The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
EVALUATION OF ACETAL RESIN AND COBALT–CHROMIUM CLASP DEFORMATION AND FATIGUE RESISTANCE IN REMOVABLE PARTIAL DENTURE CLASPS AN IN-VITRO STUDY
2459
2464
EN
Mohamed
Ahmed M.
Helal
Professor of Removable Prosthodontics, Faculty of Dental Medicine, Al-Azhar University. Boys Branch, Cairo, Egypt
Ibrahem
Ali
Abd El Rahman
Dentist at the MOH, El-Mansoura, Egypt
Hassan
Mohamed
Sakar
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine, Al-Azhar University. Boys Branch, Cairo, Egypt.
Amr
Salah El-Din Abd Elshafy
Gomaa
Lecturerof Removable Prosthodontics, Faculty of Dentistry, Al-Fayoum University, Fayoum, Egypt.
Mohamed
Abbas
Assistant Professor of Dental Material, Faculty of Dental Medicine, Al-Azhar University. Boys Branch, Cairo, Egypt
10.21608/edj.2017.76062
Purpose: this study was aimed to evaluate the fatigue resistance (amount of clasp deformation) of acetal resin clasps and Cobalt-Chrome (Co-Cr) clasps after attachment/detachment cycles on abutment teeth with two different undercuts. <br />Materials and Method: Twenty models were constructed by placing either an upper 1st premolar or upper 1st molar inside an acrylic rectangular block. Models were divided according to the abutment teeth into two groups (GI for 1st premolars group and GII for 1st molars group), 10 each. Each group was divided into two subgroups according the framework material, SGA for acetal resin clasp and SGC for Co-Cr clasp. Each testing models and its framework were mounted inside universal testing machine (Lloyd instruments Ltd, England). Cycling was carried out for each specimen till 2920 cycles. The data of the amount of clasp deformation after cycling were collected and tabulated. The data were subjected to statistical analysis using student’s t and paired t tests. <br />Results: After 2920 cycles, the mean values and standard deviations of the clasp deformation for SGIC, SGIA, SGIIC and SGIIA were 0.0532±0.006, 0.007±0.003, 0.04323±0.0048 and 0.0275±0.004 mm, respectively. <br />Conclusions: Co-Cr clasps had significant clasp deformation more than acetal resin clasps. Increase the thickness of cross section of the acetal resin clasp more than 1 mm was recommended in case of engaging undercut more than 0.25 mm.
https://edj.journals.ekb.eg/article_76062.html
https://edj.journals.ekb.eg/article_76062_3a33a93f9d067de8abf16994fc97d7b1.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
CYTOTOXICITY OF NOVEL SODIUM HYPOCHLORITE BASED INTRA CANAL MEDICAMENT
2465
2470
EN
Ahmed
Mostafa
Ghobashy
Lecturer of Endodontics, Department of Endodontics, Faculty of Dentistry, Misr International University,
Cairo Egypt
Amr
Bayoumy
Lecturer of Endodontics, Department of Endodontics, Faculty of Dentistry, Misr International University,
Cairo Egypt
10.21608/edj.2017.76063
Aim: The aim of this study was to compare the cytotoxicity of triple antibiotic paste, calcium hydroxide and sodium hypochlorite gel when used as intra-canal medicaments on cultured fibroblasts.<br />Methodology: Experimental groups were divided into three groups; Group (CaOH), Group (TAP) & Group (NaOCl). Cytotoxicity of tested materials was determined by the microculture tetrazolium (MTT) assay. Optical density representing the residual living cells was determined for each group at different concentrations at 2h, 4h, 24h and 48h. Data were then collected, tabulated and statistically analyzed<br />Results: Statistical analysis showed that the duration range from 2 hours up to 48 hours has no significant effect for each of the three tested medicaments. There was no significant difference between CaOH and NaOCl groups wheareas TAP group recorded significantly lower viability results.<br />Conclusion: Under the condition of the current study, NaOCl gel is considered acceptable intracanal medicament regarding cytotoxicity in comparison to CaOH and Triple antibiotic paste.
https://edj.journals.ekb.eg/article_76063.html
https://edj.journals.ekb.eg/article_76063_5bb7d270c473c7a593f822192512623c.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
IMPACT OF CPP-ACPF AND SODIUM FLUORIDE REMINERALIZING PASTS ON SURFACE TEXTURE OF RESIN COMPOSITES
2471
2486
EN
Nabawy
A.
Alrobeigy
Assistant Professor, Department of Dental Biomaterials, Faculty of Dentistry, Tanta University, Egypt
Yasser
A.
Abed
Assistant Professor, Department of Operative Dentistry, Faculty of Dentistry, October 6 University, Egypt
10.21608/edj.2017.76064
Purpose: To investigate and compare the impact of casin phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) and sodium fluoride, remineralizing pasts, on surface texture of four different resin composites. <br />Methods: 20 disc specimens (5 mm × 2 mm) were prepared from each of four resin composites that belong to the categories of conventional (Filtek Z250 XT; F250), flowable (Filtek Z350 XT; F350), high viscosity bulk-fill (Filtek Bulk Fill Restorative Posterior; FBF), and self-adhering flowable (Vertise Flow; VF). After polishing, the specimens of each material were divided into four groups (n=5): group 1: without treatment, dry-stored; group 2: without treatment, water-stored; group 3: treated with GC Tooth Mousse Plus (TMP) 15 min/once daily and stored in distilled water; and group 4: treated with Clinpro White Varnish (CWV) 15 min/once daily and stored in distilled water. All specimens were stored for 15 days at 37οC. The surface roughness was determined using non-contact 3D Optical Profiler. Three exposures were performed on top surface of each specimen. Statistical analysis was performed using ANOVA followed by Tukey HDS. <br />Results: For all materials investigated; the roughness values of TMP-treated group were not affected (P > 0.05) compared to control group, while they were significantly (P < 0.001) reduced compared to water-stored, except for VF. However, the roughness values of CWV-treated group were significantly (P < 0.001) increased compared to both control and water-stored groups, for all materials. The values of all roughness parameters of TMP-treated group of each composite tested were significantly (P < 0.001) lower than those of CWV-treated group, except for Sp and Sv parameters regarding VF. <br />Conclusions: TMP produced a significant surface smoothening of nano-composites used in this study, while CWV caused a significant increase in roughness values of all materials. Topical application of TMP could be used clinically without adverse effects on surface texture of resin composites.
CCP-ACP,Sodium fluoride,Surface roughness,resin composites
https://edj.journals.ekb.eg/article_76064.html
https://edj.journals.ekb.eg/article_76064_7240cc174f016ae0c13fcce14690c679.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
EFFECT OF SURFACE TREATMENT AND ARTIFICIAL AGING ON MICROTENSILE BOND STRENGTH OF ZIRCONIA TO RESIN CEMENT
2487
2494
EN
Ahmed
M.
Hamdy
Associate Professor, Fixed Prosthodontic Department, Faculty of Dentistry, MSA University
Abou Bakr
Hossam
Hashem
Lecturer, Research Institute of Ophthalmology, Dental Department
10.21608/edj.2017.76065
Statement of problem: Reliable bond to zirconia based materials has proven to be difficult which is the major limitation against luting zirconia restorations.<br />Purpose: This in vitro study compared effect of selective infiltration etching (SIE) and tribo-chemical silica sandblasting (TSS) on microtensile bond strength to zirconia based material before and after different artificial aging intervals. <br />Materials and methods: Twenty Lava plus high translucency zirconia disks (3 M, ESPE) were randomly divided into two study groups according to their surface treatment: (a) selective infiltration etching (SIE) and (b) tribo-chemical silica sandblasting (TSS). Zirconia disks were bonded to composite resin specimens using Panavia F2.0 resin cement. Zirconia resin bond strength was evaluated using the microtensile bond strength test (MTBS) and the test was repeated before and after the following intervals of accelerated artificial aging; 1 week, 2 weeks, 3 weeks and 4 weeks of water storage (37°C). A repeated measures ANOVA and Bonferroni post-hoc tests were used to analyze the data.<br />Results: The interaction between surface treatments and storage times were statistically significant. Data analysis revealed significant differences between the two surface treatments (P<0.05).Selective infiltration etched specimens demonstrated relatively higher MTBS values than TSS (48.5 and 24.8 MPa).SEM examination of broken microbars revealed more interfacial failure type for TSS than SIE specimens that showed a predominantly cohesive failure type. <br />Conclusions: Selective infiltration etching provided superior micro-tensile bond strength results compared to tribo-chemical silica sandblasting. Established bond strength by selective infiltration etching was not affected by artificial aging as tribo-chemical silica sandblasting.
https://edj.journals.ekb.eg/article_76065.html
https://edj.journals.ekb.eg/article_76065_014ddf06ff201857a27d292fc9dc81b3.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
THE EFFECT OF AGING ON MICROSHEAR BOND STRENGTH OF RESIN CEMENT TO MONOLITHIC ZIRCONIA
2495
2505
EN
Maged
M. Mohamed
Zohdy
Lecturer at Fixed Prosthodontics Dept. Ain Shams University. Lecturer at Fixed Prosthodontics Dept. British
University in Egypt.
Ahmad
Khaled
Abo El Fadl
Lecturer at Fixed Prosthodontics Dept. Ain Shams University. Lecturer at Fixed Prosthodontics Dept. Misr
International University.
10.21608/edj.2017.76068
Purpose. Successful long-term bonding to zirconia ceramic remains a challenge, requiring special cements and treatments, which might negatively affect the ceramic. <br />The purpose of this study was to evaluate the durability of micro-shear bond strength between resin cement containing phosphate monomer and zirconia ceramic submitted to different surface treatments before and after aging.<br />Material and methods monolithic zirconia (Bruxzir Glidewell, California, USA) was selected as the substrate material. The ceramic surfaces, were either left untreated as-sintered (Group NT), silica coated with Rocatec soft system (3M/ESPE, USA) (Group CT), or treated with Alloy Primer (Kurary, Japan) (Group PR). They were bonded with a dual-cured resin cement; Panavia v5 (Kurary), using an adhesive system (Clearfil SE Bond). A micro-shear bond test was carried out to measure the bond strength of the resin cement to the zirconia surface. Samples were tested in a universal testing machine at a crosshead speed of 0.5 mm/minute before and after 90 days of water storage and 6000 thermal cycles (dwell time, 30 seconds). Statistical analysis was performed using a two-way ANOVA model, at pResults. Mean microshear bond strength ranged from 14.39 to 21.59 MPa after 3 days and from 5.64 to 20.42 MPa after aging. Water storage and thermal cycling decreased bond strength significantly for NT and PR groups, while it had no significant effect on CT group. Early bond strength was highest with CT and PR groups with no significant difference between them, and they were both statistically significantly higher than NT group. SEM analysis showed an increase in interfacial adhesive failure after aging.<br />Conclusions. Within the limitations of this study, it was concluded that silica coating and application of a chemical primer produced higher bond strengths to resin cement than leaving zirconia untreated. Aging significantly reduced the bond strengths for the untreated and primed zirconia, while silica coated zirconia remained stable and was not affected.
https://edj.journals.ekb.eg/article_76068.html
https://edj.journals.ekb.eg/article_76068_b4017f0cf5a2b75083998623b2acece1.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
SMILE ANALYSIS AND ESTHETIC PERCEPTION OF A SAMPLE OF SAUDI POPULATION
2507
2513
EN
Kholood
Alhussami
Intern, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
Hani
M.
Nassar
Assistant professor, Department of Restorative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah,
Saudi Arabia.
10.21608/edj.2017.76069
Aim: The aim of this observational study was to assess the different esthetic smile criteria of adults in Saudi Arabia. Further goals were to find the predominant dental shades and assess subjects’ esthetic perception in a sample of Saudi community.<br />Materials and Methods: Thirty subjects were recruited from King Abdulaziz University Dental Hospital in Jeddah, Saudi Arabia. Subjects were between 18-50 years of age with intact upper anterior teeth and healthy gingiva. All participants were photographed and the following smile parameters were recorded: tooth geometry, shade, midlines, smile arc, and upper lip position. Parameters were plugged in a dedicated smile analysis software and the golden proportion values were obtained. Data were analyzed using Chi Square and Student’s t-tests according to variables tested at 0.05 significance level.<br />Results: Regardless of age and sex, 70% of the sample has an average lip position, and consonant smile arc was the prevalent form among 73.3% of the sample. The most common shade was A2 regardless of tooth type or position. Almost half of the participants were satisfied with their overall appearance and only 6 subjects were not satisfied with the size of their teeth. Overall, the golden proportion was not present in the tested sample. <br />Conclusion: Despite the absence of golden proportion, the majority of the sample tested was satisfied with their smile parameters. The prevalent shade was A2 in both genders.
