The Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Color stability of ceramic occlusal veneer with different translucency, designs and resin cement curing modes using “accelerated Artificial Aging”3673747155710.21608/edj.2015.71557ENAdel A.El BadawyAssistant professor of Crown & Bridge, Faculty of Dentistry, Al Azhar UniversityMohammed H.Abd El AzizAssistant professor of Crown & Bridge, Faculty of Dentistry, Al Azhar UniversityElsayed A.OmarAssistant professor of Crown & Bridge, Faculty of Dentistry, Al Azhar UniversityJournal Article20200217Statement of problem: Clinically, Occlusal veneers is thin resin bonded restoration making color change liable to occur. <br />Purpose: The aim of the present study was directed to evaluate occlusal veneer color stability with different ceramic materials translucency, axial wall convergence angle and resin cement curing mode systems using “accelerated Artificial Aging”. <br />Materials and Methods: Eighty maxillary first molars were carefully selected and were divided into two main divisions (12 and 22 degree of convergence angle) (n=40), then each main division was divided into two groups (n=20) according to ceramic translucency (high and low translucency [HT and LT], finally, each group was subdivided into two subgroups (n=10) according to the type of used resin cement (light and dual cure). Occlusal surfaces were reduced leaving 5 millimeters. Shoulder finish line was made with 1mm thickness and 1.5 mm height. The occlusal surface was made using the Cerec scanner software’s design tools. The occlusal veneer specimens were cemented using light and dual cured resin cement. The initial color measurements were taken followed by accelerated aging process and finally, second color measurement was taken. <br />Results: The highest mean value of color variation (ΔE) was recorded at 12 ° convergence angle in the high translucent (HT) samples that have been cemented by light cured resin cement (2.01 ± 0.16), while the lowest mean value of color variation (ΔE) was recorded at 22 ° convergence angle in the low translucent (LT) samples that have been cemented by dual cured resin cement <br />(1.28 ± 0.11).<br />Conclusions: Color stability of occlusal veneer is apparently affected by ceramic translucency, degree of preparation convergence angle and curing mode of resin cement.https://edj.journals.ekb.eg/article_71557_6532160baf2edf1ecd7023ef39ac518a.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Fracture Resistance of Endodontically Treated premolar Teeth Restored With CAD/CAM Lithium Disilicate Endocrowns and H-shaped post: In Vitro Study3753807156110.21608/edj.2015.71561ENAlaa Abdelzaher AbdelhamidOmaraB.S.C, BDS, Faculty of Oral and Dental Medicine, Cairo UniversityJournal Article20200217Aim: This study was conducted to compare the fracture resistance of lithium disilicate endocrowns with circular post and endocrowns with H-shaped short post when bonded to endodontically treated premolar teeth. <br />Materials and Methods: A twenty two extracted single rooted premolars (specimens), were divided into two equal groups (11 specimens in each group). Group H : restored with endocrowns with H- shaped post. Group C : restored with endocrowns with circular post. Teeth were scanned with DOF scanner and restorations were designed with EXOCAD software. All restorations were milled with imes-icore machine. The endocrowns were cemented on their corresponding teeth using BisCem (Bisco Inc., Schaumburg, IL, USA) dual-cure adhesive resin cement following total etch technique protocol. All samples were subjected to fracture resistance testing using universal testing machine. After facture testing, fracture patterns and failure mode of all samples were examined visually and photographically by digital camera. Data were collected and statistically analysed. <br />Results: Independent t test revealed that endocrowns with H-shaped post (Group H) showed higher fracture resistance values (1374.6 ±313 N), compared with endocrowns with circular post (Group C) (1107.9 ± 205 N). Chi square test showed no statistically significant difference between groups in mode of failure. <br />Conclusion : Lithium disilicate endocrowns with H-shaped post provide promising design in premolar region. Design of post of endocrown has no effect on mode of failure.https://edj.journals.ekb.eg/article_71561_7f333171aff626aba5610bcf18931202.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Comparative Study of Cyclic Fatigue Resistance of Protaper Gold, OneShape, and TF Files3813857156910.21608/edj.2015.71569ENShady AliHusseinLecturer of Endondontics, Ain-Shams UniversityAmr AhmedBayoumiLecturer of Endondontics, Misr International UniversityJournal Article20200217Aim: The purpose of this study was to compare the resistance to cyclic fatigue of three nickel-titanium (NiTi) endodontic instruments from Protaper Gold (PTG), OneShape (OS), and Twisted files (TF). <br />Methodology: A total of 45 nickel-titanium instruments were tested and divided into 3 experimental groups (n = 15): group 1, Protaper Gold (F2 25/.08); group 2, OneShape (25/.06) file; and group 3, Twisted file (25/.06). The testing device was specially designed for this experiment. The time and cycles to failure were calculated. The data were compared for differences by using 2-way analysis of variance (p < 0.05). <br />Results: Statistical analysis revealed that PTG showed the statistically significantly highest mean cyclic fatigue value, while TF showed statistically significantly lower mean cyclic fatigue value. OS system showed the statistically significantly lowest mean cyclic fatigue value. <br />Conclusions: ProTaper Gold files demonstrated significantly higher cyclic fatigue resistance than OneShape and Twisted files, while OneShape files revealed the lowest cyclic fatigue resistance. The enhanced alloy properties of ProTaper Gold may be the main reason for this difference.https://edj.journals.ekb.eg/article_71569_b9b315cb97f801f6c8146b27b561e30e.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101IN VITRO EVALUATION OF THE Effect of different irrigation solutions on the apical sealing ability of three root canal sealers when the continuous wave obturation technique was used3873977271410.21608/edj.2019.72714ENMohamed AM.El SayedAssociate Professor, Endodontic Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt;
Restorative Dentistry Department, College of Dentistry, Ajman University, Ajman, UAE.Shakeri M.FathiehGeneral Practitioner, Restorative Dentistry Department, College of Dentistry, Ajman University, Ajman, UAEJournal Article20200222Aim: The aim of this study was to compare the effect of three irrigating solutions on the apical sealing ability of three endodontic sealers when the continuous wave obturation technique was used.<br />Materials and Methods: 100 maxillary central incisors were decoronated and roots were divided into three experimental groups (n=30 each) according to the type of irrigating solution, and two control groups (n=5 each). Each experimental group was divided equally into three subgroups according to the type of obturation system. All canals were instrumented using ProTaper Universal rotary system and irrigated with 3% sodium hypochlorite (Group 1), 2% chlorohexidine (Group 2), and 3% hydrogen peroxide (Group 3), followed by 17% EDTA and distilled water. Continuous wave technique was used to obturate root canals with the following combinations: MTA Fillapex/Gutta-percha (Subgroup A), AH Plus/Gutta-percha (Subgroup B) and Realseal SE/Realseal <br />(Subgroup C). The apical microleakage was assessed using linear dye penetration method and the data were statistically analyzed. <br />Results: Significant differences were found between all groups (P<0.05). All root canal sealers after irrigation with 3% hydrogen peroxide showed the lowest amounts of apical leakage. Samples irrigated with 3% sodium hypochlorite or 2% chlorohexidine showed the highest amounts of apical leakage. <br />Conclusions: The type of irrigating solution could affect the apical sealing ability of experimental sealers when used with the continuous wave obturation technique. Root canal irrigation with 3% hydrogen peroxide + 17% EDTA increased the sealing ability of all root canal sealers. Root canal irrigation with 3% sodium hypochlorite 2% chlorohexidine + 17% EDTA decreased the sealing ability of all root canal sealers.https://edj.journals.ekb.eg/article_72714_3b57830f8f8e5e256a1e5b14cbd79669.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Fluoride Release and Recharge Behavior of Bioactive Glass Ionomer Cements using Ion Chromatography3994067271510.21608/edj.2019.72715ENAsmaa MohamedAbdallahLecturer, Operative Dentistry Department, Faculty of Dentistry, Mansoura University, Egypt.Tamer MohamedElshehawyLecturer, Operative Dentistry Department, Faculty of Dentistry, Mansoura University, Egypt.Hamada MohamedIbrahimLecturer, Chemistry Department, Faculty of Science, Fayoum University, Egypt.Journal Article20200222Objective: To evaluate fluoride release and uptake behaviors of the new bioactive resin modified glass ionomer cement (RMGIC) (activa bioactive glass ionomer) compared to conventional glass ionomer cement(CGIC) (Fuji IX GP). <br />Material and Methods: Forty specimens were prepared (10 mm x 2 mm) from Fuji IX GP glass ionomer and Activa Bioactive RMGI according to manufacturer’s instructions. The specimens stored in deionized water and fluoride release were assessed daily in the first week then weekly till the third week using ion chromatography. The specimens of each material were divided into two equal subgroups according to the recharging agents used ; either0.05% mouth wash (226 ppm sodium fluoride, G.U.M, Sunstar, Germany, GmbH) or 5% sodium fluoride varnish (22.600ppm fluoride, enamel pro varnish Premier Dental, Plymouth Meeting, PA,19462,USA). Fluoride release after recharge was measured and recorded daily for a total of 5 days. Data were analyzed by Two way ANOVA and Duncans test (α = 0.05) using the SPSS software program. <br />Results: CGIC release higher amount of fluoride than RMGIC. Professionally applied fluoride varnish showed better recharging ability than home care fluoride mouth wash and CGIC had greater recharge ability than new RMGIC.https://edj.journals.ekb.eg/article_72715_cb7402830b81d629b747b0d777947f6c.