journals.ekb.eg/article_76459_b17c934c9ed60c32ed73e0784bfa758b.pdf
2017-10-01
3933
3945
10.21608/edj.2017.76459
composite resin
Acrylic resin
Interim restorations wear
hardness
Khaled
Haggag
1
Assistant Professor, Crowns and Bridges Department, Faculty of Dental Medicine, Al Azhar University, Egypt
AUTHOR
Muhammad
Abbas
2
Assistant Professor, Dental Biomaterials Department, Faculty of Dental medicine, Al-Azhar University, Egypt
AUTHOR
Zainab
EL Sharkawy
3
Lecturer, Crowns and Bridges Department, Faculty of Dental Medicine for Girls, Al Azhar University, Egypt
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF FINISH LINE DESIGN AND THERMO-MECHANICAL AGING ON THE FRACTURE RESISTANCE OF TWO TYPES OF MONOLITHIC ZIRCONIA CROWNS
Objectives: The purpose of this study was to compare the fracture resistance of two types of CAD/CAM monolithic zirconia crowns with two finish line designs after thermo-mechanical aging. Materials and methods: A total of 40 zirconia crowns were milled and divided into two groups Bruxzir and Prettau zirconia (n=20). Each type of zirconia crowns was divided into two groups according to the finish line design, chisel (CH) and deep chamfer (DC) groups (n=10) After cementation of crowns to their corresponding dies, half of each group was subjected to thermo-mechanical aging, then fracture resistance was measured. Results: Statistical analysis showed the highest fracture resistance mean±SD value was recorded with Bruxzir non-aged CH group (3432.22±462.4), while the lowest fracture resistance mean±SD values was recorded with Prettau aged DC group (2658.97±417.2) as indicated by three-way ANOVA test (F= 11.8806, p= 0.0087<0.05).Conclusion: Within the limitations of this study, fully contoured zirconia crowns showed high resistance to failures and a minimally invasive preparation design should be determined as the optimal choice.
https://edj.journals.ekb.eg/article_76461_e5f52508efa9df9386cb2975f7b787b9.pdf
2017-10-01
3947
3953
10.21608/edj.2017.76461
Khaled
Haggag
1
Assistant Professor, Crowns and Bridges Department, Faculty of Dental Medicine, Al Azhar University, Egypt
AUTHOR
Mohammed
Hosny
2
Assistant Professor, Crowns and Bridges Department, Faculty of Dental Medicine, Al Azhar University, Egypt
AUTHOR
Muhammad
Abbas
3
Assistant Professor, Dental Biomaterials Department, Faculty of Dental medicine, Al-Azhar University, Egypt
AUTHOR
Hussein
Ramadan
4
Lecturer, Crowns and Bridges Department, Faculty of Dental Medicine, Al Azhar University, Egypt
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF DIFFERENT GAMMA RADIATION DOSES ON THE MECHANICAL PROPERTIES OF ESTHETIC RESTORATIONS
This in-vitro study investigated effect of different gamma radiation doses on the mechanical properties of esthetic restorations. A total of 84 standardized specimens were prepared for this study. Each 21 of them were prepared using the following four resin composites: Ceram X (Dentsply), Z350 xt (3M ESPE), Xtra fill (Voco) and Grandio (Voco). Then, the 21 specimens were divided as follows: 3 specimens representing the control group (C) were cured using wood pecker LED light cure unit, 9 specimens were subjected to gamma radiation after curing (IaC) from which three were subjected with a dose of 10 Gy (IaC-10), the other three with 30Gy (IaC-30) and the last three with 60 Gy (IaC-60); the last 9 specimens were subjected to gamma radiation before curing (IbC) from which three were subjected with a dose of 10 Gy (IbC-10), the other three with 30Gy (IbC-30) and the last three with 60 Gy (IbC-60). All specimens were subjected to measurement of surface microhardness in Vickers hardness tester. The depth of cure was calculated by obtaining the microhardness ratio through dividing VHN of the bottom surface by VHN of the top surface. Data was then recorded, tabulated and statistically analyzed. Most results of the specimens’ top showed statistically significant increase in mean microhardness of IaC and IbC sub-groups in relevance to the control groups. Most results of the specimens’ top showed statistically significant increase in mean microhardness of IbC sub-group in relevance to IaC sub-group. Results of (B/T) showed increase in mean depth of cure of IbC sub-groups in relevance to the control group and to IaC sub-groups, where most of them are statistically significant. Pearson correlation coefficient between top and bottom was found to be statistically significant (r = 0.9). In conclusion, surface microhardness of different composite resin have improved following being subjected to gamma radiation by various doses, on the other hand most of the results of the depth of cure was low for the group IaC and has improved for the group IbC.