Smile analysis,Esthetic perception,shade,and golden proportion
https://edj.journals.ekb.eg/article_76069.html
https://edj.journals.ekb.eg/article_76069_b44dc87a2f47681d4122549e76da68b4.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
COMPARISON BETWEEN SINGLE IMPLANT AND TWO IMPLANTS WITH LOCATOR ATTACHMENT RETAINING MANDIBULAR OVERDENTURE (IN VITRO STUDY)
2515
2523
EN
Hebatallah
Tarek M.
Abdallah
Lecturer of Prosthodontics, Faculty of Dentistry, Ain Shams University
10.21608/edj.2017.76072
In vitro study was done to compare between single implant and two implants with locator attachment and their effect on the implants and supporting structure. Two mandibular acrylic models were made with placement of one implant at the midline and placement of two implants in the canine region both with locator attachment .Each implant was 3.8 mm in diameter and 12 mm in length. Channels were done in each model mesial and distal to the implants to receive the strain gauge. Each attachment was fitted to its overdenture .The acrylic model was placed on the lower flat metal plate of the testing machine. A loading device (universal-testing machine) was used to apply standardized static load. Loads were applied with magnitude of 100N. A special load applicator was used to apply standardized static load. Loading performed unilaterally in vertical direction at right 1st molar on both model. Comparing the results of single implant and two implants with locator attachment and their effect on the implants showed no significant difference between them (p value>0.05). So it can be concluded that post loading implant survival of single implant overdenture is not significantly different from two implants overdenture with locator attachement.
https://edj.journals.ekb.eg/article_76072.html
https://edj.journals.ekb.eg/article_76072_1e65ba8073553aaf235847f98231ad33.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
RETENTION AND CHEWING EFFICIENCY OF TWO DIFFERENT DISTRIBUTIONS OF FOUR MINI-DENTAL IMPLANT IN MANDIBULAR IMPLANT RETAINED OVERDENTURES
2525
2534
EN
Hala
Mohamed
Abd El Hameed
Assistant Professor of Prosthodontics, Faculty of Dentistry, Suez Canal University
Khaled
Omran
Sultan
Assistant Professor of Prosthodontics, Faculty of Dentistry, Suez Canal University
10.21608/edj.2017.76073
Purpose: The purpose of this research was to study the effect of two different distribution of four mini-dental implant retaining mandibular overdenture on it’s retention and patient chewing efficiency.<br />Materials and methods: Twelve completely edentulous male patients were selected from department of Prosthodontics, Faculty of Dentistry; Suez Canal University. Patients received maxillary complete dentures opposing implant retained mandibular overdentures with four mini dental implant .The patients were randomly classified into two equal groups according to mini dental implant’s distribution. Group I : in which patients received four mini dental implants placed equally in the intrforaminal region. GroupΙΙ : in which patients received four mini dental implants, in the canine and the first molar regions in each side of the arch Clinical evaluation A-Mandibular overdenture retention . A- digital forcemeter device was used to measure mandibular overdenture retention. B- Chewing efficiency (Masticatory performance) Six chewing efficiency records were made for each patient as follows: 3 times periods at (one, two & three) months for the two types of (hard& soft) food The data obtained were reported in the form of mean values of both the chewing times and number of chewing strokes. Then chewing velocity (stroke/sec) were calculated. These data were recorded and statistically analyzed. <br />Results: The results of this study showed that there was increase in mean values of chewing efficiency of hard and soft food for both groups in favor to group II with non statistical significant difference between both groups except after three months in masticatory performance. Also there was increase in mean values of mandibular overdenture retention for both groups in favor to group II with highly statistical significant difference during all observation periods at (p≤0.01).<br />Conclusion: Within the limitations of this study, it may be concluded that wide distribution of immediately loaded mini-dental implants used in mandibular overdentures through posterior placement beyond the interforaminal area results in favorable response in terms of increased denture retention. This positively reflected on the patient comfort with increased his self confidence and psychological acceptance consequently, improves oral function and chewing efficiency.
https://edj.journals.ekb.eg/article_76073.html
https://edj.journals.ekb.eg/article_76073_b4ac86256951ef867df23b9db8de68e4.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
WEAR PERFORMANCE OF NANO-COMPOSITE ARTIFICIAL DENTURE TEETH
2535
2544
EN
Muhammad
Abbas
Assistant Professor, Dental Biomaterials Department, Faculty of Dental medicine, Al-Azhar University, Egypt
Hassan
Sakr
Assistant Professor, Removable Prosthodontics Department, Faculty of Dental medicine, Al-Azhar University,
Egypt
10.21608/edj.2017.76074
Statement of Problem: Civilizing the wear resistance of artificial denture teeth is of importance to prosthodontic patients, as wear may affect the denture esthetics and functions. To counteract this problem, artificial teeth with increased wear resistance had been introduced in the market. <br />Aim: The aim of the current study was to compare the amount of wear between nanocomposite and acrylic (PMMA) artificial teeth.<br />Materials and methods: Ten teeth were fabricated (reproduced) from nanocomposite (Z350) by duplicating one tooth from the ready-made conventional acrylic artificial teeth. Fifteen artificial teeth were chosen from ready-made acrylic resin teeth. Mandibular 1st molars were only chosen for testing. The 2-body wear testing was performed using multi-modal ROBOTA chewing simulator. Test samples were mounted against 600 grit sandpaper and tested under a load of 700 gram for 10,000 cycles of rotation. Height and weight were measured before and after wear test for each specimen to determine the loss in both. Qualitative analysis of the wear areas was completed using USB Digital microscope with a built-in camera connected with an IBM compatible personal computer using a fixed magnification of 25X. Results: It was found that Nano-composite group recorded higher height loss mean value than conventional group height loss mean value. The difference between both groups was statistically non-significant (p>0.05) as indicated by unpaired t-test. Also Nano-composite group recorded higher weight loss mean value than conventional group weight loss mean value. The difference between both groups was statistically non-significant (p>0.05) as indicated by unpaired t-test.<br />Conclusions: Nano-composite teeth exhibited non-significant higher wear than conventional artificial acrylic teeth.
Wear- Nanocomposite teeth- Acrylic teeth
https://edj.journals.ekb.eg/article_76074.html
https://edj.journals.ekb.eg/article_76074_93ae4b6fc794d70ed88cba69ac592b19.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
THE EFFECT OF TWO MANDIBULAR CLASS I REMOVABLE PARTIAL DENTURE DESIGNS ON THE PERIODONTAL HEALTH OF THE ABUTMENT TEETH: A RANDOMIZED SPLIT-MOUTH CLINICAL TRIAL
2545
2554
EN
Khaled
Kamal Eldin
Amin
Ass. Prof. Removable Prosthodontics, Faculty of Dentistry, King Abdulaziz University Faculty of Dentistry,
NAHDA University-Beni Suef.
Osama
Mohamed
Gouda
Ass. Prof. Oral medicine, Periodontology, Diagnosis, Faculty of Dentistry, NUB (Nahda University in Beni Suef),
& Faculty of Dentistry, Suez Canal University, Ismailia, Egypt.
Naglaa
M.
Elwakeel
Ass. Prof. Oral Medicine, Periodontology, Diagnosis, Faculty of Dentistry, Al Azhar University (Girls Branch)
10.21608/edj.2017.76200
The aim of this study was to assess the effect of RPI direct retainer designs in mandibular Kennedy’s class I removable partial denture cases, on the periodontal conditions of their abutment teeth.<br />Materials and methods: A total of 10 systemically healthy Patients were selected with mandibular Kennedy class I with symmetrical healthy periodontium at first premolar abutments split mouth mandibular class I removable partial denture designs RPI, I-bar (Rest, proximal plate and I bar) in one side (side A) and a modified RPI clasp assembly (Rest, proximal plate connected by lingual bracing arm to the rest and I Bar) in other side (side B) were constructed. Clinical evaluation(gingival index, pocket depth and clinical attachment loss) and recording of GCF levels of Interlukin1ß IL1 –β using ELISA were carried out for all patients at base line (time of denture insertion), 3 months and 6 months after denture insertion at mandibular free end saddle abutments.<br />Results: A statistically significant increase in the mean IL-1ß levels after 3 months with further significant increase after 6 months was recorded in both sides (P ≤ 0.05) further, side B showed a statistically increased IL-β levels compared to side A. Regarding clinical parameters, side B showed a statistical significant increase at 6 months compared to side A regarding PD with no significant difference between the 2 sides at 3 months ,as for CAL and GI, although side B showed an increased readings in 6 months and 3 months compared to side A, a non significant difference was recorded between the 2 sides, as well, a non significant change in GI and CAL was recorded in both sides over the study period .<br />Conclusion: within the limitation of our study, the modified RPI clasp induced increasing of proinflammatory cytokines IL- 1ß levels in GCF compared conventional RPI clasp assembly. Both Clasp designs have an effect on periodontal health of free end saddle’s partial denture abutments.
RPI clasp, I-bar clasp designs,RPI modifications,IL- 1ß,mandibular Kennedy class I,periodontal health
https://edj.journals.ekb.eg/article_76200.html
https://edj.journals.ekb.eg/article_76200_ebaea090d8abe607e4511d0cbc43f37c.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
EFFECT OF MARGIN DESIGNS AND PORCELAIN VENEERING ON ACCURACY OF BI LAYERED ZIRCONIA CROWN
2555
2562
EN
Adel
A.
El Badawy
Assistant Professor of Crown and Bridge, Faculty of Dentistry, Al-Azhar University, Egypt
Mohammed
H.
Abd El-Aziz
Assistant Professor of Crown and Bridge, Faculty of Dentistry, Al-Azhar University, Egypt
Elsayed
A.
Omar
Assistant Professor of Crown and Bridge, Faculty of Dentistry, Al-Azhar University, Egypt
10.21608/edj.2017.76204
Statement of problem: Degree of marginal discrepancy determines effectively success and failure of fixed restorations.<br />Purpose: To evaluate the effect of porcelain veneering techniques on the marginal fit of bi- layered zirconia crown using four marginal designs.<br />Materials and Methods: A 40 Plaster replicas were made from two master dies and divided into two main groups (20 for each) according to type of finish line. Each group subdivided into two subgroups (10 for each) to obtain the following groups {A1} shoulder without cervical collar {A2} shoulder with 1 mm cervical collar. {B1} chamfer without cervical collar {B2} chamfer with 1 mm cervical collar. Zirconia blanks were milled using CAD/CAM system to produce 40 zirconia copings. Then, Veneering of the copings was done. Vertical gap distances were measured at 18 predetermined points. <br />Results: Veneering with porcelain exhibited statistical significant difference in mean values of marginal gap in both group {A1} and {B1}, while veneering with porcelain did not exhibit significant difference in both group {A2} and {B2} in comparison with the pre veneering state. Correlations based on the finish line design exhibited significant difference in mean values of marginal gap between all tested groups. Correlations based on presence or absence of cervical zirconia collar did not exhibited statistical significant difference between tested groups. On other hand, there were significant differences in mean values of marginal gap between tested groups in post veneering state, at the level of P value < 0.05. <br />Conclusions: Marginal fit of the final crowns with chamfer finish lines were better than that with shoulder, however, veneering with porcelain significantly raised marginal gap distance of crowns with collarless shoulder and chamfer preparations, while in that designs with cervical collar, veneering was not significantly affected on the marginal gap distance for both finish line designs
https://edj.journals.ekb.eg/article_76204.html
https://edj.journals.ekb.eg/article_76204_0146c750e0a419490900dc6c40190aa9.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
ANTIBACTERIAL EFFECT OF TWO BLEACHING AGENTS: IN VIVO STUDY
2563
2569
EN
Dalia
M
Abu-Elmagd
Professor, Department of Operative Dentistry, King Abdulaziz University, Faculty of Dentistry, Jeddah, Saudi
Arabia and Cairo University, Faculty of dentistry, Cairo, Egypt
Ahmed
Z
El-Hoshy
Associate Professor, Department of Operative Dentistry, Cairo University, Faculty of Dentistry, Cairo, Egypt
10.21608/edj.2017.76207
Objective: To investigate the antibacterial effect of two commercially available bleaching agents in vivo. <br />Materials and Methods: 30 volunteers were divided into 3 groups, a control group (chlorhexidine) and 2 treatment groups (Nite White ACP and Nite White ACP Turbo bleaching gels). Stimulated whole saliva samples were collected at baseline, after 1 and 3 applications and 14 days post-treatment. Total count of aerobic bacteria was determined. <br />Results: For all groups there was a statistically significant decrease in mean count of aerobic bacteria compared to baseline through all periods of the study. After 1 application and <br />3 applications, there was no statistically significant difference between mean percentage reductions in bacterial counts of the three groups. After 14 days, Nite White ACP Turbo showed the statistically significantly highest mean percentage reduction, followed by Nite White ACP group, then the control group. <br />Conclusion: Bleaching agents can reduce the total count of aerobic bacteria in saliva in vivo.
https://edj.journals.ekb.eg/article_76207.html
https://edj.journals.ekb.eg/article_76207_0d1b73d809c1bca4d9beb8882ac25895.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
COMPARATIVE STUDY BETWEEN THE EFFECT OF CLASS II AMALGAM AND COMPOSITE RESTORATIONS IN POSTERIOR TEETH ON PERIODONTAL TISSUES HEALTH
2571
2577
EN
Yasser
Al-Fawaz
Lecturer, Department of Restorative Dental Sciences, College of Dentistry, King Saud University.