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Microhardness testing of resin cement versus sonic bulk fill resin composite material for cementation of CAD/CAM composite block with different thickness4074167271610.21608/edj.2019.72716ENAhmedElzoheiryAss. Professor of Conservative Dentistry, Faculty of Dentistry, Cairo UniversityAmirHafezLecturer of Conservative Dentistry, Faculty of Dentistry, Cairo UniversityHaithamAmrLecturer of Fixed Prosthodontic, Faculty of Dentistry, Fayoum UniversityJournal Article20200222Objective: evaluate the microhardness and depth of cure of sonic bulk fill resin composite material for cementation of CAD/CAM composite block with different thicknesses versus the traditionally used dual cured resin cement by assessing microhardness at the top and bottom and calculating bottom/top ratio to determine the depth of cure.<br />Materials and methods: CAD/CAM resin composite blocks (Grandio) restorative materials were used in the present study. For cementation options, two resin materials were selected: SonicFill 2 bulk fill resin composite (Kerr) and Dual-link universal Resin cement (Bisco). Four sections were prepared from each CAD/CAM blocks thickness of 1 mm, 1.5 mm, 2 mm and 3 mm respectively. Sectioned specimens of each CAD/CAM blocks were then divided according to their thickness into three groups (n=5).Portions of each composite cement were placed on a 1-mm thick transparent glass slide and squeezed to a 100µm film thickness Each specimen was covered with one of the CAD–CAM composite block slabs or left uncovered (control) and then light-cured for 40 sec that was positioned perpendicularly on top and in direct contact with the CAD–CAM slabs or the top glass (control).Micro-hardness was obtained for the top and bottom surface of specimens. The mean microhardness values and hardness ratio % of the specimens were calculated and tabulated. Microhardness measurements were performed twice; one immediately and after 24 hours. Statistical analysis was performed. Significance of the difference within the same group was evaluated using one way analysis of variance (ANOVA) test, followed by Tukey’s post hoc test when ANOVA indicated a significant difference. T test was used to compare between both groups. The level of significance was set at P < 0.05. <br />Results: Immediately, in control, a higher mean value was recorded in Sonicfill group, with a statistically significant difference (p=0.011). In 1 mm, 1.5 mm, 2mm, a higher mean value was recorded in SonicFill 2 group, with a statistically significant difference (p=0.003, p=0.00, p=0.00 respectively). In 3 mm resin cement recorded a mean value of 0.495±0.012.After 24 hours, in control, a higher mean value was recorded in resin cement group, with no statistically significant difference (p=0.44). In 1 mm, 1.5 mm, a higher mean value was recorded in SonicFill 2 group, with no statistically significant difference (p=0.55, p=0.356 respectively). In 2 mm, resin cement recorded a significantly higher mean value (p=0.00). In 3 mm, resin cement recorded a mean value of 0.876±0.008<br />Conclusions: Under the limitation of the current study it could be concluded that bulk fill light cured resin composite as new trend in cementation procedure can be efficiently cured through CAD/CAM composite blocks with thickness not more than 1.5mm. Indeed, dual curable resin cement remains convenient for cementation of thicker indirect esthetic restoration.https://edj.journals.ekb.eg/article_72716_6f68686d5cb605d4aa2b826661104930.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Acidic Drinks on Color Stability of Different Direct Bulk-Fill Resin Composite Restorations4174267271710.21608/edj.2019.72717ENNadia M.ZaghloulAssistant Professor, Department of Operative Dentistry, Faculty of Dentistry, Mansoura University, Mansoura,
Egypt.Ashraf I.AliAssistant Professor, Department of Operative Dentistry, Faculty of Dentistry, Mansoura University, Mansoura,
Egypt.Journal Article20200222Introduction: Although resin composite restoration is now considered one of the most commonly used esthetic restoratives, color stability of restorations is the major demand for a successful and durable restoration. However acidic drinks have a discoloring effect on it<br />Aim of the study: This study aimed to evaluate the effect of acidic drinks on color stability of different direct Bulk-Fill Resin composite restorations.<br />Materials and methods: A total of 90 standardized disc shaped specimens were constructed, 30 from each restorative material (n=30), Filtek bulk-fill Posterior Restorative, TetricEvoCeram bulk-fill, and SonicFill resin composites using a customized split Teflon mold, with an internal space of 10mm diameter and 2mm thickness. Each specimen was photo-cured for 20 seconds, using a LED curing unite. Specimens of each restorative material were divided into three subgroups according to storage media used to store in (n=10); orange juice, Coca cola and artificial saliva. Color measurements were recorded for all specimens using Spectrophotometer before and after storage for 48 hour in the media. Finally, the values of ΔE were submitted to statistical analysis.<br />Results: Coca Cola caused the highest degree of discoloration of the resin composites, to be followed by Orange juice with the least color changes were noticed with storage in the Artificial saliva (p <0.0001) . Regarding to the bulk-fill resin composites, Filtek Posterior revealed the lowest levels of color change while the highest levels of discoloration were noticed with SonicFill bulk-fill resin composite, regardless the type of storage media (p > 0.05).<br />Conclusion: Bulk-fill resin composites, investigated in this study, showed less color stability than incremental resin composites. Acidic drinks have deteriorating effects on color of resin composite restorations.https://edj.journals.ekb.eg/article_72717_a5c7e9575848886f1c115e07b6f712b4.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Does a Low-shrink Resin Composite Induce Less Stress at the Adhesive/Dentin Interface in High C-factor Cavities?4274387271810.21608/edj.2019.72718ENNadia M.ZaghloulAssistant Professor, Department of Operative Dentistry, Faculty of Dentistry, Mansoura UniversityJournal Article20200222Objective: The aim of this in vitro study to compare µTBS of two low shrink, TCD- based and dimer acid-based and one flowable SDR-based bulk-fill, resin composites; on the bottom of high C-factor cavities. <br />Materials & methods: Thirty extracted noncarious human mandibular molars were used in the study. The occlusal enamel, in each tooth, was cut parallel to the occlusal surface, to expose a flat dentin surface. The cut teeth were randomly divided into two main groups (n=15), depending on the preparation of dentin i.e., group I: high C-factor occlusal class I cavity, and group II: flat dentin surface at the same depth of the cavity floor. Single Bond Universal adhesive was used to bond the resin composites to dentin in the two groups. Teeth in each group were further subdivided into three subgroups (n=5) according to the restorative materials used. In subgroup a: Surfil SDR flow, bulk-fill flowable resin composite. In subgroup b, TCD-DI-HEA based, Charisma Topaz, nano-hybrid resin composite. In subgroup c, DDCDMA based, N’Durance, nano-hybrid resin composite. All the samples were subjected to 5000 cycle, thermocycling. Each specimen was sectioned longitudinally in both mesio-distal and bucco-lingual directions to obtain four beams per each sample. A total of 20 sticks were collected from each subgroup and subjected to µTBS evaluation using universal testing machine and the results were then subjected to statistical analysis. The fractured surfaces were inspected under a stereomicroscope to determine the failure modes. <br />Results: The collected data were subjected to two way AOVA, followed by Tuky’s post hoc test. Dentin preparation factor afforded insignificant higher µTBS values with samples prepared in flat dentin surface compared to Samples with high C-factor class I cavities, when TCD- based, restorative material was used. DDCDMA based, ND, nanohybrid and SDR-based restorative material resulted in significant increase in the µTBS when applied to the flat dentin surfaces in comparison with the high C-factor class I cavities. The three restorative materials were arranged in a descending order from TCD- based, DDCDMA based, followed by SDR resin, with no significant difference, when applied to the flat dentin surfaces. Yet, with high C-factor class I cavity restorations, µTBS in SDR-based resin revealed the lowest significant values. Most of the failure modes are adhesive in nature. <br />Conclusions: Under the conditions of the present study, it might be concluded that TCD-based low-shrink resin composite investigated in this study perform well, in terms of compensation of polymerization shrinkage at the restoration/dentin interface and µTBS in high C-factor cavities. Conversely, the investigated Dimer acid-based and low-viscosity bulk-fill material based on SDR technology demonstrated unfavorable performance in high C-factor cavities.https://edj.journals.ekb.eg/article_72718_f1851d785210c68dc8fcab86a7dfbefa.