https://edj.journals.ekb.eg/article_76462_97777579a3f8fb8196763998879f880f.pdf
2017-10-01
3955
3964
10.21608/edj.2017.76462
Ahmed
Aziz
1
Lecturer of Conservative Dentistry, Faculty of Dentistry, Egyptian Russian University, Cairo, Egypt
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF DIFFERENT ABUTMENT FINISH LINE CONFIGURATION ON STRESS DISTRIBUTION OF IMPLANT SUPPORTED ZIRCONIA FIXED PARTIAL DENTURE
Purpose: to study the influence of different abutment finish line configuration on stress distribution of implant supported fixed partial denture.Materials& Methods: Two endo-osseous screw vent implants for 2nd premolar and 2nd molar were chosen and placed parallel to each other. After resin model construction, Implants were attached to the corresponding abutments group according to the finish line configuration of the abutments. Group A: standard abutment with circular contour, Group B: anatomical abutment with anatomical contour. The fixed partial denture was designed with a flat area on the occlusal surface to accommodate for the loading pin tip each time. Strain gauges were adhered to four different sites (buccal, lingual, mesial and distal) and a force of 200N over 30 seconds duration and maintained for 30 seconds also. Then forces were removed and residual strains were released for 2 minutes.Results: One-way ANOVA used to compare between different abutment finish line configuration and teeth for mean Strain (µm/m) and total strain followed by Tukey’s post-hoc test for pairwise comparison. Significant level set at p < 0.05.The results revealed that all types of abutments have a certain level of misfit, which resulted in measurable strains. Significant difference was found between the different groups of the finish line configuration (standard & anatomical).Conclusion: Difference in abutment finish line configuration may affect the stress pattern induced around dental implants. Clinical significant: implant abutment with anatomical finish line configuration is a preferred selection for better stress distribution.
https://edj.journals.ekb.eg/article_76463_c18198a4e23d65a7b67b8e801b311cf0.pdf
2017-10-01
3965
3972
10.21608/edj.2017.76463
anatomical abutment finish line
circular abutment finish line
Stress analysis
misfit
Aliaa
Mahrous
1
Lecturer Fixed Prosthodontic Department, Faculty of Dentistry, Fayoum University, Egypt.
AUTHOR
ORIGINAL_ARTICLE
THE EFFECT OF USING ANTIFUNGAL GEL ON RETENTIVE BOND STRENGTH OF TWO FORMS OF DENTURE ADHESIVES AN IN VITRO STUDY
Purpose of this in vitro study is Recognition the effect of using of the miconazole gel opposing two forms of improving denture retention materials (Zinc-free Polygrip cream and Snug denture soft cushion) on their retention strength.Materials and method: Eight heat cured acrylic samples were prepared having equal dimension flat tested surface. Two well adapted tested surfaces were matched and fixed to universal testing machine clamp. Vertical separating load was applied in a rate of 1mm/min to measure maximum load before failure of denture adhesive. These measurements were used to express the retention strength when improving denture material was used alone or opposed by miconazole nitrate gel.Result and Conclusion: The mean difference of tensile strength showed significant reduction when antifungal gel opposed the two denture adhesive forms. Snug denture cushion showed higher retention strength when used alone or opposed by miconazole gel when compared with zinc-free Polygrip cream.
https://edj.journals.ekb.eg/article_76464_1ffe2a812222f09b020071eff1b2bfaf.pdf
2017-10-01
3973
3981
10.21608/edj.2017.76464
Denture adhesive-antifungal miconazole nitrate
denture retention strength
Khaled
Amin
1
Associate Professor, Oral and Maxillofacial Prosthodontics Department, Faculty of Dentistry, King Abdulaziz University.
AUTHOR
Abdulelah
Binmahfooz
2
Associate Professor, Oral and Maxillofacial Prosthodontics Department, Faculty of Dentistry, King Abdulaziz University.
AUTHOR