Raneem
Alofi
Assistant professor, Department of Restorative Dental Sciences, College of Dentistry, King Saud University
Hafez
Diab
Professor of Periodontology, Riyadh Colleges of Dentistry and Pharmacy. and Faculty of Dentistry, Tanta University
10.21608/edj.2017.76208
Aim of the study: To investigate and compare the effect of class II amalgam and composite restorations on periodontal tissues health.<br /> Materials & Methods: The gingival index, plaque index, probing depth and clinical attachment level of one hundred teeth (50 restored by class II amalgam filling and 50 restored by class II composite filling) were included in the present study. One hundred teeth were classified into two groups as follows: Group I: involved 50 teeth restored by class II amalgam filling. Group II: involved 50 teeth restored by class II composite filling. The data was analyzed comparing both groups. The descriptive statistics included the mean, range and standard deviation for both groups.<br />Results: Our results showed that there is statistically significant decrease in GI, PPD and CAL scores of amalgam group compared to composite group. Whereas there is no statistically significant in PD scores between both groups<br />Conclusions: Class II composite restorations appear to be associated with periodontal breakdown more than class II amalgam restoration.
https://edj.journals.ekb.eg/article_76208.html
https://edj.journals.ekb.eg/article_76208_78878381e275553421ac7840b028c4ba.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
INFLUENCE OF THERMOCYCLING FOLLOWING APPLICATION OF FLUORIDE-RELEASING RESIN ON SHEAR BOND STRENGTH OF METAL BRACKETS
2579
2588
EN
Nabawy
A
Alrobeigy
Assistant Professor, Department of Dental Biomaterials, Faculty of Dentistry, Tanta University, Egypt
10.21608/edj.2017.76209
Objectives: To assess the influence of thermocycling following application of fluoride resin agent on shear bond strength (SBS) of metal orthodontic brackets bonded with two self-etching primers (SEPs). <br />Materials and methods: Eighty extracted upper premolars were randomly divided into 4 equal groups (n=20) and stainless steel brackets were bonded to their buccal surfaces as follows: group 1, teeth were conditioned with Transbond Plus SEP (3M Unitek, Monrovia, Calif), then brackets were bonded with Transbond XT adhesive (3M Unitek) and no fluoride resin applied; group 2, teeth were bonded as in group 1, and subsequently a fluoride-releasing resin (Ortho-Coat, Pulpdent, Watertown, Mass) was applied ; group 3 teeth were conditioned with Clearfil Protect Bond antimicrobial SEP (Kuraray Medical, Osaka, Japan), then brackets were bonded with Transbond XT adhesive and no fluoride resin applied; and in group 4, the same protocol for brackets bonding as in group 3 was used followed by an application of Ortho-Coat. All specimens were stored in distilled water (24 h., 37oC) then, half of each group (n=10) subjected to SBS debonding and the other half (n=10) were thermocycled before debonding. The adhesive remnant index (ARI) score was also recorded after debonding. The data of SBS and ARI scores were statistically analyzed by using 3-way ANOVA and Chi-Square test, respectively <br />Results: The application of Ortho-Coat had no significant effect on SBS values of both SEPs, either before or after thermocycling. SBS values of both SEPs were not significantly changed by thermocycling whether Ortho-Coat was applied or not. No significant difference was noted between the two SEPs in any application condition. No significant differences were found in the ARI scores. <br />Conclusions: The application of fluoride-releasing resin had no negative effect on SBS of metal brackets bonded with the two SEP systems. Thermocycling had no effect on SBS of the both SEPs either with or without fluoride-releasing resin application.
orthodontic brackets,bond strength,fluoride-releasing resin,self-etching primers,thermocycling
https://edj.journals.ekb.eg/article_76209.html
https://edj.journals.ekb.eg/article_76209_a5ae99aa97a20add1316ea2acd7aee75.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
RADIOGRAPHIC AND CLINICAL EVALUATION OF FIXED D TACHABLE PROSTHESES VERSUS TELESCOPIC OVERDENTURES SUPPORTED BY OSSEOINTEGRATED IMPLANTS
2589
2598
EN
Amr
Mohamed Ismail
Badr
Lectrurer of Removable Prosthodontics, Faculty of Dentistry, Minia University
Ahmed
Gamal Ahmed
Hassan
Lectrurer of Removable Prosthodontics, Faculty of Dentistry, Minia University
Ahmed
Shawkat Rateb
Hashem
**Lecturer of Oral Medicine and Periodontology, Faculty of Dentistry, Damanhour University
10.21608/edj.2017.76210
The purpose of the present study was to evaluate radiographically (the crestal bone level change) and clinically (gingival crevicular fluid and implant stability) in cases with four implants supporting mandibular fixed detachable prostheses versus telescopic overdenture.<br />Methodology: Twenty completely edentulous patients were treated with four interforaminal implants to support either fixed detachable prostheses with distal cantilevers or telescopic overdenture. The peri-implant marginal bone loss was assessed radiographically at distal surface of posterior implant bilaterally was calculated in two different intervals. The first interval (0-6months) and the second interval (0-12months) using a digital panoramic imaging system. Also clinical evaluation for checking the implant stability using the perio-test and measuring the gingival crevicular fluid.<br />Results: Regarding the gingival crevicular fluid, the comparison between both groups at the time of delivery and after 6 months, there was no significant difference between the two groups. But there was a significant difference after 12 months. From the obtained data of periotest, it was recognized that there was no significant difference between the two groups regarding the implant stability. But there was a significant difference within each group at the different follow-up periods. The data of marginal bone loss at the distal surface of posterior implant on both sides revealed that there was a significant difference between the two groups at the 1st and 2nd intervals.<br />Conclusion: Both telescopic overdenture and fixed detachable prostheses considered a viable successful treatment option for rehabilitating completely edentulous cases. Telescopic overdentures showed less crestal bone loss at the distal implants than that with the fixed detachable design. The gingival crevicular fluid decreases gradually throughout the study period in both designs denoting successful oral hygiene measurements.
https://edj.journals.ekb.eg/article_76210.html
https://edj.journals.ekb.eg/article_76210_698dcc2f4e3317a91487ab905aab93d9.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
MONITORING OCCLUSAL HARMONY/ DISHARMONY IN IMPLANT RETAINED RESTORATIONS USING DIGITAL OCCLUSAL ANALYZER
2599
2605
EN
Safa’a
A
Asal
Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Tanta Universty, Egypt
Moustafa
A
Hassaballa
Associate Professor, Department of Prosthodontics, Faculty of Dentistry, Pharos University, Egypt.
Abdulaziz
A
Alkheraif
Professor, Dental Technology Depart., College of Applied Medical Sciences, King Saud University
10.21608/edj.2017.76211
Since dental implants are not anchored to bone with periodontal ligament, subjective evaluation of occlusion is not always reliable enough to guard against the presence of occlusal prematurities. Despite the introduction of the T-scan occlusal analyzer technology, the majority of the clinicians and dental colleges are still depending, to a great extent, on the traditional occlusion indicator materials for implant-prosthetic occlusion establishment. This study was performed to verify whether the use of the articulating paper to calibrate the occlusal contacts of prosthetic restorations is successful enough to fulfill the objectives of a balancing implant-prosthetic occlusion. <br />Materials and Methods: 40 subjects [30 females and 10 males] were selected from the out patient clinic of the Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh. All subjects have received implant restorations where the occlusion of all cases was analyzed solely by the articulating paper. Computerized occlusal analysis was conducted using the T-Scan system III (software version 8.1). Center of force (COF), implant force percentage (IF %), occlusion time (OT), disclusion time (DT), and excursive positions were evaluated for the implants and the adjacent natural teeth. Data were collected, tabulated, and presented as frequencies and percentages. Results: 25% of the treated implant cases were reported to have optimum implant occlusion time (OT < 0.6s) and to have received implant force percentage (IF%) less than the adjacent natural teeth. Moreover, 5 implants (12.5%) were out of occlusion. <br />Conclusion: The use of the articulating paper is not an accurate enough method to employ in the implant occlusion adjustment, while the use of the T-Scan occlusal analyzer as a quantifying, non-subjective occlusal indicator may produce more comprehensive and evidence-based results.
occlusion,single implant-prosthetic restoration,articulating paper,T-Scan III occlusal analyzer
https://edj.journals.ekb.eg/article_76211.html
https://edj.journals.ekb.eg/article_76211_57f2200636339b140e167d3a093fc259.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
SURFACE COMPOSITION AND NANO-MECHANICAL PROPERTIES OF HUMAN ENAMEL BRUSHED WITH TOOTHPASTE STANDARDIZED BY 10 WT % NANO-HYDROXYAPATITE
2607
2617
EN
Dalia
M
Abdel-Hamid
Assistant Professor of Dental Materials Science, Biomaterials Department, Faculty of Dentistry, Cairo University,
Egypt.
Norhan
A
El-Dokky
Assistant Professor of Pedodontics, Pediatric and Community Dentistry Department, Faculty of Dentistry, Cairo
University, Egypt
Sherif
B
El-Tawil
Assistant Professor of Pedodontics, Pediatric and Community Dentistry Department, Faculty of Dentistry, Cairo
University, Egypt
10.21608/edj.2017.76212
Purpose: Evaluation of the effect of simulated brushing with toothpaste standardized by 10 wt. % nano-hydroxyapatite (n-HAp) for one year on the surface composition and nano-mechanical properties (hardness and elastic modulus) of human enamel. <br />Study design: 20 sliced human enamel/dentin slabs were divided into: control group (brushed with a commercial toothpaste) and test group (brushed with the same toothpaste with 10 wt. % n-HAp ~20 nm). Brushing was performed for one hour/day for 24 days. The nano-hardness and elastic modulus were measured (GPa) by the nano-indenter. SEM and EDXA were performed to study the morphology, thickness and the chemical composition of enamel surface. The Ca/P ratio was calculated (at. %). The data were statistically analyzed. <br />Results: Insignificant difference (P = 0.070) between the nanohardness values of the 2 groups was obtained. However, the elastic modulus of the control group was significantly lower than that of the test group (P = 0.019). SEM of the test group revealed the precipitation of n-HAp layer (~5 µm thick). The Ca/P ratios and the other minerals of the two groups were not significantly different. <br />Conclusions: Using dental products containing ≥10 wt. % n-AHp should be restricted to patients susceptible to demineralization; to avoid their detrimental effect on the elastic modulus that could be negatively reflected clinically on the mechanical behavior of the teeth.
Surface composition,Nano-mechanical,enamel,nano-hydroxyapatite,Brushing,Toothpaste
https://edj.journals.ekb.eg/article_76212.html
https://edj.journals.ekb.eg/article_76212_ff354ea69a36f6cb91261bbf35a028cf.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
HARD TISSUE RESPONSE COMPARISON IN AN IMPLANT OVERDENTURE RETAINED BY LOCATOR OR EQUATOR ATTACHMENTS. A RANDOMIZED CLINICAL TRIAL
2619
2627
EN
Ahmed
Fayyad
Lecturer of Prosthodontics, Faculty of Dentistry, Cairo University.
Ahmed
M.
Abd Alsamad
Lecturer of Oral and Maxillofacial Radiology, Faculty of Dentistry, Cairo University.