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Root Canal Geometry Versus Different Coronal Restorations on the Strength of Endodontically Treated Teeth4394437271910.21608/edj.2019.72719ENShady AliHusseinLecturer at Endodontic Department, Faculty of Dentistry Ain Shams UniversityAhmed A.LaithyLecturer at Department of operative Dentistry, Faculty of Dentistry Ain Shams UniversityJournal Article20200222This study aimed to evaluate the combined effect of fiber post in different Root canal tapers. Sixty lower first premolar human extracted teeth had been used in this study, teeth were randomly divided into 3 equal groups (n=20). Group I; where cleaning and shaping was done using Twisted File (TF) #25 taper 0.04. Group II; where cleaning and shaping was done using Twisted File (TF) #25 taper 0.06. Group III; where cleaning and shaping was done using Twisted File (TF) #25 taper 0.08. Each main group was randomly subdivided into 2 equal subgroups (10 each) according to the coronal restoration type. Subgroup A; where coronal cavities were filled with Composite core material Multicore Flow (Ivoclar Vivadent, Schaan, Liechtenstein) (MCF), Subgroup B; where the coronal cavities were restored with fiber reinforced composite posts (FRC) and MCF. The fracture resistance of all groups had been evaluated & analyzed using Two-Way ANOVA. Results showed that 0.08 taper had a significant negative effect on the fracture resistance of teeth with and without post than 0.04 taper while other variants had no any statistically significant effect on the fracture resistance of the tested samples. It has been concluded that, under limitations of this study, the degree of taper of the root canal preparation only affects mechanical properties of the tooth when it increases more than 0.06 taper, while wether a post is used or not is of no use in class I conservative access cavity preparation of lower first premolar teeth. https://edj.journals.ekb.eg/article_72719_258a4badd7acb3e8a72dfbc591e0b16b.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of different fixed detachable implant supported prosthesis materials on the stresses induced on the supporting structures4454527272010.21608/edj.2019.72720ENM. ShadyNabhanLecturer of Removable Prosthodontics, Faculty of Dentistry Ain Shams UniversityJournal Article20200222<span style="text-decoration: underline;"></span>
Objectives: This study was conducted to evaluate the effect of different implant supported fixed detachable prosthesis materials (chrome cobalt-acrylic and BioHPP (Bio-High Performance Polyether)) on the stresses induced on the supporting structures.<br />Materials and methods: A maxillary completely edentulous resin cast was 3d printed with four implant sites (two straight anterior implants and two tilted posterior implants), mucosal space for mucosa simulation and vertical slots for strain gauges which were 1mm distal to the two distal implants. Four implant analogues were placed in their sites. Multiunit abutments were secured to the implants, then fixed detachable prostheses were fabricated. In this study two models were conducted: Group (A): Complete implant supported chrome cobalt-acrylic fixed detachable prosthesis. Group (B): Complete implant supported BioHPP fixed detachable prosthesis. Strain gauges were supplied with fully encapsulated grids and attached wires. Micro strains were recorded at each site of the strain gauges with enough time elapsed between each testing. The applied load started from 0 up to 100N. T test was used for comparison between the groups, at a significance level of <br />P ≤0.05. <br />Results: Group A (chrome cobalt- acrylic prosthesis) showed higher induced stresses on supporting structures compared to group B (BioHPP) during bilateral, unilateral, and oblique loading. Independent T test showed statistically significant difference between the studied groups, P value was <0.05.<br />Conclusion: Unilateral loading was more traumatic to the implants as compared to bilateral loading. BioHPP prosthesis has damping effect as it transferred less stresses to the supporting structures compared to chrome cobalt- acrylic prosthesis.https://edj.journals.ekb.eg/article_72720_bd0b5d560f89e568b2c96880f452fe8a.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101EFFECT OF AGING ON THE SHEAR BOND STRENGTH OF ZIRCONIA CERAMIC WITH DIFFERENT SURFACE TREATMENTS4534617272110.21608/edj.2019.72721ENShams Waaz AmgadAliLecturer of Fixed Prosthodontics, Faculty of Dentistry, Minia UniversityShereen KotbSalemLecturer of Fixed Prosthodontics, Faculty of Dentistry, October 6 UniversityJournal Article20200222Statement of the problem: Zirconia is an acid etching resistant ceramic and may cause difficulty in obtaining a safe bond with it. The aim of this study is to evaluate the effect of aging on the shear bond strength of zirconia ceramic after being subjected to different surface treatments. <br />Materials & Methods: Forty zirconia samples were constructed in the form of discs by copy milling. All the samples were 5mm in diameter and 1mm in thickness. The samples were divided into four groups according to the type of surface treatment they were subjected to, group1: control, group 2: subjected to etching using hydrofluoric acid 9% , group 3: sandblasting using 50µm Al2O3 particles and group 4 : silica coating using 50µm Al2O3 and 50 µm SiO2 particles. The samples were cemented on the occlusal surface of molar teeth using Rely XTM U200. Each group was further subdivided into two subgroups according to the type of test: shear bond strength before aging, shear bond strength after aging. The samples of the second subgroups were thermocycled (5– 55 °C/5,000 cycles) as aging procedure. Shear bond strength was measured. Data were tabulated and statistically analyzed using one-way analysis of variance (ANOVA).<br />Result: Results showed that the highest shear bond strength before aging was recorded by the silica coated samples while the lowest shear bond strength was recorded with the hydrofluoric acid etched samples. There was no statistical significant difference between all the tested different surface treated samples regarding shear bond strength before aging except the silica coated samples. After aging, the most affected samples with decrease in the shear bond strength were the control samples while there was no significant difference for the tested surface treatments.<br />Conclusion: Silica coating recorded the highest shear bond strength. Hydrofluoric acid etching and sandblasting are not reliable methods of surface treatment for production of safe and strong bond with zirconia. Aging has a significant effect on the control zirconia samples which showed decrease in the shear bond strength.https://edj.journals.ekb.eg/article_72721_4b32149359a2ef6e7137846ce5f09e7b.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Evaluation of Naturally Derived Hydroxyapatite Tissue Engineering Scaffold Coated With Chitosan-Carbon Nanotubes Composite4634747272210.21608/edj.2019.72722ENSalma M.FathyDental Biomaterials Dept., Faculty of Oral and Dental Medicine, Zagazig UniversityTarek A.ElkhoolyRefractories, Ceramics and Building Materials Department, National Research CentreAhmed A.EmamMedical Experimental Research Centre (MERC), Faculty of Medicine, Mansoura UniversityFikry M.ReichaExperimental Solid State Physics Dept., Faculty of Science, Mansoura University, EgyptJournal Article20200222Objective; This study aimed to valuate the effect of f-CNTs (functionalized carbon nanotubes) and chitosan (CS) composite on the mechanical properties and cell biocompatibility of carbonated HAp (hydroxyapatite) derived from cuttlefish bone. <br />Methods; The microstructure characterization of carbonated HAp after hydrothermal treatment showed complete transformation into highly crystalline structure. The prepared CS/f-CNTs composite was introduced into HAp specimens under vacuum. A compressive load was applied till failure using a universal testing machine to evaluate compressive strength and elastic modulus of aragonite (CaCO3) and treated HAp with CS/f-CNTs composite. The proliferating number and percentage of MSCs (mesenchymal stem cells) in direct contact with tested materials were used as indication of cytotoxic effect after 24, 36 and 72 hours in addtion alkaline phosphatase activity (ALP) after 12 days was used as indication of osteogenic effect. <br />Results; The HAp group with deposition of CS/f-CNTs composite showed a statistically significant higher compressive strength (0.82 ± 0.17 MPa) and elastic modulus (11.1 ± 1.06 MPa) and a statistically significant lower value for cell viability percentage (225,590 ± 8030.503, 32.95%) after 72 hours and ALP activity (85.51 ± 5.67 μU/μg protein) after 12 days of incubation. <br />Conclusions; Carbonated HAp scaffolds reinforced with CS/f-CNTs composite can be used in low stress bonny defects.https://edj.journals.ekb.eg/article_72722_8d11d4abc4a74cf2dba850516e7c6260.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of post-etching cleaning methods on surface micromorphology and shear bond strength of composite resin cement to feldspathic ceramic blocks4754827272310.21608/edj.2019.72723ENAhmedZiadaLecturer of Fixed Prosthodontics, Fixed Prosthodontic Department, Faculty of Dentistry, Benisuef University, Egypt0000-0002-8795-598XDobboCsabaProffesor of Radiology and Oral Diagnosis, Semmelweis University, HungaryJournal Article20200222Statement of the problem: Silica-based ceramics, such as feldspathic porcelain are widely introduced as laminate veneers and inlays/onlays due to their excellent esthetic properties. The success in achieving the right bonding protocol is the challenge which contributes to the restorations longevity.<br />Objectives: This study aimed to evaluate the effect of post etching surface cleaning protocol on the surface micromorphology and shear bond strength of resin cement composite to feldspathic ceramic blocks.