10.21608/edj.2017.76214
Introduction: Completely edentulous patients usually have many problems associated with their mandibular complete dentures. Dental implants solved many of these problems. Many attachments are used nowadays to retain mandibular overdenture to dental implants. Among these attachments are the low profile locator and equator attachments. This study was conducted to study the effect of both attachments on bone level around two implants retaining complete mandibular overdenture. <br />Methodology: This study was conducted on 10 completely edentulous patients. Two implants were installed in the canine region bilaterally for all patients. Patients were then randomly divided into two groups where the first group received implant supported mandibular overdenture retained by locator attachment, while the other group received implant supported mandibular overdenture retained with equator attachment. The patients were then referred to oral and maxillofacial radiology department, Faculty of Dentistry, Cairo University for radiographic assessment to measure the bone height and density changes around the implant at the day of overdenture delivery and 12 months later.<br />Results: In the current study, bone height changes in both groups was in the clinically permissible range. Regarding bone density, it increased gradually around the loaded implants in both groups. When density is compared between the two groups, the locator attachment group showed significant increase when compared to the equator attachment group after 12 months of prosthetic loading.<br />Conclusions: Within the limitation of this study, both locator and equator attachments are viable treatment options to retain an implant supported mandibular complete overdenture regarding hard tissue response around the implants but more studies with more extended follow up is recommended.
mandibular overdenture,Implants,Locator attachment,Equator attachment
https://edj.journals.ekb.eg/article_76214.html
https://edj.journals.ekb.eg/article_76214_ed35a45ca36410e653894e6eb5a8197d.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
ZIRCONIA VERSUS METAL CAD/CAM EXTRACORONAL ATTACHMENTS FOR THE BILATERAL DISTAL EXTENSION REMOVABLE PARTIAL MAGNET VERSUS OLS ATTACHMENTS FOR IMPLANT OVERDENTURES: A STRESS ANALYSIS STUDY
2629
2637
EN
Nagla
Nassouhy
Lecturer of Removable Prosthodontics, Cairo University
Mohamed
Farouk
Abdalla
Associate Professor of Removable Prosthodontics, Cairo University
10.21608/edj.2017.76218
Objectives: To compare between the effect of zirconia and metal CAD/CAM fabricated attachments on alveolar bone height of the residual ridge and periodontal health of abutment teeth in cases with bilateral distal extension base.<br />Materials and Methods: Seven Kennedy class I patients were selected for this study. In a split-mouth manner, one side of the arch received metal attachment together with porcelain fused to metal fixed partial denture, while the other side received zirconia attachment connected to zirconia fixed restoration. Alveolar bone loss, bleeding on probing (BOP) and pocket depths (PD) were measured for each side at the time of delivery and at 6 and 12 months post-insertion. <br />Results: There was no statistically significant difference between the two attachments regarding bone loss in the residual ridge in all follow-up appointments. There was also no significant bone loss for each attachment by the end of the follow-up period. There was no significant difference in BOP and PD at 6 months, but there was a significant increase in BOP and PD for both attachments at 12 months post-insertion. However, the difference between the two attachments was not statistically significant at any follow-up appointment.<br />Conclusions: Zirconia attachment yields comparable clinical and radiographic results as metal attachments for distal extension cases within a follow-up period of one year.
https://edj.journals.ekb.eg/article_76218.html
https://edj.journals.ekb.eg/article_76218_9e255c1fe625a8fe43578abddf788c09.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
EVALUATION OF THE DEFECTS IN RECIPROCATING AND ROTATING NICKEL-TITANIUM FILES USED AS A SINGLE FILE TO PREPARE MOLAR TEETH
2639
2649
EN
Wafaa
A.
Khalil
Associate Professor, Department of Endodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
Tariq
S.
Abu-Haimed
Assistant Professor, Department of Conservative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah,
Saudi Arabia
10.21608/edj.2017.76221
Aim: To evaluate the defects in five nickel-titanium instruments activated by reciprocating and rotating motions and used as a single file in molar teeth. <br />Materials and methods: Twenty files size 25 from five brands [WaveOne (WO); Reciproc (RC); OneShape (OS); ProTaper Next (PTN); and ProTaper Universal (PTU)] were tested as a single file to prepare mandibular molars teeth. Thereafter, the five brands were redistributed into two tested groups, rotating and reciprocating groups. The time required for instrumentation was recorded. New and used instruments were examined under a scanning electron microscope for defects, deformations and fractures. One-way ANOVA and Kruskal Wallis were used for data analysis. <br />Results: The RC and PTN were significantly faster than WO and OS (P<0.05), while PTU required significantly the longest time (P<0.05). The fracture incidence was zero % in the PTN and OS, and 5% in the WO and RC, while it was (10 %) in the PTU. The fractographic analysis revealed cyclic failure of PTU and WO and torsional failure in RC. OS had (15%) percentage of deformation, WO (5%), while it was zero% in the PTN, RC and PTU. Reciprocating motion was significantly faster than rotating motion (P<0.05) without significant difference in deformation incidence (P>0.05). <br />Conclusions: The ProTaper Next, Reciproc and WaveOne files, were less vulnerable to fracture and deformation than ProTaper Universal and OneShape files when used as a single file to prepare molar teeth. The ProTaper Next was faster and more resistant to failure than other groups. In addition, files used with the reciprocating motion were faster to finish molar teeth than rotating motion without a significant effect on the defect incidence.
https://edj.journals.ekb.eg/article_76221.html
https://edj.journals.ekb.eg/article_76221_51ab373ae01a975fd075cfb831b1d459.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
MICRO SHEAR BOND STRENGTH EVALUATION FOR IMMEDIATELY SEALED DENTINE WITH HYBRID CERAMICS AFTER DIFFERENT PROVISIONALIZATION PERIODS: IN VITRO STUDY
2651
2659
EN
Maha
Taymour
Lecturer Fixed Prosthodontic Department, Faculty of Oral and Dental Medicine. Cairo University.
Reham
Elbasty
Lecturer Fixed Prosthodontic Department, Faculty of Oral and Dental Medicine. Cairo University.
10.21608/edj.2017.76223
Statement of the problem: CAD/CAM restorations can be immediately cemented after tooth preparation, however, a delay between final impression and restoration delivery is sometimes unavoidable, thus provisionalization period becomes necessary. There are concerns whether this delay would affect the dentin bond strength when bonding to immediately sealed dentin. <br />Purpose: to study the effect of different provisionalization periods (1 and 3 weeks) on the bond strength of immediately sealed dentin to two types of hybrid ceramics <br />Materials and Methods: A total of sixty ceramic discs were fabricated in this study from CAD/CAM blocks. The discs were divided into two groups; Group 1: Thirty discs were constructed from polymer-infiltrated-ceramic-network material (VITA Enamic) and Group 2: Thirty discs constructed from resin nanoceramic (CERASMART). Each of the previous groups were further subdivided into three equal subgroups according to the provisionalization period as follows; Subgroup 1: Ten discs were cemented to immediately sealed dentin without any provisionalization period, Subgroup 2: Ten discs were cemented to immediately sealed dentin after 1 week of provisionalization and Subgroup 3: Ten discs were cemented to immediately sealed dentin after 3 weeks of provisionalization. Teeth were trimmed to have a flat, midcoronal dentin surfaces. This was followed by immediate dentin sealing of the exposed dentin. Ceramic samples were then obtained by slicing the CAD/CAM blocks with standardized dimensions. For subgroup 1, adhesive cementation was immediately done for the ceramic samples to immediately sealed dentin. For subgroup 2 and 3, the sealed surfaces were coated with a layer of petroleum gel followed by application of a provisional restoration for 1 and 3 weeks respectively. The samples were then immersed in saline solution until the end of the provisionalization period. At the end of these various periods, the provisional restoration was removed and the sealed dentin was cleaned by pumice and water followed by roughening with a coarse diamond stone. This was followed by adhesive cementation of the discs. Micro shear bond strength test was then performed to debond the specimens in a universal testing machine (Lloyd Instruments Ltd, Hampshire, UK) with a crosshead speed of 0.5 mm/s. The maximum load at failure was recorded in Newtons (N) unit and was divided over the bonded area (mm2) to convert to MPa unit. Data was then collected, tabulated and statistically analyzed. <br />Results: For CERASMART group: It was found that the highest shear bond strength mean±SD values were recorded with no provisionalization subgroup (9.37±0.35MPa) followed by 1 week provisionalization subgroup (8.4±0.12MPa) while the lowest shear bond strength mean±SD values were after 3 weeks provisionalization subgroup (4.48±0.23MPa). The difference between provisionalization subgroups was statistically significant (p=<.0001<0.05) as indicated by one way ANOVA test. Pair-wise Tukey’s post-hoc tests showed no significant difference (p>0.05) between (no- provisionalization and 1 week provisionalization) subgroups. For Vita Enamic group: It was found that the highest shear bond strength mean±SD values were recorded with 3 weeks provisionalization subgroup (7.3±0.67MPa) followed by no provisionalization subgroup (7.08±1MPa) while the lowest shear bond strength mean±SD values were after 1 week provisionalization subgroup (5.59±0.71MPa). The difference between all subgroups was statistically non-significant (p=0.2192 >0.05) as indicated by one way ANOVA test. Effect of ceramic: With no provisionalization; it was found that CERASMART group recorded statistically non-significant higher shear bond strength mean value (9.37±0.35 MPa) than Vita Enamic group (7.08 ±1 MPa) as indicated by t-test (p=0.0598>0.05). After 1 week provisionalization; it was found that CERASMART group recorded statistically non-significant higher shear bond strength mean value (8.4 ± 0.12 MPa) than Vita Enamic group (5.59±0.71 MPa) as indicated by t-test (p=.0540 >0.05). After 3 weeks provisionalization it was found that Vita Enamic group recorded statistically significant higher shear bond strength mean value (7.3±0.67 MPa) than CERASMART group (4.48±0.23 MPa) as indicated by t-test (p=.0089<0.05).<br />Conclusions: 1) The effect of provisionalization period on microshear bond strength of immediately sealed dentin with indirect restorations is ceramic type dependant. 2) When it is inevitable to cement the final restoration within 3 weeks, Vita Enamic ceramic would be a preferred choice compared to CERASMART as it provided higher bond strength when IDS protocol is used. 3) When final restoration cementation is planned immediately or within 1 week of IDS, both ceramics can be used as the difference between them was insignificant.
https://edj.journals.ekb.eg/article_76223.html
https://edj.journals.ekb.eg/article_76223_7f926df31072ce2489e0484e30e279b5.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
THE EFFECT OF MAGNETIC AND LOCATOR ATTACHMENTS ON STRAIN AROUND IMPLANTS RETAINING MANDIBULAR OVERDENTURE: AN IN VITRO STUDY
2661
2669
EN
Ahmed
Fayyad
Lecturer of Prosthodontics, Faculty of Dentistry, Cairo University
10.21608/edj.2017.76224
Objectives: This in-vitro strain gauge study was conducted to compare between magnetic and locator attachments regarding strain induced around two implants supporting a mandibular overdenture. <br />Methodology: The study was performed on acrylic models of a completely edentulous mandibular arch with two implants installed bilaterally at the canine areas. The strain induced around the implants was studied during unilateral and bilateral loading at the first molar area using a universal testing machine. <br />Results: The results of this study showed that there was no statistically significant difference between the two studied groups during unilateral loading with higher values in the locator attachment group while during bilateral loading there was a statistically significant difference between the two groups but with higher micro-strain values for the magnetic attachment group <br />Conclusion: Within the limitation of this in-vitro study, it could be conclude that the attachment type could have an effect on the amount of load that will be transmitted to the implants supporting an over denture. Clinical studies are required to evaluate the effect of type of attachment on peri-implant crestal alveolar bone loss and correlate it with the results of the current study.
In-vitro study- Strain gauge analysis-magnetic attachment- locator attachment-Overdenture
https://edj.journals.ekb.eg/article_76224.html
https://edj.journals.ekb.eg/article_76224_ed7eb4389efe03425d8419aadaf374d9.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
MAGNET VERSUS OLS ATTACHMENTS FOR IMPLANT OVERDENTURES: A STRESS ANALYSIS STUDY
2671
2679
EN
Nagla
Nassouhy
Lecturer of Removable Prosthodontics, Cairo University
10.21608/edj.2017.76226
Objectives: to compare between the microstrains transmitted to the implants with magnetic and OLS attachments in 2-implant overdentures. <br />Methodology: two dummy implants 3.7 mm in diameter and 12mm in length were placed in an acrylic resin model resembling a completely edentulous mandible. Attachment pick up was done for the magnetic attachment followed by loading and measurement. Four Strain gauges were used to measure microstrains around the implants during unilateral and bilateral loading using a universal testing machine and a multi-channel strain meter. The procedure was repeated for the OLS attachment. Measurements were tabulated and statistically analyzed. <br />Results: loading sides demonstrated significantly higher microstrains around the implants with the two attachments than non-loading sides. OLS attachment showed significantly higher microstrains than magnetic attachment for both loading and non-loading sides during unilateral loading. During bilateral loading, there was no significant difference between the two attachments. <br />Conclusion: implant overdentures retained by magnetic attachments transmit less stresses to the implants than OLS attachments with PEEK retentive matrices during unilateral loading. During bilateral loading, the stresses transmitted by the two attachments were comparable.
https://edj.journals.ekb.eg/article_76226.html
https://edj.journals.ekb.eg/article_76226_69503b645b6feddc6f017158aa322f1d.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
IMPACT OF VARIOUS IMPRESSION TECHNIQUES ON MAXILLARY FLABBY RIDGE TISSUE DISPLACEMENT (WITHIN-SUBJECT EVALUATION)
2681
2689
EN
Amira
Gomaa
Associate Professor of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
Nesreen
El Mekawy
Associate Professor of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
10.21608/edj.2017.76228
Purpose: This study was conducted to determine the effect of various impression techniques on the displacement of flabby tissues overlying the edentulous maxillary ridge. In this study Ten completely edentulous maxillary arches patients with anterior flabby ridges participated in this study. For each patient five secondary impressions were recorded and divided into five groups according to impression technique used. Group I: comprised impressions following the mucocompressive technique. While, in Groups II, III, IV and V had used different mucostatic impression techniques. Soft tissue displacements in X, Y, Z axes and total 3-D in relation to a fixed reference point were recorded for each impression using modified Measurescope. The data were collected and statistically analyzed. The results obtained showed that there were significant differences in soft tissue displacement of all tested groups in both three coordinates (X, Y and Z) and total 3-D. Also; the results showed significant difference in soft tissue displacement of tissues recorded by the four mucostatic impression technique groups compared to mucocompressive impression technique. A significant difference was found between one step mucostatic impression technique group, and two step mucostatic impression techniques. <br />Conclusions: Based on the results of this study, soft tissue displacement of maxillary flabby ridge during impression procedure occurred along X, Y and Z directions for all tested impression techniques. The mucostatic impression techniques generated less soft tissue displacement than the mucocompressive technique. Two-step mucostatic impression techniques produced less soft tissue displacement compared to the one step mucostatic impression technique.