<br />Materials and Methods: A total of sixty discs (fifty for the mechanical test and 5 for each scanning microscopic method) of feldspathic ceramic blocks (VITA MARKII) were prepared and etched with 9.5% hydrofluoric acid for 90 seconds the discs then randomly divided into five groups (N=10) HF not subjected to any cleaning step after HFl etching. The HHU group 37% phosphoric acid postetched for 30 seconds then immersed in ultrasonic bath for 5 minutes, the HHV group was postetched with 37% phosphoric acid for 30 seconds then vacuum dried, HV group was vacuum dried only. The HHUV group was postetched with 37% phosphoric acid for 30 seconds then immersed in ultrasonic bath for 5 minutes then vacuum dried. The surface of each disc was scanned for examination of the surface topography before and after surface treatments. Two different imaging techniques were used: scanning electron microscopy and laser confocal microscopy. Adhesive resin cement (NEXUS 3) was directly bonded to each ceramic disc using a special device providing the same thickness of the cement layer. All the samples were then subjected to shear bond strength tests. Statistical significances between groups were analyzed using one-way ANOVA and (SNK) multiple comparison tests.<br />Results: The results of the shear bond strength showed that there is significant difference between (HF) group and both HV or HHV groups, while showed no significant differences with any other groups where the ultrasonic bath was used. Laser confocal microcopy 3D data analysis showed significant difference in the surface roughness depth between the groups what is subjected to Ultrasonic bath (HHUV and HHU) and the other three groups. the analysis shows significant difference as well between (HF group) and (HV and HHV groups). While was no significant difference between (HV and HHV) groups.<br />Clinical implication Finding an exact protocol of post etching cleaning is of a big importance nowadays with the increased shifting towards the conservatism and esthetic dentistry and laminate veneers solutions which success depends mainly on the long term bonding strength.https://edj.journals.ekb.eg/article_72723_be89dbba2298568feb1b1ad4f1624cab.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Bite Force and Bone Height Changes around Abutments Retaining Mandibular Removable Partial Denture with Wrought Wire and Polyamide Clasps: Split Mouth Study4834917280410.21608/edj.2019.72804ENAhmed KhalifaKhalifaLecturer of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Egypt.NesreenElmekawyAssociate Professor of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, EgyptJournal Article20200222Objectives: This research highlights on the effect of polyamide clasp on the bone height changes of the abutment teeth and the bite force change comparing to conventional wrought wire clasp in a split mouth study. <br />Materials and Methods: This split mouth research was carried out on 14 partially edentulous participants with mean age (61.14) year. For every participant, a resin bilateral distal extension removable partial denture was constructed to be retained by a wrought wire clasp on one side and a polyamide clasp on the other. Standardized digital periapical radiograph was used to evaluate the abutment alveolar bone height change after 12 and, 18 months from denture insertion. Bite force transducer was used to measure the bite force for both clasp types sides at insertion and after 18 month of follow up.<br />Results: At comparing bone height change after insertion with the baseline, there was a significant increase in the bone resorption with the polyamide clasp after 18 month in mesial and distal aspect (p= 0.01 and 0.04 respectively); and after 12 month at mesial side (p=0.01). There is also a significant difference in bone height change around abutments carry both clasp types at 12 and 18 months in distal side (p= 0.03 and 0.001 respectively); and in the mesial side (p= 0.02 and 0.01 respectively). The evaluation of the bite force revealed significant difference between measurements at time of insertion and 18 months of for polyamide and wrought clasp sides (p= 0.02 and 0.043 respectively).<br />Conclusion: This study results illustrated that both types of clasps were appropriate to be used with the acrylic removable partial denture as their influence on the abutment alveolar bone resorption is within the acceptable range of bone resorption. While there is a nonrelated-clasp type improvement in bite force.https://edj.journals.ekb.eg/article_72804_604162157f0c83f287d938bd6f2a990f.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of different methods of vital tooth bleaching on the resistance of enamel to erosion using Energy–Dispersive X-Ray Spectrometry analysis4935117280610.21608/edj.2019.72806ENReham MohammedAttiaLecturer of Operative Dentistry, Department of Conservative Dentistry, Faculty of Dentistry, Zagazig University, Zagazig, Egypt.Eman Mohamed SobhyElbahrawyLecturer of Dental Biomaterials, Faculty of Dentistry, Tanta University, Egypt.Mona Elsaied Abd El HamedEssaAssociate Professor of Operative Dentistry, Faculty of Dentistry, Beni-Suef University, EgyptJournal Article20200222Objectives: the objective of the current study was to determine the effect of different methods of vital tooth bleaching (power in- office, at-home and over the counter) on the resistance of enamel to erosion. Material and methods: Square enamel sections (4 mm × 4 mm × 3 mm) were obtained from the middle third of the crown of bovine teeth and then embedded in self-curing acrylic resin blocks measuring (2 cm wide and 3 cm high). The samples were divided randomly into 4 groups according to the method of bleaching used. Group 1(control group): where all specimens of the group were placed in artificial saliva at 370 C during the study period. Group 2 (power in- office bleaching): The gel was applied directly on the enamel surface of the specimens where the thickness of the gel was about 1-2 mm, then the LED bleaching device was used. The lamp was located close to enamel surface, then it was turned on for 15 minutes for total application time 45 minutes. Group 3 (Crest 3D White Luxe Supreme FlexFit White strips (over the counter) : the strips were applied to the enamel surface for 30 min twice daily for 14 days according to manufacturer instructions. Group 4 (At-home bleaching): bleaching gel was applied to the enamel surface. Teeth were placed for 6 hours at 370C daily for 8 days. Then, all the samples were subjected to erosive challenge where the bleached samples and the samples of control group were immersed in 1% citric acid solution. Mineral analysis via EDS was carried out before bleaching (base line), then of bleached enamel and finally after erosive cycle. Two representative samples of each group after each step were examined by scanning electron microscope. Results: There was a significant difference regarding the percentage weight of (Ca%), (P%) and (Ca/P%) among the four tested groups. The difference was not significant between group 1 and group 4 after erosion. Conclusions: 1-At-home beaching is considered the least harmful to enamel compared to power in- office and over the counter bleaching materials, and it is more resistant to erosive challenges. 2- Bleaching agents containing calcium decrease the adverse effects of the bleaching procedure. 3-Bleached enamel is less resistant to erosion especially when power in -office or over the counter protocol is used.https://edj.journals.ekb.eg/article_72806_6426bd5a39e2cd77a541f11fd875afef.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101The Surface Gloss and Micro-hardness of Two Recent Tooth Colored Restorative Materials After In-office Bleaching5135217280710.21608/edj.2019.72807ENHebatallah M.TaherAssistant Professor of conservative Dentistry, Faculty of Dentistry Cairo University and Modern Sciences and Art in EgyptEman A.AbouaufLecturer of Conservative Dentistry, Faculty of Dentistry, Cairo University, EgyptJournal Article20200222The aim of this study was to compare the surface gloss and micro hardness of two types of tooth colored restorative materials (Ketac Universal Aplicap glass ionomer and Vertise Flow self adhesive resin composite), after the exposure to in-office bleaching agent. <br />Materials and methods: A total of twenty discs were divided into two equal groups of two tested restorative materials; Ketac Universal Aplicap Glass ionomer and Vertise flow self adhesive flowable resin composite. In-office teeth whitening gel was applied on each specimen surface. Measurement of the surface gloss and micro-hardness was done to all the specimens before and after the bleaching procedure. <br />Results: The surface gloss of both tested materials showed lower mean value after bleaching than before bleaching and was statistically significant. On the other hand, the micro-hardness of both tested materials showed lower mean value after bleaching than before bleaching and was statistically significant. <br />Conclusion: the surface configuration and micro-hardness of both tested materials were negatively influenced when subjected to in-office bleaching.https://edj.journals.ekb.eg/article_72807_c542d55b128cb8ee2cef2020be41ff09.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of different beverages on microhardness of Zirconia reinforced Glass Ionomer and micro-hybrid Resin composite5235307280810.21608/edj.2019.72808ENHebaBahgatAssistant Professor of Operative Dentistry, Faculty of Dentistry, King Abdul Aziz University, Saudi Arabia. Lecturer
of Operative Dentistry,Faculty of Oral and Dental medicine, Suez Canal University, EgyptHadeelFaroukLecturer of Operative Dentistry,Faculty of Oral and Dental medicine, Ahram Canadian University, Egypt.Journal Article20200222Objective: This study aimed to evaluate the influence of commonly used beverages, on surface microhardness of Zirconia reinforced glass ionomer (Zirconomer improved) and microhybrid resin-based composite (Filtek Z250).<br />Materials and methods: A total of 40 disk-shaped specimens were fabricated (20 discs from each type of material). Ten Specimens from each material were immersed in Instant Coffee and the other ten Specimens were immersed in Cola. After initial microhardness recording, each group was subject to thermocycling and then microhardness was re-assessed (n= 10). <br />Results: It was observed that each of restorative material type, thermocycling, and immersion solution, had a statistically significant effect on mean microhardness of both tested materials irrespective of the other tested variables.<br />Conclusion:Resin composite showed significant higher hardness values when compared to Zirconia reinforced glass ionomer. There was a significant decrease in hardness in both materials after thermocycling, with a significant influence of soft drinks more than instant coffee.https://edj.journals.ekb.eg/article_72808_3d89c3b44401790ad54b98d4a270aae7.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Five-year Radiographic Changes of Residual Ridges under Maxillary Complete Denture and its Opposing Mandibular Two Implant-Retained Overdenture with Different Resilient Attachments5315407280910.21608/edj.2019.72809ENRadwa M. K.EmeraAssociate Professor, Removable Prosthodontics Department, Faculty of Dentistry, Mansoura University. Mansoura. EgyptElsayed A.Abdel-KhalekLecturer, Removable Prosthodontics Department, Faculty of Dentistry, Mansoura University. Mansoura. EgyptJournal Article20200222Aim: This study aimed to radiographically compare the effect of different resilient attachments on maxillary and mandibular residual ridge changes after 5 years of using mandibular 2-implant retained overdentures. <br />Materials and methods: Eighteen completely edentulous male patients, with age ranging from 45 to 60 years, were included in the study. Maxillary complete dentures were constructed opposed to 2-implant retained mandibular overdentures. Patients were divided randomly into three equal groups according to type of attachment into; ball/socket (BOD) group, Locator attachment (LOD) group, and positioner attachment (POD) group. Maxillary and mandibular ridge resorption were determined by using the proportional area index method on the panoramic radiograph taken at time of overdenture insertion and at five years later.<br />Results: The minimal rate of ridge resorption was recorded for posterior maxillary ridges (Max-PRRR) followed by that of posterior mandibular ones (Mand-PRRR), while the highest resorption rate was recorded for anterior maxillary ridges (Max-ARRR). The study did not reveal significant difference in ridge resorpion between the resilient attachment systems.<br />Conclusion: Mandibular overdentures retained by two implants with the described attachment systems provide a similar and acceptable range of residual ridge resorption (RRR) after 5years of function. The reduced RRR with Locator attachments proved its ability to provide an equitable load on the implants and tissue bearing areas during function.https://edj.journals.ekb.eg/article_72809_805c5ca89aa5bafe7060040a72224781.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Matrix Metalloproteinase Inhibitor from Mulberry fruit extract on the Microtensile Bond Strength Stability: An in vitro Study5415507281110.21608/edj.2019.72811ENRaniaMosallamConservative Dentistry Department, Faculty of Dentistry, Cairo University, EgyptNerminYounisPharmacognosy Department, Faculty of Pharmacy, Ahram Canadian University, EgyptHadeelFaroukOperative Dentistry Department, Faculty of Oral and Dental Medicine, Ahram Canadian University, EgyptOsamaMosallamRestorative and Dental Material Research Department, National Research Centre, EgyptJournal Article20200222Objectives: The present in vitro study aimed to analyze the effect of two Mulberry fruit extracts on microtensile bond strength of an etch & rinse adhesive immediately and after thermocycling.<br />Materials and Methods: Flat dentin surfaces of 30 sound human molars were bonded with an etch and rinse adhesive. Dentin surfaces were left untreated (control group) or were pretreated with either Morus alba water extract, Morus alba alcohol extract, Morus nigra water extract or Morus nigra alcohol extract. Nano-hybrid resin composite were incrementally built-up. The tooth/composite specimen was serially sectioned in order to produce beams of 0.9±0.1 mm in thickness. Each group was subdivided into two subgroups whether the teeth/composite specimens subjected to thermocycling or not. Each beam was individually fractured by a micro tensile testing machine. The data recorded in MPa, were tabulated and statistically analyzed.<br />Results : Specimens treated with Morus alba and Morus nigra water extracts yielded significantly higher mean bond strengths than alcohol extracts in immediate micro-tensile bond values and after thermocycling. In addition ,Morus alba water extract revealed no statistically significant difference immediately and after thermocycling. <br />Conclusion : Dentin pretreatment with Mulbery water extracts has no adverse effect on the immediate microtensile bond strength and it was able to maintain bond stability of adhesive to dentin.https://edj.journals.ekb.eg/article_72811_9ff98c0cad28a91afc115cac12d15b68.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Repair potentiality of CAD/CAM composite block and hybrid ceramic block by direct resin composite restoration with and without surface treatment5515627281210.21608/edj.2019.72812ENAhmedEl ZohairyAss. Professor of Conservative Dentistry, Faculty of Dentistry, Cairo UniversityAmirHafezLecturer of Conservative Dentistry, Faculty of Dentistry, Cairo UniversityHaithamAmrLecturer of Fixed Prosthodontic, Faculty of Dentistry, Fayoum UniversityJournal Article20200222Objective: to evaluate microshear bond strength of CAD/CAM composite block and hybrid ceramic block repaired by direct resin composite restoration with and without surface treatment.<br />Materials and Methods: Two different CAD/CAM restorative materials were tested in the present study: hybrid ceramic blocks (Vita Enamic) and resin composite blocks (Grandio). Six sections were prepared from each CAD/CAM blocks. The sections from each block type were randomly divided into three groups according to the surface treatment performed. Control group: the specimens were ground with a grinding machine. Etching gel Group: 37% phosphoric acid etching gel was applied occlusally on the surface of the section and CoJet Group. the surface of all groups were then silanized using Bis-Silane then bonding agent Futura bond DC was applied. A polyethylene micro tubes were prepared that were held in place with a tweezer on the uncured then light cured for 10 seconds Resin composite (Grandioso X-tra) was packed inside the microtubes and light cured. All specimens were prepared by the same operator at 22.0–22.5 ˚C (room temperature) and relative humidity of 50%. The specimens were further divided into two groups according to storage conditions. Half of the specimens were thermocycled in distilled water for 5000 cycles in a 5–55˚C water bath with a dwell time of 30 seconds and a transfer time of 5 seconds. The other specimens were stored in distilled water for 2 days. Microshear bond strength was performed and fractographic analysis to determine the failure mode. Statistical analysis was then performed using a commercially available software program (SPSS 19; SPSS, Chicago, IL, USA). As data were not normally distributed, significance of the difference between different groups within the same surface pretreatment was evaluated using Kruskall Wallis test. Mann Whitney U test was used for pairwise comparisons and to study the effect of surface pre-treatment. The interaction of restoration and type of pretreatment variables was evaluated using 3 ways ANOVA. The level of significance was set at P < 0.05.<br />Results: Three ways ANOVA test revealed that each of the material type (composite/hybrid ceramic), the subgroup type group (control/etching/Cojet) and the thermocycling (Yes/No) variables resulted in a statistically significant difference (p=0.00, p=0.00, p=0.003 respectively). Interaction of the subgroup (control/etching/Cojet) variable with the thermocycling (Yes/No) variable and the material (composite/hybrid ceramic) variable showed a statistically significant difference (P=0.023, p=0.001 respectively). Moreover, interaction of thermocycling and material variable resulted in a significant difference (p=0.034). However, interaction of the 3 study variables (material, subgroup, thermocycling) was not statistically significant (p=0.165). The failure mode of the tested specimens analyzed using Scanning Electron Microscope at magnification 80X was commonly mixed type of failure (adhesive failure between resin composite restoration and CAD/CAM blocks with cohesive failure within resin composite restoration).<br />Conclusions: Grandio composite blocks is very promising materials and their optimum long lasting repair potentiality that offers to the clinicians great chance to easily repair the defective restoration with safety. Surface treatment using Phosphoric acid or Cojet system greatly improve the bond strength between composite repair system and hybrid ceramic or composite blocks. The bond performance of repaired composite blocks was much more greater than than that of repaired hybrid ceramic. Thermocycling affect the bond durability of repaired hybrid ceramic blocks and composite blocks.Further investigations focusing on the effect of different surface treatments to yield results that lead to concrete clinical recommendations are needed to evaluate the long term durability of new CAD/CAM materials.https://edj.journals.ekb.eg/article_72812_06f44d4677198c018f8530c38f0271c5.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101MICROBIOLOGICAL AND IMMUNOLOGICAL EFFECTS OF MONOMER FREE THERMOSENS AND NANO ZIRCONIA OXIDE REINFORCED DENTURE BASE RESINS ON CONTROLLED DIABETIC DENTURE WEARERS5635777281410.21608/edj.2019.72814ENAmira M.GomaaAssistant Professor, Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