Maxillary anterior flabby ridges,soft tissue displacement,mucocompressive impression technique,mucostatic impression techniques
https://edj.journals.ekb.eg/article_76228.html
https://edj.journals.ekb.eg/article_76228_80285179262f947dd92fd21515374f37.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
ACCURACY OF TWO DIFFERENT IMPRESSION MATERIALS IN PARALLEL AND NON PARALLEL IMPLANT POSITIONS
2691
2699
EN
Ahmed
M.
Alam-Eldein
Lecturer, Prosthodontic department, Faculty of dentistry, Tanta University,
Enas
A.
Elshenawy
Demonstrator, Dental Biomaterials department, Faculty of dentistry, Tanta University
10.21608/edj.2017.76231
Purpose: Accurate implant impressions play a significant role and serve as a starting point in the process of producing good working casts. This study was designed to evaluate the effect of two different impression materials, additional silicone (Enthus) and vinyl siloxanether (EXA’lence), on the accuracy of impressions in parallel and nonparallel implants.<br />Material and Methods: In this study, two completely edentulous mandibular models were used. Three implants (OsseoLink USA LLC. 4 mm ×9 mm, internal connection type) were placed in each reference model with different angles (0 and 15 degrees). Thirty stone casts were made from each reference model using additional silicone (Enthus polyvinyl siloxane, PVS) and vinyl siloxanether (EXA’lence, VSXE) (n=15 per group) with direct technique. The inter-implant distances were measured for casts using a coordinate measuring machine and the deviations compared to the reference models were calculated. Data were collected, tabulated and statistically analyzed using Student T-test.<br />Results: In parallel condition, the two materials showed non-significant difference in deformation of (∆ r1 or ∆ r2), while in the presence of angulated implants, vinyl siloxanether (EXA’lence, VSXE) impression material showed more accurate results compared to additional silicone (Enthus polyvinyl siloxane, PVS) impression material.<br />Conclusion: Within the limitations of this study, in parallel conditions, the type of impression material cannot affect the accuracy of the implant impressions; however, in nonparallel conditions, vinyl siloxanether (EXA’lence, VSXE) impression material produced more accurate casts than additional silicone (Enthus polyvinyl siloxane, PVS) impression material.
dental implant,Polyvinyl siloxane,Vinyl siloxanether
https://edj.journals.ekb.eg/article_76231.html
https://edj.journals.ekb.eg/article_76231_e8f4c62861b19d3ff54d4bd5c1c1e8e2.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
EVALUATION OF RETENTION PROPERTIES OF TWO DIFFERENT STUD ATTACHMENTS IN MANDIBULAR IMPLANT OVERDENTURES
2701
2707
EN
Nada
Sherin
El Khourazaty
Lecturer of removable Prosthodontics, Faculty of Dentistry, Cairo University
10.21608/edj.2017.76232
Objectives: The aim of this study was to compare the retention values of two stud attachments with two different designs in Mandibular implant overdenture. <br />Materials & methods: Eight completely edentulous patients were selected to receive mandibular complete overdentures supported by 4 implants. At the prosthetic phase the patients were divided into two groups; Group I: 4 Patients of this group received a mandibular overdenture retained by a ball abutment and a nylon matrix, Group II: 4 Patients of this group received a mandibular overdenture retained by OLS attachment with a PEEK matrix. Retention values were measured in vitro using universal testing machine at the time of installation, 6 and 12 months. <br />Results: The results of this study demonstrated no significant difference between the conventional ball with nylon cap and the PEEK attachment at the installation time, while analysis of the retentive values after 6 and 12 months showed a significant decrease in retention values of the ball and socket attachment with nylon matrix, while the OLS attachment with PEEK matrix showed higher retentive means compared to the ball. <br />Conclusion: Within the limitation of this study it was concluded that PEEK OLS attachment attains better values of retention with time when compared to conventional ball and socket attachments with nylon matrix.
https://edj.journals.ekb.eg/article_76232.html
https://edj.journals.ekb.eg/article_76232_f6b2376f21038f281786cb47eee45008.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
COMPRESSIVE STRENGTH AND SURFACE ROUGHNESS OF CERAMIC REINFORCED GLASS IONOMER SUBJECTED TO CHEMICAL CHALLENGE
2709
2719
EN
Randa
M.
Hafez
Professor, Conservative Dentistry Department, Faculty of Oral and Dental Medicine, Cairo University
Maha
E.
Elkorashy
Lecturer, Operative Dentistry Department, Faculty of Dentistry, Fayoum University
Mayada
S.
Sultan
Lecturer, Operative Dentistry Department, Faculty of Dentistry, Assiut University
10.21608/edj.2017.76235
Objective: This research was conducted to investigate the effect of chemical challenge on the compressive strength (CS) and surface roughness (Ra) of a ceramic reinforced glass ionomer in comparison to a nanofilled resin composite. <br />Methods: A total of 60 disc specimens (6mm height x 4mm diameter) were prepared for the compressive strength testing and another 60 disc specimens (5mm diameter x 2mm thickness) for the surface roughness testing. Specimens were divided into 2 groups (n=30) according to the material used; ceramic reinforced glass ionomer (Amalgomer CR, Advanced Health Care Ltd, Tonbridge, Kent, UK) and nanofilled resin composite (FiltekTM Z350 XT, 3M ESPE, St.Paul, MN,USA). Each group was divided into 3 subgroups (n=10) according to the storage media; distilled water (control), 0.02N citric acid and 50% ethanol. Specimens were stored for 7 days at 37ºC. After storage period, they were subjected to compressive loading using a universal testing machine and surface roughness testing using white light interferometer. Data were tabulated and statistically analyzed using Two-way ANOVA followed by Bonferroni’s post-hoc test.<br />Results: Amalgomer CR recorded a significantly lower CS and higher Ra than nanofilled resin composite under different storage media. Citric acid revealed the lowest CS of Amalgomer CR followed by ethanol in comparison to distilled water with significant difference between them. For nanofilled resin composite, both citric acid and ethanol significantly decreased CS. Ethanol showed the highest Ra values for both restorative materials. <br />Conclusions: The performance of Amalgomer CR under different storage media was inferior to nanofilled resin composite regarding compressive strength and surface roughness. Citric acid severely affected compressive strength of Amalgomer CR. Nanofilled resin composite was able to preserve its surface roughness within the clinically acceptable threshold after chemical challenge in contrary to Amalgomer CR.
ceramic reinforced glass ionomer,Citric acid,ethanol,Compressive strength,Surface roughness
https://edj.journals.ekb.eg/article_76235.html
https://edj.journals.ekb.eg/article_76235_383091e6edbee1a1baf8509c92173703.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
AN IN VITRO STUDY TO EVALUATE THE COLOR STABILITY OF FOUR DIFFERENT CAD/CAM CERAMICS
2721
2735
EN
Rana
M
Sherif
Assistant Professor, Fixed Prosthodontics Department, Faculty of Oral and Dental Medicine, Cairo University,
Egypt.
10.21608/edj.2017.76236
Statement of the problem: Dental Ceramics have been widely used in patients seeking ultimate esthetics, however still there is concern about their color stability by time.<br />Aim of the study: To evaluate the color stability of four different CAD/CAM ceramics after immersion in coffee solution.<br />Materials and Methods: A total of twenty ceramic discs with shade A2 (10 mm in diameter and 2mm in thickness) were constructed in standardized manner. Samples were divided into four main equal groups (n=5) each, according to the type of ceramic material used. Group I: IPS e.max CAD. Group V: Vita Suprinity. Group C: Cerec Blocs. Group O: Obsidian. All specimens were fabricated using CNC milling machine and electric isoMet microsaw 4000. A specially constructed cylindrical split teflon mold was fabricated for the construction of twenty composite resin discs shade A3 (10 mm in diameter and 2mm in thickness). Both ceramic and composite discs were constructed according to manufacturer instructions then were adhesively luted using dual cure Rely X U200 Automix self-Adhesive resin cement shade A2 under 2 Kg constant load application. All disc samples were immersed in coffee solution for 3 weeks and were tested twice; before (baseline) and after the immersion. The color of each sample was then assessed using a spectrophotometer. The L* a* b* values of the samples were recorded according to the CIELAB color scale relative to the standard illumination D65. The results were tabulated and statistically analyzed as mean, standard deviation (SD), median, range and with 95% Confidence interval values. For parametric data, one-way ANOVA was used followed by Tukey’s post-hoc test to compare between the four groups. While for non-parametric data, Kruskal-Wallis test was used to compare between the four groups. The significance level was set at P ≤ 0.05. Statistical analysis was performed with IBM® SPSS® Statistics Version 20 for Windows.<br />Results: There was a statistically significant difference between the four ceramic groups after immersion in coffee solution. A decrease in (L*) values was found in all groups. Pair-wise comparisons revealed that IPS e.max CAD showed the highest mean decrease in (ΔL) (-5.19±0.71).
https://edj.journals.ekb.eg/article_76236.html
https://edj.journals.ekb.eg/article_76236_b677aa1422471d9c6e201a64b24a24eb.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
QUANTITATIVE ASSESSMENT OF APICALLY EXTRUDED DEBRIS AND RETREATABILITY OF TWO SEALERS USING TWO ROTARY RETREATMENT SYSTEMS
2737
2745
EN
Abeer
Saba
Assistant Professor of Endodontics, Endodontic Department, Faculty of Dentistry, Cairo University
Reham
Saeed
Seyam
Assistant Professor of Endodontics, Endodontic Department, Faculty of Dentistry, Cairo University
Dalia
A.
Saba
Lecturer of Dental Materials Science, Biomaterials Department, Faculty of Dentistry, Cairo University
10.21608/edj.2017.76238
Objective: Quantitative assessment of apically extruded debris and retreatability of two sealers using two rotary retreatment systems<br />Methodology: Two NiTi rotary file systems; ProTaper Universal (PT) retreatment files (Dentsply-Maillefer, Ballaigues, Switzerland) and Mtwo R retreatment (MT) rotary files (Sweden and Martina, Padova, Italy) and two sealers; AH Plus (Dentsply International Inc., York, PA, USA) and SmartPaste Bio (DRFP Ltd., Stamford, UK) were used in this study. The root canals of 40 single-rooted human premolar teeth having nearly similar length were prepared. The prepared root canals were obturated with gutta-percha and either AH Plus or Smart Paste Bio sealers (n=20/group). Each group was then sub-divided into two subgroups (n = 10 lsubgroup) according to whether the root filling material was removed using either Protaper Universal retreatment or MTwo Retreatment Kit.<br />After retreatment, the apically extruded debris was collected in Eppendorf tubes which were weighed before and after retreatment with an electronic balance. The retreatability of the both sealers was assessed using CBCT imaging by calculating the volume of the residual filling material post-treatment in the middle and apical thirds of the root canals. Results were statistically analyzed using one-way-analysis-of-variance; (P<0.05).<br />Results: Statistically, there was no significant difference in the weight of collected apically extruded debris nor in in the remaining volume of the obturating materials between all groups (P=0.849 and P=0.8831), respectively. <br />Conclusions: All investigated retreatment techniques caused debris extrusion and left filling remnants inside the root canals. SmartPaste Bio sealer is as retreatable as AH Plus sealers.