Associate Professor, Removable Prosthodontics, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi ArabiaHanadi A.LamfonAssociate Professor, Removable Prosthodontics, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi ArabiaYahia A.MaherAssistant professor, Microbiology, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi ArabiaJournal Article20200222Background: The overall success of denture base resins depends on both mechanical behaviour and biocompatibility, especially in the rehabilitation of diabetic patients. The growth and nourishment of microorganisms is enhanced in diabetes mellitus specially in presence of dentures resulting in denture stomatitis. This study was prompted to assess the microbiological growth and the development of salivary immunoglobulin A (s-IgA) in relation to newly introduced denture base materials used in the rehabilitation of diabetic patients.<br />Materials and Methods: Forty eight completely edentulous patients were selected and divided into two groups: group (A), which included controlled diabetic patients and group (B) included non-diabetic patients. Each group was further divided into four sub groups according to the denture base material. Sub group I, patients were received thermoplastic VertexTM ThermoSens denture bases; sub group II, patients were received heat cure acrylic resin dentures reinforced with nano zirconia oxide particles (nano-ZrO2); sub group III, patients were received conventional heat cure acrylic resin dentures; where sub group VI, patients were received conventional heat cure acrylic resin dentures relined with self-cure acrylic resin. For each participant, non-stimulated saliva samples were collected before denture insertion, and one, two and three months after wearing dentures. Samples were inoculated and incubated both aerobically and anaerobically on selective media for Streptococcus mutans, Lactobacilli and Candida. Then, isolated microorganisms were identified, the characteristic colony forming units per millilitre (CFUs/ml), were calculated and the salivary immunoglobulin A level was measured by Enzyme-linked immunosorbent assay (ELISA).<br />Results: The results revealed increase in the CFU values of Candida, Streptococcus mutans, Lactobacilli and the level of salivary immunoglobulin A in all the assessed patients following denture insertion. However, significant lower values were evident in patients rehabilitated with ThermoSens and nano-ZrO2 reinforced bases compared to heat cure acrylic and self-cure relined bases. Significant increase in CFU values and level of s-IgA were found in diabetic compared to non-diabetic patients after insertion of all denture bases. Conclusion: ThermoSens and nano-ZrO2 reinforced denture bases showed less microbial growth and salivary immunoglobulin A level compared to heat cure and self-cure relined bases in both controlled diabetic and non-diabetic patients, hence, more biocompatible. <br />Keywords: Thermoplastic polyamide, Vertex ThermoSens, Reinforced acrylic, Zirconia oxide nanoparticles, Diabetes mellitus, Candida, Oral bacteria, Salivary Immunoglobulin A.https://edj.journals.ekb.eg/article_72814_6eedf29ce49f0b91bc69868faf33cb7d.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101The effect of number of telescopic PEEK crowns on unilateral free-end saddle supporting structures. A strain gauge stress analysis study5795867281510.21608/edj.2019.72815ENSahar A.GhorabLecturer, Faculty of Oral and Dental Medicine, Cairo UniversityDoaa A.RostomLecturer, Faculty of Oral and Dental Medicine, Cairo UniversityJournal Article20200222The aim of this in vitro study was to evaluate the strain induced on the last natural abutment and the unilateral free end saddle supporting area in case of using two splinted telescopes VS using single telescope with removable partial dentures. Costruction of two epoxy resin casts was done these casts were of Kennedy class II lower with the last standing tooth is the first premolar, simulation of periodontal ligaments and alveolar mucosa was done with rubber, For the first cast PEEK telescopic crowns were constructed on first premolar only while for the second cast it was done on both canine and first premolar. Then chrome cobalt removable partial dentures were done where the secondary coping are attached to its fitting surface. Using two strain gauges fixed on each cast one on the free end saddle area and the other was distal to the first premolar. Using loading machine and strain meter, load was applied on two sites the second premolar and the first molar .collected data were statistically analyzed .It showed significant difference between the two casts, where micro strains were higher in case of using only one telescope where it was less with two telescope .also micro strains were less on the residual ridge than on the distal side of the first premolar in both casts. In conclusion, different designs of RPDs will have different effects on abutments and residual ridges but many studies suggested using telescopic crowns as an appropriate treatment options for such cases as it ensures maximally favorable masticatory force transmission, which always takes place axial to the abutments. This treatment modality can lead to predictable long-term treatment outcomes. The limitations in this study were that it was carried out in vitro without considering the variation in clinical situations of different patients. Thus future clinical trials should be carried out to confirm any concluded results. https://edj.journals.ekb.eg/article_72815_21fb27251878ee81058b51cb32643258.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101THE EFFECT OF TWO DIFFERENT ANTIOXIDANTS ON THE SHEAR BOND STRENGTH OF RESIN BONDED GLASS CERAMICS TO BLEACHED ENAMEL5875987281610.21608/edj.2019.72816ENMohamed Mohey EldinMohamedLecturer of Fixed Prosthodontics, Delta University For Science and TechnologyJournal Article20200222Aim of the work: The aim of this study was to evaluate the effect of antioxidant agents and delayed bonding on the shear bond strength (SBS) of glass ceramic veneers bonded to the bleached enamel.<br />Materials & Methods: A total number of sixty extracted maxillary central incisors with intact labial enamel were collected and randomly divided to six groups of ten teeth each. Ten teeth were remain without bleaching and the remaining fifty teeth were bleached using 35% hydrogen peroxide, (SDI Polaoffice tooth whitening system ). Sixty lithium disilicate glass ceramic discs of 4mm diameter and 5mm height were fabricated from IPS e.max Press and divided to six groups of ten discs each. Group I glass ceramic discs bonded to the unbleached enamel surface. Group II glass ceramic discs immediately bonded the bleached enamel after bleaching procedure without antioxidant. Group III glass ceramic discs immediately bonded to the bleached enamel after 10% ascorbic acid antioxidant application to the bleached enamel. Group IV glass ceramic discs immediately bonded to the bleached enamel after 20% ascorbic acid antioxidant application to the bleached enamel. Group V glass ceramic discs immediately bonded to the bleached enamel after 2% green tea antioxidant application to the bleached enamel. Group VI glass ceramic discs bonded to the bleached enamel after 2 weeks waiting period. The tested specimens, were tested for shear bond strength using a universal testing machine at a crosshead speed of 0.5mm/min until failure. The failure load was then recorded and statistically analyzed.<br />Results: Analysis of the mean SBS between all groups it was found that the highest mean SBS for the control group CG of 30.22 ±0.92 MPa followed by group VI, with a mean of 26.90 ±1.27 MPa and group V with a mean of 26.0 ±1.80 MPa then group III, with a mean of 25.0 ±1.60 MPa and group IV with a mean of18.99±1.69 MPa the lowest mean fracture loads of 13.25± 0.36 MPa was for group II. <br />Conclusions : Within the limitations of this study, it was concluded that antioxidant agents neutralize the effect of bleaching agents and considered a viable alternative to delayed waiting period.https://edj.journals.ekb.eg/article_72816_6484a71f048dcacad0f05f60762c0b1b.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Fracture resistance of different esthetic partial coverage restorations5996097281710.21608/edj.2019.72817ENShaimaa AhmedAbo El-FaragLecturer at Department of Fixed Prosthodontics, Faculty of Dentistry, Mansoura University, EgyptMohammed SamirEl NawawyLecturer at Department of Operative Dentistry, Faculty of Dentistry, Mansoura University, EgyptJournal Article20200222Statement of problem: The main factors for long-term success of indirect esthetic restorations are referred to type of restoration and preparation design.<br />Purpose: The aim of this in vitro study was to evaluate the fracture resistance and modes of failure of composite, ceramic and hybrid partial coverage restorations with different preparation designs.<br />Material and methods: A total of 42 caries-free maxillary human premolars extracted for orthodontic reasons were collected from oral surgery department, Faculty of Dentistry, Mansoura University. Teeth were divided into 3 groups (n=14) according to type of restoration materials. Each group were subdivided into 2 subgroups (n=7) according to preparation design; palatal coverage onlay design in which the palatal cusp was reduced by 2 mm and complete onlay design in which preparation included the reduction of palatal and buccal cusps. Restorations were manufactured from indirectly fabricated composite (SR Nexco), Zirconia-reinforced glass ceramic (VITA SUPRINITY) and Hybrid ceramic (VITA ENAMIC). The finished onlays were luted to prepared teeth using self-adhesive resin cement (Rely X Unicem). Specimens exposed to thermocycling 5000 cycles and then cyclic loading for 500,000 cycles. The fracture resistance of specimens were evaluated in a universal testing machine. The results were analyzed by 2-way ANOVA and Tukey HSD post hoc tests. <br />Results: The results of two way ANOVA test showed that there was statistically significant difference between all groups regardless of the restorative materials and preparation design. Post Hoc test showed a statistically significant difference between three restorative materials in palatal and complete coverage onlay groups (P<0.05). There was no statistically significant difference in the interaction between the types of restoration and preparation deign (P=0.479) (p>0.05).<br />Conclusions: Zirconia-reinforced glass ceramic still the material of choice for palatal and complete onlays because of their strengthening effect on the tooth. Complete onlays showed maximum reinforcement of the tooth structure.https://edj.journals.ekb.eg/article_72817_829e9476a077aee7ab4e9808414c1639.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Oral health related quality of life in hemimaxillectomy patients rehabilitated with obturator prosthesis fabricated using different materials6116187281910.21608/edj.2019.72819ENMostafa IFayadAssistant Professor of Removable Prosthodontics, Faculty of Dental Medicine, Al- Azhar University, Cairo, EgyptIhab MAtitoLecturer of Removable Prosthodontics, Faculty of Dental Medicine, Al- Azhar University, Cairo, EgyptMahmoudAmmarAssistant Professor of Removable Prosthodontics, Faculty of Dental Medicine, Al- Azhar University, Assut, EgyptJournal Article20200222Objective: This study was conducted to evaluate oral health-related quality of life with different obturator materials in hemimaxillectomy patients. <br />Patients and Methods: Fourteen hemimaxillectomy patients were received a conventional obturator with combined metallic and heat cured acrylic resin. (Vertex™ Regular, Vertex-Dental B.V. Netherlands (Group I). Then the Patients received obturator constructed from a thermoplastic denture base . (Vertex™ Thermo Sens, Vertex-Dental B.V. Netherlands) (Group II). Oral health-related quality of life was measured after six months of obturator use using Functional Obturator Scale scores. Statistics were done using paired t-test to compare the oral health impact profile scale for edentulous patients in both groups. <br />Results: The mean total Functional Obturator Scale score [FOS] for group I and group II were 34.55 and 30.48 respectively. There was a a statistical significant different between both groups in relation to the mean total Functional Obturator Scale Score (P<.05). <br />Conclusions: It was concluded that after six months of obturator use in hemimaxillectomy patients, using a thermoplastic obturator resulted in a better oral health related quality of life than a conventional one. Therefore, it should be considered a treatment plan option to improve oral health-related quality of life.https://edj.journals.ekb.eg/article_72819_e7116f1a3a069207fddcd848907a6f6c.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101EVALUATION OF MECHANICAL PROPERTIES OF EXPIRED AND NON-EXPIRED RESIN COMPOSITE. A COMPARATIVE STUDY6196287282010.21608/edj.2019.72820ENAhmedAdel A. AzizLecturer of Conservative Dentistry, Faculty of Dentistry, Badr University in Cairo (BUC), Cairo, EgyptJournal Article20200222This in-vitro study evaluated the mechanical properties in terms of microhardness and degree of conversion of expired versus non-expired resin composite. A total of 120 standardized specimens were prepared for this study using Ceram.x one (E2 Enamel shade) resin composite, of which forty specimens were prepared using valid resin composite (E-0), the other forty specimens were prepared using 6 months-expired resin composite (E-6) and the last forty specimens using 12 months-expired resin composite (E-12). They were light cured using LED curing unit. 20 of each group were subjected to measurement of surface microhardness in Vickers hardness tester. The depth of cure was calculated by obtaining the microhardness ratio through dividing VHN of the bottom surface by VHN of the top surface. The other 20 specimens of each group were tested for the degree of conversion using Fourier transform infrared spectroscopy (FTIR). Data was then recorded, tabulated and statistically analyzed. The highest mean microhardness of the specimen’s top was recorded for the group of 12-months expired resin composite (E-12: 83.17 ± 3.14), which was significantly different in relation to the group of 6-months expired resin composite (E-6: 72.17 ± 2.55) and the group of valid resin composite (E-0: 72.06 ± 4.20). Regarding B/T ratio (%), there were no statistical significant difference between the three groups (E-0: 69.3 ± 10.1; E-6: 66.8 ± 3.9; E-12: 67.9 ± 4.9). As for the degree of conversion results there was no statistical significant difference between the three groups (E-0: 1.48 ± 0.14; E-6: 1.68 ± 0.20; E-12: 1.74 ± 0.18). In conclusion, expired resin composite within1 year interval showed optimum and accepted mechanical properties in terms of Degree of conversion and microhardness compared to that of non-expired resin composite.https://edj.journals.ekb.eg/article_72820_6f7fd71121f51261d9ce2431e1ea4c4d.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Vented and Closed Abutments on Peri-Implant Soft and Hard Tissues - Clinical and Radiographic Assessment6296397282110.21608/edj.2019.72821ENMaged MohammedZohdyAssociate Professor of Fixed Prosthodontics, Ain Shams University and British UniversityWaleed MohamedAbbasLecturer of Oral Medicine, Periodontology and Oral Diagnosis, Ain Shams University and Future UniversityJournal Article20200222Excess cement found on tooth-retained restorations with healthy periodontal tissues present few if any problems. The cement-retained implant restoration may be more vulnerable to the effects of cement entering the soft tissues and residual excess cement on the implant restoration when compared to a tooth. It has been hypothesized that an open/hollow abutment may provide an internal reservoir for cement.<br />Materials and methods: The patients included in the study were divided into two groups according to the abutment design that was used after implant placement; closed abutment group (CA) where 7 crowns were cemented on closed abutments vented abutment group (VA) where 7 crowns were cemented on vented abutments. |Re-examination was scheduled 3, 6 and 12 months after crown cementation. Periodontal assessment included Bleeding Index (BI) and Probing depth (PD). Bone height measurements were performed using cone beam computed tomography to measure the marginal bone loss.<br />Results: Considering different intervals of the follow-up period, the differences in BI and PD between tested groups (vented and closed abutments) were statistically non-significant (p>0.05), but there was a statistically significant increase in PD for comparison between PD at different time periods in each group after 6 months as well as from 6 months to 12 months. <br />After 3, 6 as well as 12 months, Group CA showed statistically significantly higher mean amounts of bone loss than Group VA.<br />Conclusions: (1) Vented abutments exhibit better soft tissue response and less marginal bone loss when compared to closed abutments through one year follow up. (2) Soft tissue response and marginal bone loss associated with both abutment designs were within the normal health limits after one year follow up period of the study.https://edj.journals.ekb.eg/article_72821_b0d57366c448449539395299e80b0a4b.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Different Surface Treatment Modalities on Surface Roughness and Shear Bond Strength of Orthodontic Molar Tubes to Lithium Disilicate Ceramics6416567282210.21608/edj.2019.72822ENRania EBayoumiLecturer, Biomaterials Department, Faculty of Dentistry (girls), Al-Azhar UniversitySara M.El-KabbanyLecturer, Orthodontic Department, Faculty of Dentistry (girls), Al-Azhar UniversityNevinGadLecturer, Operative Dentistry Department Faculty of Dentistry (girls), Al -Azhar UniversityJournal Article20200222Objectives; This study aimed to evaluate the effect of different surface treatment modalities on surface roughness(SR) and shear bond strength (SBS) of orthodontic molar tubes to lithium disilicate (IPS e-max CAD/CAM, Ivoclar Vivadent) ceramic and human enamel using different adhesives.<br />Materials and methods: A total of 150 e-max specimens were randomly divided into five groups (n=30) according to the method of surface treatment used. In group I (control group): no surface treatment, group II: sandblasting with 50 μm Al2O3 slurry particles, group III: etching with hydrofluoric acid 9.6%, group IV: etching with hydrofluoric acid 4.5% and group V: etching with phosphoric acid 37%. Further random distribution of e-max specimens into subgroups was performed according to the type of adhesive used (One coat 7, G-Premio Bond and Ortho solo). The surface roughness was investigated using digital profilometer and atomic force microscopy (AFM). Microstructural analysis was conducted using scanning electron microscope (SEM).The SBS was measured using universal testing machine. Results were statistically analyzed.<br />Results: Results showed that the sandblasting group had significantly highest surface roughness, while the lowest value was recorded in the Phosphoric acid 37% group. Furthermore, sandblasted group showed the highest SBS, while control group showed the lowest SBS. Strong positive correlation was found between the surface roughness of lithium disilicate and shear bond strength. Meanwhile, no significant differences were found between different adhesive agents use.<br />Conclusions: Shear bond strength was highly affected by the surface roughness which subsequently controlled by the surface treatment modalities and not by the adhesives types. Hydrofluoric acid 4.5% and phosphoric acid 37% are recommended techniques for reliable bond strength between metal tubes and lithium disilicate ceramic.https://edj.journals.ekb.eg/article_72822_09ff21acd53f6ef4f6ef7175f3e4a4c8.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of different finishing and polishing systems on surface roughness and color changes of resin composites: An in vitro study6576667282310.21608/edj.2019.72823ENOlaBarakatAssosciated Professor, Conservative Department, Dentistry program,IbnSina National College for Medical