AH Plus sealer,Apical debris extrusion,CBCT,endodontic retreatment,Protaper retreatment,Mtwo R,Smart Paste Bio sealer
https://edj.journals.ekb.eg/article_76238.html
https://edj.journals.ekb.eg/article_76238_cb62e4c101ed43b4507eb217ce669b6e.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
COMPARING PATIENT SATISFACTION, RETENTIONAND MAINTENANCE FOR DIFFERENT SOLUTIONS OF MIDLINE FRACTURE OF IMPLANT RETAINED MANDIBULAR OVERDENTURES
2747
2757
EN
Nora
Mohamed
Sheta
Lecturer, Department of Prosthodontics, Faculty of Dental Medicine, Cairo University
10.21608/edj.2017.76239
Purpose: The purpose of this study was to evaluate Patient Satisfaction, Retention and Maintenance of Repaired midline fracture Implant Retained Mandibular Overdentures by different methods of repair: a) Direct re-assembly of the denture b) Reinforcement of the fitting surface with a metal framework.<br />Materials and methods: 45 completely edentulous patients seeking for implant installation in the mandible were included in this study. All patients had received single midline implant & a stud attachment; 3-4 months after implant installation. Patients were rehabilitated with implant retained overdentures. Bone height changes, retention and patient satisfaction were evaluated at regular recall visits for one year. 14 patients had reported midline fracture of their mandibular overdentures at the follow up period from 3 to 6 months. The 14 patients were randomly divided in two groups; Group (a): Included seven patients had the fractured denture repaired by direct reassembly using self- cured acrylic resin. Group (b): Included seven patients; had the fractured denture reinforced with a metal framework embedded in the fitting surface of the denture. Patient satisfaction, overdenture retention, and prosthetic maintenance were assessed after dentures repair for patients of the two groups. Evaluation was carried-out at the day of dentures insertion after repair, 2 weeks, 3 months and 1 year after dentures’ repair<br />Results: The results of this study had revealed that Group (b) patients rehabilitated with (Dentures repaired by Reinforcing metal framework) had reported significant improvement in the patients satisfaction, significant decrease in the prosthetic maintenance required after 1 year follow-up compared to patients of Group:(a) patient rehabilitated with (Dentures repaired with direct reassembly using self cure acrylic resin). After 1 year follow up, there was no significant difference in the mean values of retention in both studied groups. <br />Conclusions: Within the limitations of the present study; the following conclusions may be achieved: For a single implant retained mandibular overdenture, midline fracture may better repaired by reinforcement of denture base with a metal framework embedded in the fitting surface of the denture. Metal reinforcement may increase the rigidity of the overdenture, improve the patient satisfaction and may decrease the number of visits required for maintenance.
https://edj.journals.ekb.eg/article_76239.html
https://edj.journals.ekb.eg/article_76239_b20d695dd82a832e9d35c5f98da6057d.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
DIMENSIONAL ACCURACY OF DIRECT AND INDIRECT IMPLANT IMPRESSION TECHNIQUES FOR COMPLETELY EDENTULOUS PATIENTS
2759
2769
EN
Yasmeen
Fat’hy
Al-Mahdy
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine (girls’ branch), AlAzhar University
Hala
Mohamed
Gamal El Din
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine (girls’ branch), AlAzhar University
Dina
Mahmoud
Kholief
Assistant Professor of Removable Prosthodontics, Faculty of Dental Medicine (girls’ branch), AlAzhar University
10.21608/edj.2017.76243
Background: Accurate recording of implant location is required for a successful definitive restoration. <br />Aim: This study was conducted to compare the accuracy of two implant impression techniques (direct and indirect) in transferring implant positions to the master casts in comparison to implant position in patients’ mouth using radiographic imaging.<br />Materials and Methods: Ten completely edentulous male patients were selected. 2 Root-form implants 3.7 mm in diameter and 16 mm in length were utilized in this study in the canine regions. For each patient two special trays were fabricated, one for the registration of direct impression technique and the other for the indirect impression technique. Cone beam computed tomography (CBCT radiograph) was done for all patients, the casts obtained from direct and indirect implant impression techniques were taken to evaluate the accuracy of the two impression techniques in comparison with the patients’ radiographs regarding the distance between the implants. The horizontal dimensional accuracy of the impression techniques was determined by measuring the inter-implants’ distance in the x-axis between the copings. Measurements were done on radiographic images of the following; casts obtained from direct impression technique, casts obtained from indirect implant impression technique and radiographs of patients.<br />Results: The mean and SD values of casts radiographs obtained from both impression techniques and from patients’ radiographs were calculated. Group I (Deviation of distance between direct impression technique and patients’ radiograph) had a mean value of 1.45mm (SD 0.03); Group II (Deviation of distance between indirect impression technique and patients’ radiograph) had a mean value of 2.08 mm (SD 0.04). The direct impression technique showed more accurate results. <br />Conclusion: Casts obtained from the direct impression technique were significantly more accurate than those obtained from indirect impression technique. Comparison of both impression techniques retrieved from patients in relation to patients’ CBCT provided more reliable results than in vitro studies. So this study suggests that direct impression technique is more accurate.
impression coping,impression technique,impression accuracy,implant misfit,direct impression technique,indirect impression technique
https://edj.journals.ekb.eg/article_76243.html
https://edj.journals.ekb.eg/article_76243_5bf3fab93f83e2fea7304d8651ac4a43.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
FRACTURE RESISTANCE AND FAILURE MODE OF TWO RESTORATION DESIGNS MADE OF MONOLITHIC HYBRID AND GLASS MACHINABLE CERAMICS ; IN VITRO STUDY
2771
2783
EN
Carl
Hany
Associate Professor, Fixed Prosthodontics Department, Faculty of Oral and Dental Medicine. Cairo University.
Maha
Taymour
Lecturer, Fixed Prosthodontics Department, Faculty of Oral and Dental Medicine. Cairo University.
10.21608/edj.2017.76323
Statement of the problem: Monolithic hybrid and glass ceramics are indicated for intracoronal and extracoronal ceramic restorations. Available data regarding selection of the appropriate ceramic type for each preparation design and its influence on fracture resistance of tooth restoration complex is still scarce.<br />Purpose: The purpose of this study was to evaluate in vitro the fracture resistance and investigate failure mode of two restoration designs (crowns and inlays) made from lithium disilicate glass ceramic and hybrid ceramic constructed by the CAD /CAM technique.<br />Materials and Methods: A total of twenty ceramic restorations restoring lower molars were designed and fabricated in this study. The restorations were divided into two groups; Group 1: Ten full coverage crowns and Group 2: Ten inlays. Each of the previous groups was further subdivided into two equal subgroups; Subgroup 1: Five restorations constructed from lithium disilicate glass ceramics (e.max CAD) and Subgroup 2: Five restorations constructed from hybrid ceramic (VITA ENAMIC) by the CAD/CAM technology. Two ivorine teeth were prepared following the guidelines for full coverage and inlay ceramic restorations, they were duplicated into stone dies followed by scanning, designing and milling of restorations. The stone dies were duplicated into epoxy dies where the restorations were adhesively cemented on them. All cemented samples were exposed to 2000 thermal cycles (5°C and 55°C in water) with a dwell time of 25 seconds in a computer controlled thermocycler. All specimens were loaded in a universal testing machine where fracture test was done by compressive mode of load applied occlusally using a metallic rod with round tip at cross-head speed of 1mm/min until fracture occurred. Fracture resistance values were recorded in Newtons then they were statistically evaluated and failure modes were analyzed. <br />Results: For group 1 representing crown restorations, a statistically significant difference was found between (e.max CAD) and (VITA ENAMIC) subgroups at (p=0.05) where the highest mean value of maximum load was found in (VITA ENAMIC) (951.77 N ± 81.05) and the lowest mean value of maximum load was found in (e.max CAD) (709.35 N± 49.51). While for the second group representing inlay restorations, no statistically significant difference was found between (e.max CAD) and (VITA ENAMIC) subgroups at (p=0.307) where the highest mean value of maximum load was found in (e.max CAD) (627.71 N ± 80.01) and the lowest mean value of maximum load was found in (VITA ENAMIC) (581.26 N± 51.74). For the e.max CAD subgroup, a statistically significant difference was found between (Crown) and (Inlay) groups at (p=0.005) where the highest mean value of maximum load was found in the crown group (790.35 N± 49.51) and the lowest mean value of maximum load was found in the inlay group (627.71N ± 80.01).Regarding the VITA ENAMIC subgroup, a statistically significant difference was found between (Crown) and (Inlay) groups at (p<0.001) where the highest mean value of maximum load was found in the crown group (951.77 N ± 81.05) and the lowest mean value of maximum load was found in the inlay group (581.26N±51.74).<br />Conclusions: 1. All inlays and crowns constructed from hybrid and glass ceramics in this study revealed fracture load values falling in the range of physiologic masticatory forces 2. When considering restoration of molars with full coverage crowns, VITA ENAMIC is more preferred than e.max CAD ceramic in terms of fracture resistance as it showed a higher statistical significant mean values.3. When planning to restore molars with minimally invasive intracoronal restorations, both ceramics can be used as there was insignificant statistical difference between them , however e.max CAD can be recommended due to its more favorable mode of fracture compared to VITA ENAMIC.4. Irrespective of preparation designs, both ceramics showed insignificant difference regarding fracture resistance mean values.
https://edj.journals.ekb.eg/article_76323.html
https://edj.journals.ekb.eg/article_76323_c8f7a7c6949e63a8a55b0160d2ac4438.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
FLEXURAL STRENGTH AND ADHESION OF ZIRCONIA-REINFORCED LITHIUM SILICATE GLASS CERAMIC TO RESIN CEMENT AFTER THERMO-MECHANICAL LOAD CYCLING
2785
2793
EN
Tarek
A.
Soliman
Lecturer of Dental Biomaterials, Dental Biomaterials Dept., Faculty of Dentistry, Mansoura University, Egypt.
10.21608/edj.2017.76325
Purpose: The aims of this study were to evaluate the flexural strength and adhesion of zirconia-reinforced lithium silicate glass ceramic with those of lithium disilicate after applying a combined thermo-mechanical load cycling. <br />Materials and Methods: Zirconia-reinforced lithium silicate (vita suprinity; SV) and lithium disilicate glass ceramics (IPS e.max CAD; EM) were the materials used in this study. Specimens with the required dimensions for microtensile bond strength and flexural strength test were prepared and finished. The specimens were divided into two groups: control group that was stored in distilled water at 370C for 24 h (without thermo-mechanical load cycling) and test group (with thermo-mechanical load cycling). A total of 3,500 thermal cycles and 250,000 mechanical loading cycles were performed. Microtensile bond strength and flexural strength of each material were evaluated before and after thermo-mechanical load cycling. Moreover, additional micromorphological analysis such as those involving scanning electron microscopy and surface roughness of the etched ceramic bonded surfaces were performed for qualitative analysis. Data were analyzed using independent t-tests between the two glass ceramic groups, and paired t-test was used to detect significance within each group with and without thermo-mechanical load cycling.<br />Results: The effect of thermo-mechanical load cycling on microtensile bond strength was statistically significant for both types of glass ceramics (EM and SV) (P<.001) and the most frequent failure type was mode I (adhesive failure between cement and ceramic type) with pronounced effect on EM (66.67%) than on SV (40%). Regarding thermo-mechanical load cycling effect on flexural strength, there was statically significant difference (P<.001) only for EM.<br />Conclusions: SV glass ceramic showed higher bonding values than EM glass ceramic only after thermo-mechanical load cycling. However, it provides higher flexural strength values either before or after thermo-mechanical load cycling than EM glass ceramic.
aging,Bonding values,flexural strength,Reinforced glass ceramic
https://edj.journals.ekb.eg/article_76325.html
https://edj.journals.ekb.eg/article_76325_24fc1ee0c5ded2cce0335c4f9f7665c1.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
A COMPARISON OF THE ACCURACY OF THE DISTO-LINGUAL FLANGE ADAPTATION USING TWO DIFFERENT DENTURES BASE MATERIALS IN LOWER COMPLETE DENTURES: AN IN-VITRO STUDY
2795
2802
EN
Nora
Mohamed
Sheta
Lecturer, Department of Prosthodontics, Faculty of Dental Medicine, Cairo University.
10.21608/edj.2017.76327
Purpose: This study was conducted to compare the adaptation accuracy of distolingual flange of mandibular complete dentures fabricated by versacryl and soft acryl <br />Material and methods: 14 lower completely edentulous casts with bilateral distolingual undercut were duplicated from mandibular completely edentulous patient.14 Mandibular complete dentures were processed with Conventional heat cure acrylic resin denture base except the distolingual flange. Dentures were divided into two equal groups: Soft acryl Group at the distolingual flange and Versacryl group at the distolingual flange. The gap between the denture and the cast at the distolingual undercut was measured at three points (A,B,C)using Stereo microscope.<br />Result : The result of this invitro study revealed that median gap width value of soft acryl group (733.2) and IQR 224.65 to median gap width value of Versacryl group (1256.748)and IQR(1039.2) regardless of the location. The Versacryl group showed statistically significant higher median gap width value than soft acryl group with p value = 0.00<br />Conclusion : Within the limitation of this invitro study, the gap distance found when using versacryl in the disto lingual undercut, was greater than the gap distance found with the use of soft acrylic. Soft acryl as denture base showed more adaptation comparing to the versacryl as the distolingual flange of in lower complete denture.
Lower denture,adaptation. Undercut,flexible flange
https://edj.journals.ekb.eg/article_76327.html
https://edj.journals.ekb.eg/article_76327_b71e53f04e92524b38faa9a352b4841f.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
FRACTURE RESISTANCE, FINITE ELEMENT ANALYSIS AND WEIBULL RISK OF FAILURE FOR ENDODONTICALLY TREATED MOLARS RESTORED WITH LITHIUM DISILICATE AND HYBRID CERAMIC ENDOCROWNS WITH TWO PREPARATION DESIGNS
2803
2820
EN
Rania
A
Amin
Assistant Professor in Crowns and Bridges Department, Faculty of Dental Medicine, Al-Azhar University (Girls’
branch), Egypt
Mostafa
A
Abdellatif
Lecturer of Dental Materials Science, Biomaterials Department, Faculty of Oral and Dental Medicine, Future
University in Egypt, FUE
Heba
E.
Eltayeb
Lecturer of Dental Materials Science, Biomaterials Department, Faculty of Dental Medicine, Al-Azhar University
(Girls’ branch), Egypt
10.21608/edj.2017.76330
Objective: The present study aimed at evaluating the fracture resistance of endodontically treated molars restored using IPS e.max CAD (e.max CAD) and Enamic endocrowns using two preparations designs after thermomechanical fatigue.<br />Materials and methods: 40 intact mandibular molars were selected and endodontically treated following a standardized procedure. Molars were decapitated 3.5mm coronal to the cervical line then embedded in epoxy resin blocks. Samples received standardized preparations for endocrowns including the preparation of the pulp chamber, then they were divided into two groups; group 1 where No-Ferrule was included in the preparation and group 2 with 2.5mm Ferrule extracoronally. Each group was further divided into two subgroups according to the material used for constructing endocrowns; e.max CAD endocrowns and Vita Enamic endocrowns. Endocrowns were constructed using Cerec CAD/CAM machine. Constructed endocrowns were adhesively bonded to their respective teeth then subjected to a thermomechanical fatigue procedure (49N, 1.6Hz, 120,000cycle, 5o-55o C) in a chewing simulator. The fracture resistance of each sample was determined by subjecting the samples to a static compressive load until failure. Failure loads were recorded as an indication of fracture resistance. Stresses at failure were analyzed using finite element analysis (FEA) and failure probability percentage was evaluated using Weibull risk of failure. Data were collected, tabulated and statistically analyzed.<br />Results: For fracture resistance, the highest fracture load values were recorded with samples of Ferrule with e.max CAD endocrowns, followed by samples of No-Ferrule with e.max CAD endocrowns and then samples of Ferrule with Enamic endocrowns. The lowest fracture load values were recorded with samples of No-Ferrule with Enamic endocrowns. The magnitude of stresses generated in different parts of the samples as reveled by FEA generally followed a different order than in the fracture resistance. Weibull Risk of failure showed that samples of No-Ferrule with Enamic endocrowns had the highest failure probability especially under high loads. <br />Conclusions: Ferrule design would improve the fracture resistance of endodontically treated teeth especially when restored with lithium disilicate based (e.max CAD) endocrowns. Under low magnitude of forces, both materials would work safely with either design.
https://edj.journals.ekb.eg/article_76330.html
https://edj.journals.ekb.eg/article_76330_4633aa50720f6eb6118417e30fcb4f40.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
THE INFLUENCE OF INTER-IMPLANT DISTANCE ON BONE HEIGHT CHANGES FOR A THREE IMPLANT RETAINED MANDIBULAR TELESCOPIC OVERDENTURE
2821
2833
EN
Nouran
Abdel Nabi
Lecturer of Removable Prosthodontics. Cairo University
10.21608/edj.2017.76333
Introduction: Implant retained mandibular overdentures have improved patient satisfaction and quality of life for completely edentulous patients , that is why it has been the most successful treatment modality for the edentulous mandible. The optimum number of implants to retain an overdenture has been debatable, most studies have recommended installing two to four implants to retain an overdenture. Many authors have reported that three implant retained over denture will provide sufficient support and stability. Bars, studs, magnets, and telescopic coping are attachments to be used to retain mandibular overdentures, many factors should be considered during the selection of the most suitable attachment. Telescopic retainers have offered excellent retention with a splinting effect in addition to providing superior oral hygiene maintenance. One of the important criteria determining the success of an overdenture is the even distribution of stresses to the underlying implants as excessive loads may result in failure of the anchoring implants. Monitoring of bone height changes is therefore mandatory and is most commonly carried out by standardized peri-apical X- rays at different follow up intervals. The aim of this clinical trial is to investigate the effect of the inter-implant distance in a telescopic three implant retained overdenture on the amount of load transfer to the implants which is clinically interpreted by changes in bone height utilizing standardized peri-apical x rays.<br />Materials and methods: Fourteen completely edentoulous patients have been recruited from the outpatient clinic of the Removable Prosthodontic Department Cairo University. All recruited patients were seeking implant installation in the edentulous jaw to improve retention of their mandibular denture. Patients with contra-indication for implant placement were excluded from the study. All patients received three implants in the mandible in the canine region bilaterally and in the central incisor area, but the interimplant distance of the installed implants varied in the two groups of patients. In the first group of patients all implants were installed with an even interimplant distance of 40mm. While in the second group of patients an uneven distribution of implants with different interimplant distance, on the right side the implants in the canine area and central incisor region had an interimplant distance of 15mm, while on the left side the implant in the left canine region was installed at a 40mm from the implant at the central incisor area. Standardized peri-apical x rays were used to record changes in bone height for the three installed implants in the two groups of patients at the different follow up intervals; day of delivery, after 3 month follow up, after 6 month follow up and after 12 month follow up. <br />Results: In both groups of patients there has been a decrease in bone height for all implants after a 12 month follow up. In the first group of patients there was no statistically significant difference in the mean bone height changes between the three implants, but the implant in the mid line have shown the greatest changes in bone height followed by the implant in the left canine and the least was the implant in the right side. In the second group of patients there was no statistically significant difference between the two implants in the right side with a 15 mm interimplant distance, while a statistically significant difference in bone height changes was recorded for the implant on the left side with a 40mm interimplant distance showing the greatest changes in bone height followed by the implant in the mid line, and the least was the implant in the right canine. When comparing the mean bone height changes between the two groups of patients after a 12 month follow up, the second group of patients have shown a statistically significant decrease in bone height for all of the three implants, indicating more bone loss encountered in the second group of patients than in the first group.<br />Conclusion: The interimplant distance plays an important role in the transfer of stresses to the anchoring implants, as the interimplant distance increase so will the lever arm and eventually the moment falling on the implant will also increase, which will lead to bone height changes around the installed implants. All of the bone height changes in the present study after a 12 month follow up were within the physiological limit. Within limitations of this clinical trial it is recommended to install implants with an equal interimplant distance, and avoid implant installation with an increased interimplant distance. More researches with a larger sample size and longer follow ups are recommended to reach to definitive conclusions.
https://edj.journals.ekb.eg/article_76333.html
https://edj.journals.ekb.eg/article_76333_5628d028346383c20d7d65b821a794a8.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
EFFECT OF CONNECTOR SURFACE AREA AND TYPE OF CEMENT ON FRACTURE RESISTANCE OF FULL CONTOURED MONOLITHIC CAD CAM ZIRCONIA FIXED PARTIAL DENTURES
2835
2846
EN
Mohamed
Fattouh
Abdullah
Assistant Professor of Fixed Prosthodontics, Department of Fixed Prosthodontics, Faculty of Dentistry, Cairo
University, Giza, Egypt
Doaa
Abd ElAziz A.
Helal
Lecturer of Fixed Prosthodontics, Fixed Prosthodontics Department, Faculty of Dentistry, Beni Suef University,
Beni Suef , Egypt.
10.21608/edj.2017.76336
The aim of this study: was to investigate the influence of different connector surface areas on the fracture resistance of three and four units full contoured monolithic zirconia FPDs manufactured by CERCON machine and cemented by either zinc phosphate or resin cements. <br />Materials and methods: Sixty full contoured monolithic zirconia FPDs cementd on resin casts were divided into two main groups (30 FPDs each) according to the number of units (three and four units FPDs), each group was subdivided into three subgroups according to connector surface area dimensions (10FPDs each). Subgroup A1: Surface area of each connector didn’t exceed <br />24 mm2. , Subgroup A2: Surface area of each connector was greater than 24 mm2 and less than <br />35 mm2 and Subgroup A3: Surface area of each connector was more than 35 mm2. Each subgroup was further randomly divided into two (5FPDs each). division C1 : FPDs were cemented using zinc phosphate cement and division C2 : FPDs were cemented using dual cured resin cement (Variolink N). the specimens were stored in deionized water in an incubator (QWJ500; Queue Systems Inc. USA) maintained at oral temperature (37°C) for and removed 24 hours before mechanical testing. Specimens were loaded in universal testing machine until failures were observed. The obtained data of fracture resistances were statistically analyzed. <br />Results: showed that for all subgroups, by increasing the connector surface area a statistically significant increase in the fracture resistance was observed, whether using resin cement or zinc phosphate cements. For three units FPDs, using adhesive resin cement produced higher fracture resistance values than using zinc phosphate cements, that were statistically non-significant for subgroupsA1,A2 while it was statistically significant for subgroup A3. (at p-value < 0.05). For four units FPDs, using adhesive resin cement produced higher fracture resistance values than using zinc phosphate cements that were statistically non-significant for subgroup A1, while they were statistically significant for subgroups A2and A3. (at p-value < 0.05). using Zinc phosphate cements with three units FPDs produced statistically significant higher values than with four units FPDs <br />Using resin cements with three units FPDs produced statistically significant higher values than with four units FPDsfor only subgroup A3. While the difference was not statistically significant for subgroup A1 and A2. conclusions: it was found that the fracture resistance of the full contoured three and four units FPDs made using monolithic zirconia is affected by the connector dimension , span length and the used cement. By increasing the connector surface area, the fracture resistance values increased significantly with both cements. Generally, For all tested subgroups, three units monolithic zirconia FPDs have higher fracture resistance values than four units FPDs. Using resin cement produced higher values of fracture resistance than using zinc phosphate cement.
Full contoured zirconia,Monolithic Zirconia,Resin and zinc phosphate cements,CERCON,connector surface area,Fracture resistance
https://edj.journals.ekb.eg/article_76336.html
https://edj.journals.ekb.eg/article_76336_7fcd4343fe214747153a6e99a73a5a5f.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
COMPARATIVE STUDY OF THREE DIFFERENT TECHNIQUES FOR BROKEN INSTRUMENT REMOVAL
2847
2854
EN
Mennattullah
Mohsen
Hafez
Assistant Lecturer, Department of Endodontics, Misr International University.
Ahmed
Mostafa
Ghobashy
Lecturer, Department of Endodontics, Misr International University.
Ehab
Elsaied
Hassanein
Professor, Department of Endodontics, Misr International University.
10.21608/edj.2017.76337
The purpose was to evaluate three systems for broken instrument retrieval (Ultrasonic, Instrument Retrieval System “IRS”, and Microtube + Cyanoacrylate Adhesive). Cross-sectional area, time, and perforation incidences were recorded. A total of 60 extracted molar teeth were used. Teeth were placed in a cast compound arch shaped mold to facilitate handling. Teeth were divided into two groups according to type of motion used Group I: Reciprocating motion (n=30) <br />Group II: continuous rotation motion (n=30), and three subgroups according to the retrieval instrument used. Concerning retrieval time, Ultrasonics showed least time needed for retrieval in comparison to IRS and Microtubes. Ultrasonics can be used as universal retrieval systems for canal obstructions.
IRS,microtube,Retrieval,ultrasonics,Time
https://edj.journals.ekb.eg/article_76337.html
https://edj.journals.ekb.eg/article_76337_ff294f0463d0d9fdadb23c8d22b919c9.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
COMPARISON OF TWO DENTURE ADHESIVES ON MANDIBULAR COMPLETE DENTURE RETENTION AND PATIENT SATISFACTION
2855
2861
EN
Amr
A.
Rady
Lecturer of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University.
10.21608/edj.2017.76339
Introduction: One of the main problems faced by conventional complete denture wearers is the retention and stability of their dentures during function. To overcome this problem, many attempts have been tried including invasive surgical techniques, implants, suction systems and the least offensive denture adhesives. Dentists have prescribed a range of adhesives of highly varied composition and efficacy. <br />Purpose: The present clinical study evaluates the effectiveness of two adhesives in improving complete denture retention as well as patients’ satisfaction.<br />Material and Methods: An in vivo clinical study is made of 20 patients with complete mandibular dentures to evaluate the retention provided by two commercial complete denture adhesives (Poligrip and Fittydent). A digital force meter scale was used to measure retention strength (in grams). Patients were asked to answer a simple questionnaire before and after using the tested adhesives regarding their acceptance to the retention and chewing ability.<br />Results: The results obtained indicate that retention is enhanced using both adhesives, no significant difference was detected between the two adhesives and patients approved the enhancement of their denture retention and chewing ability in presence of both adhesives.<br />Conclusion: within the limitation of this study it can be concluded that denture adhesives efficiently improve the denture retention.
https://edj.journals.ekb.eg/article_76339.html
https://edj.journals.ekb.eg/article_76339_b57faa8feb355a787245df16c6bc8b26.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
THE INFLUENCE OF BORDER MOLDING ON RETENTION AND TIME OF COMPLETE DENTURE IMPRESSION
2863
2869
EN
Amr
A
Rady
Lecturer of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University.
Nouran
A
El Naby
Lecturer of Removable Prosthodontics, Faculty of Oral and Dental Medicine, Cairo University.
10.21608/edj.2017.76340
Background: Maintenance of contact of the denture border with the adjacent vestibular tissues during rest as well as in function is an important criterion of denture success that depends on proper border tracing. Different border moulding materials are available for achievement of that goal although many clinicians deliver excellent denture without border trimming procedure. <br />The aim of this study is firstly to evaluate the time needed to perform sectional border molding with two different border tracing materials and to compare the retention of the finished impressions with non-border molded impression. <br />Material and method: Twelve completely edentulous patients were selected and signed consents to evaluate the retention provided by three different final impression techniques (sectional border moulding of a special tray with low fusing compound and final wash with medium bodied silicone material, sectional border tracing of a special tray with putty elastomeric impression material followed by a final wash with medium bodied silicone material and third impression with special tray without border moulding). A stop watch was used to record the time needed to finish the border moulding in the first two impression technique, then a digital force meter was used to measure retention strength provided by each technique. <br />Results: The statistical analysis showed extremely significant difference between the time needed to finish border moulding with putty silicone material and that with the low fusing compound. Moreover, no significant difference was detected between the three impressions techniques. <br />Conclusion: Putty silicone material allows faster, easier and effective border moulding procedure rather than low fusing compound. Medium body silicone material in special tray without border moulding yielded highly retentive impression comparable to those with different border tracing materials.
https://edj.journals.ekb.eg/article_76340.html
https://edj.journals.ekb.eg/article_76340_37e347028fd1998d5789fedc505bdbdd.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
DIGITAL TECHNOLOGY IN COMPLETE DENTURE PROSTHODONTICS: A REVIEW OF LITERATURE
2871
2885
EN
Mohamed
H.
Abdelnabi
Associate Professor, Oral and Maxillofacial Prosthodontic Department, Faculty of Dentistry, King Abdulaziz
University, Jeddah, Saudi Arabia; Removable Prosthodontic Department, Faculty of Dentistry, Minia University,
Egypt.
Amal
A.
Swelem
Associate Professor, Oral and Maxillofacial Prosthodontic Department, Faculty of Dentistry, King Abdulaziz
University, Jeddah, Saudi Arabia; Removable Prosthodontic Department, Faculty of Oral and Dental Medicine,
Cairo University, Egypt.
amalswelem@gmail.com
10.21608/edj.2017.76341
Background: Computer-aided design and computer-aided manufacturing (CAD/CAM) technology has expanded to embrace implant, maxillofacial and removable prosthodontics including the fabrication of complete dentures. However, despite that the implementation of computer-aided technology with edentulous patients seemed to improve and simplify complete denture treatment as it significantly reduced the number of patient visits, yet still a limited number of reports described its use for complete denture fabrication<br />Objective: This literature review will cast light on digital technology and its implementation in complete denture prosthodontics including its advantages, limitations, techniques and will present the articles that reported or investigated this topic and their outcomes including clinical or patient-based outcomes<br />Materials and methods: An independent electronic search of the English language literature was conducted by 2 investigators (authors), in bibliographic database MEDLINE, EMBASE, the Cochrane Library and Google up to March 2017 using certain key words. The electronic search was conducted in 3 stages in a systematic order. Stage 1, involved acquiring a record of titles from the electronic databases, which was then independently analysed by each investigator to extract relevant titles based on the predetermined inclusion criteria. The investigators independently applied the exclusion criteria, and any inconsistency was resolved by discussion. In uncertainty situations, the disputed article was included in the second (abstract) stage for contemplation. Stage 2 involved screening the abstracts of all selected titles by both investigators separately. Once more, any disagreement between the investigators was discussed, and, in uncertain situations, the abstract was included in the third and last stage of full-text analysis. At stage 3, all full text articles that were included were studied by the two investigators. This was followed by applying the final exclusion criteria and reviewing the final list of articles thoroughly and in depth to extract all relevant qualitative and quantitative data. <br />Results: The review included a total of 20 articles. 2 studies described techniques for digital arrangement of denture teeth, 13 studies described techniques for digital fabrication of digital complete dentures either using rapid prototyping technology or computerized numerical control milling. The other 5 articles were clinical studies that assessed the clinical and patient-based outcomes of digitally-fabricated dentures.<br />Conclusions: Digitally fabricated dentures can be an effective and time-efficient option for completely edentulous patients with favourable clinical and patient-centered outcomes. They are preferred by clinicians and patients as they significantly reduced clinical time and number of appointments, improved retention as well as digital archivability and hence reproducibility. However, dental literature lacks short-term and long term prospective clinical studies in this field to be able to reach definitive conclusions.
https://edj.journals.ekb.eg/article_76341.html
https://edj.journals.ekb.eg/article_76341_3d24c5dbf27129f6371111bf30ab8330.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
DEBRIS EXTRUSION FROM SEVERELY CURVED ROOT CANALS AFTER INSTRUMENTATION WITH WAVEONE GOLD OR ONESHAPE SINGLE FILES
2887
2893
EN
Hend
Mahmoud
Abou El Nasr
Department of Endodontics, Faculty of Oral and Dental Medicine, Cairo University, Egypt
Shaimaa
Ismail
Gawdat
Department of Endodontics, Faculty of Oral and Dental Medicine, Cairo University, Egypt
10.21608/edj.2017.76342
Aim: The aim of this study was to assess the effect of degree of curvature on extrusion of debris from root canals; and to compare the amount of extruded debris after instrumentation with WaveOne Gold reciprocating (WOG; Dentsply Maillefer, Ballaigues, Switzerland) and OneShape rotating (OS; MicroMega, Besançon, France) single file systems.<br />Materials and methods: Sixty mesiobuccal canals were assigned to 2 equal groups according to the degree of curvature, whether severe (25-40°) or moderate (10-15°) as measured using Schneider method. The canals in each group were further subdivided into 2 subgroups (n=15) according to the instrument used for preparation; WaveOne Gold (WOG) or OneShape (OS) files. The extruded debris was collected in preweighed glass vials. Data were statistically analyzed using One-way ANOVA and Tukey’s post-hoc tests.<br />Results: The least amounts of debris were obtained with WaveOne Gold instruments in both curvatures, with no significant difference between them (P > 0.05). Larger amounts of debris occurred with OneShape instruments in severely curved canals; but this difference was of no statistical significance. Statistically significant differences were recorded only when OneShape instruments were used in moderately curved canals. <br />Conclusions: Debris extrusion occurs independent of the motion or design of the instrument. However, moderate root canal curvatures allowed more extrusion of debris than severe curves. WaveOne Gold results were not affected by the degree of canal curvature; and outperformed OneShape instruments in both types of curves.
Debris extrusion,severe canal curvature,OneShape,WaveOne Gold,reciprocation
https://edj.journals.ekb.eg/article_76342.html
https://edj.journals.ekb.eg/article_76342_3300afa2ec16975133d1d7199fbdc33f.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
THE EFFECT OF EGG SHELL VERSUS FLUORIDE VARNISH ON REMINERALIZATION OF EARLY ENAMEL DEMINERALIZED LESIONS
2895
2904
EN
Hala
M.
Fares
Associate Professor, Department of Operative Dentistry, Faculty of Oral and Dental Surgery, Misr University for
Science and Technology. Egypt.
Muhammad
A
Samman
Associate Professor, Dental Biomaterials, Faculty of Dental Medicine, Al Azhar University Cairo, Egypt
Ola
Barakat
Associate Professor, Operative Dentistry, Faculty of Oral and Dental Surgery, Misr University for Science and
Technology, Cairo, Egypt
10.21608/edj.2017.76343
Twenty freshly extracted non-carious human molars were used. The mineral content of all teeth was initially assessed using EDX. Teeth were then divided randomly into two groups each containing ten samples. All teeth were placed in demineralizing agent after which one group (I) was remineralized using egg shell solution while the other group (II) was remineralized using fluoride varnish (Proshield, President dental Germany). This process was held in a pH cycling mode.Regarding mineral content specimens of both groups were initially assessed (base line measurements), then reassessed directly after demineralization, three days from remineralization and at the end of seven days remineralization period. Results were as follow : Regarding Ca wt % and comparing the two groups there was no statistical significance at base line measurements, after demineralization and after three days from remineralization. Meanwhile after seven days remineralization group (I) demonstrated statistically significant lower mean Ca atomic wt % than group (II). Regarding phosphorus atomic wt % for measurements of base line, after demineralization and after remineralization there was no statistical significance between the two groups. Regarding the effect of time for Ca wt % and after seven days group (I) showed non statistically significant decrease in Ca wt % compared to that at base line, while group (II) showed non statistically significant difference from the value measured at base line. For the P wt % and after seven days both groups demonstrated non statistically significant lower mean values compared to base line data.
Remineralization – egg shell – fluoride varnish Introduction
https://edj.journals.ekb.eg/article_76343.html
https://edj.journals.ekb.eg/article_76343_0358c216868ee16805a52deb9143c406.pdf
The Egyptian Dental Association (EDA)
Egyptian Dental Journal
0070-9484
2090-2360
63
Issue 3 - July (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)
2017
07
01
BONDING ABILITY OF DIFFERENT LINERS TO BULK-FILL RESIN COMPOSITE USING SILANE-CONTAINING ADHESIVE
2905
2913
EN
Muhammad
Samman
Assistant Professor, Dental Biomaterials Faculty of Dental Medicine, Al-Azhar University Cairo, Egypt.
Ola
Barakat
Associate Professor, Operative Dentistry, Faculty of Oral and Dental Surgery, Misr University for Science and
Technology, Cairo, Egypt
Hala
Fares
Associate Professor, Operative Dentistry, Faculty of Oral and Dental Surgery, Misr University for Science and Technology, Cairo, Egypt
10.21608/edj.2017.76344
Aims: To compare and evaluate the bonding ability of bulk-fill resin composite (RC) to four different liners: Biodentine (BD), TheraCal (TLC) - a novel resin-modified calcium silicate cement, resin-modified glass ionomer cement (RMGIC) and conventional glass ionomer cement (GIC) using a universal silane-containing adhesive and characterizing their failure modes.<br />Materials and Methods: Forty extracted intact human premolars with occlusal cavity (4-mm diameter and 2-mm height) were mounted in acrylic blocks and divided into four groups of (n=10 samples) each based on the liner used as group I; (BD), group II; (TLC), group III; (RMGIC) and Group IV; (GIC). Bulk-fill composite buildup of 3 mm diameter and 5 mm height was then bonded to each sample using universal adhesive. Shear bond strength (SBS) analysis was performed using materials testing machine at a cross-head speed of 0.5 mm/min. <br />Statistical Analysis: Statistical analysis was performed with one-way analysis of variance (ANOVA) and Tukey’s post hoc test for numerical data while chi square test for categorical one. <br />Results: One-way analysis with ANOVA revealed significant difference in bond strength values between the different groups (p<0.001). The observed modes of failure were predominantly cohesive in Biodentine, TheraCal and GIC groups while RMGIC showed majority of mixed and minority adhesive failures.<br />Conclusions: Biodentine demonstrated lower bond strength values when immediately bonded to bulk-fill resin composite compared with RMGIC, TheraCal and GIC groups
https://edj.journals.ekb.eg/article_76344.html
https://edj.journals.ekb.eg/article_76344_66dd046c3632ff2db048ded6e3186e7a.pdf