Studies, Jeddah, Saudi ArabiaMuhammadAbbasAssistant Professor, Dental Biomaterials, Faculty of Dental Medicine, Al Azhar University Cairo, EgyptJournal Article20200222Background and objective: Finishing and polishing techniques have great importance on the long-term success and aesthetics of the composite restorations. This study aimed to investigate the effect of three finishing and polishing systems on surface roughness and color changes of four different posterior composites. <br />Materials and Methods: Four different posterior composites, nanohybrid, nano-fill, sonic-activated bulk-fill and microhybrid resin-based composite, and three different finishing and polishing systems, Sof-Lex discs, Astropol® and TOR VM discs were used in the study. The disc specimens (15 disc for each resin composite with total n=60) were 10 mm in diameter and 2 mm in height. Before and after finishing and polishing procedure, surface roughness was measured with a profilometer device and the Ra values were recorded. Color changes was examined using spectrophotometer and (ΔE) values were calculated. Data were tabulated and statistically analyzed using analysis of variance and Tukey’s test at significance level of p<0.05. <br />Results: There was no significant difference among the composite resins or the finishing and polishing systems used on surface roughness (p > 0.05) although all composites showed a smoother surface after finishing and polishing procedures. As regard to color changes (ΔE) statistically significant difference was found between composite groups and finishing and polishing system used (p < 0.05). A direct correlation between Ra and ΔE values was found. <br />Conclusions: 1.surface roughness and color stability of resin composite restorations depend mainly on the material compositions and polishing procedure. 2. The effectiveness of the polishing systems was material dependent. 3. Among the material tested, Nanohybrid presented the smoothest surfaces and the least color changed material. 4. The polishing systems in this study, the best system was the TOR VM discs polishing system with respect to the surface roughness and color changes values. 5. Developments in finishing and polishing systems are important for the creation of ideal restorations and are associated with the increased clinical success of dental practitionershttps://edj.journals.ekb.eg/article_72823_6e2c7c031bc83a8fc08f67a9da3de1cc.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Assessment of resin -ceramic bond strength under various pH conditions for different ceramic materials subjected to two surface treatment protocols6676797282810.21608/edj.2019.72828ENRehamElbastyLecturer Fixed Prosthodontic Department, Faculty of Dentistry. Cairo UniversityMahaTaymourAssociate Professor Fixed Prosthodontic Department, Faculty of Dentistry. Cairo University.Journal Article20200222Statement of the problem: The 2 step ceramic surface treatment “ HF acid etching followed by silane application” has been used for years to secure an efficient bond between ceramics and resin cements, however the urge for simplification and making the bonding procedure less technique sensitive have pushed the dentists to shift to one step ceramic surface treatment “self etch ceramic primer”. Although studies proved their reliability, till now there is no data available on their effect on bond stability in different pH conditions <br />Purpose: The aim of the current study was to evaluate microshear bond strength between resin and different ceramic materials (e.max, VITA ENAMIC and VITA SUPPRINITY) preatreated with two different protocols (2 step and 1 step) after being subjected to various pH storage media<br />Materials and Methods: A total of ninety ceramic discs were fabricated in this study from CAD/CAM blocks. The discs were divided into three groups according to ceramic material as follows; Group 1: Thirty discs constructed from lithium disilicate glass ceramic (e.max CAD), Group 2: Thirty discs constructed from polymer infiltrated ceramic- network material (VITA ENAMIC) and Group 3: Thirty discs constructed from Zirconia-lithium silicate glass-ceramic materials (VITA SUPRINITY). Each of the previous groups were further subdivided into two equal subgroups according to the surface treatment protocol used as follows; Subgroup 1: fifteen discs were treated with 2 step bonding protocol (etched with hydrofluoric acid followed by silane application) and Subgroup 2: fifteen discs were treated with 1 step application of self etching primer (Monobond etch and prime). The two subgroups were again equally divided (5 each) and assigned to one of the three storage solutions with different pHs : acidic, neutral and alkaline media.Ceramic discs were obtained by sectioning the CAD/CAM blocks using Isomat 1000 followed by crystallization of the e.max and VITA SUPPRINITY discs. For first subgroup, the ceramic discs were subjected to two step surface treatment protocol consisting of hydroflouric acid etching, rinsing followed by silane application. While the second subgroup was subjected to surface treament using one <br />step monobond etch and prime protocol. For both subgroups,each ceramic substrate was then prepared to receive 5 resin microtubules. Five samples of each ceramic resin assembly subgroup was then randomly selected and designated in one of the following storage media for a period of seven days:1) Cola solution representing acidic medium having pH value of 2.5. 2) Distilled water representing neutral medium having pH value of 7 3) Licorice solution representing alkaline medium having pH value of 8.4. At the end of the storage period,micro shear bond strength test was performed to debond the specimens in a universal testing machine (Model 3345; Instron Industrial Products, Norwood, MA, USA) 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: With acidic pH: in e.max CAD and VITA ENAMIC groups; it was found that two steps surface treatment approach recorded statistically significant higher mean microshear bond strength value than one step approach as proven by paired t-test (P<0.05), while for VITA SUPRINITY group; it was found that two steps surface treatment approach recorded statistically non-significant higher mean microshear bond strength value than one step approach as demonstrated by paired t-test (P= 0.1945> 0.05). With neutral pH: in e.max CAD and VITA ENAMIC groups; it was found that two steps surface treatment approach recorded statistically non significant higher mean microshear bond strength value than one step approach as proven by paired t-test (P>0.05), while for VITA SUPRINITY group; it was found that two steps surface treatment approach recorded statistically significant higher mean microshear bond strength value than one step approach as demonstrated by paired t-test (P= 0.03<0.05)With alkaline pH: : in e.max CAD and VITA ENAMIC groups; it was found that two steps surface treatment approach recorded statistically significant higher mean microshear bond strength value than one step approach as proven by paired t-test (P<0.05), while for VITA SUPRINITY group; it was found that two steps surface treatment approach recorded statistically non-significant higher mean microshear bond strength value than one step approach as demonstrated by paired t-test (P= 0.2121> 0.05)<br />Conclusions: Within the limitations of this study, the following conclusions and clinical recommendations could be advised:1) Although microshear bond strength of the two step etch and prime surface treatment protocol was significantly higher than that of one step self-etching ceramic primer protocol,however the values for all tested materials under various Ph conditions were nearly within a clinically acceptable range, thus it could be suggested that self etching primers can be safely used without affecting clinical performance of the restorations. 2) In patients subjected to predominately acidic or alkaline oral pH environments, both surface treatment protocols can be safely used when VITA SUPPRINITY restorations are indicated, however when VITA ENAMIC or e.max CAD are used, it is recommended to use the two step surface treatment protocol to ensure more stable bond strength 3) In patients having a neutral balanced oral pH environment, both surface treatment protocols can be safely used when VITA ENAMIC or e.max CAD restorations are used, however when VITA SUPPRINITY is recommended, it is advisable to use the two step surface treatment protocol to yield better ceramic resin bond durability. 4) Generally speaking, VITA ENAMIC restorations combined with one step self etching primer are not recommended for patients having acidic pH oral media as it yielded the lowest bond strength values between all subgroupshttps://edj.journals.ekb.eg/article_72828_1c37ff196a5511b3355e93b5db5ba8d2.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Evaluation of one-visit apexification with MTA apical plug versus traditional Calcium hydroxide apexification with the help of Platelet Rich Fibrin apical matrix6816907282910.21608/edj.2019.72829ENMohammedE RokayaLecturer of Endodontics, Faculty of Dental Medicine, Al-Azhar University (Assuit Branch) - EgyptElsaeedAbdel HafizLecturer of Endodontics, Faculty of oral and Dental Medicine, Future University, Cairo, Egypt.Journal Article20200222This study aimed to evaluate one-visit apexification with MTA apical plug versus traditional calcium hydroxide apexification with the help of platelet rich fibrin (PRF) apical matrix. Methods: 18 immature permanent maxillary anterior teeth with non-vital pulp were chosen from 14 children ranging from 9 to15 years old, and were divided randomly into two main groups with 9 teeth in each group [Group I MTA, and Group 2 Ca(OH)2]. Platelet Rich Fibrin was used for both groups as internal apical matrix. In group 1 MTA approximately 4-5 mm thickness of mixed MTA apical plug was placed at the apical end of the root, then the canal was obturated by Obtura II system after 24 hours, while in group 2 Ca(OH)2 ; the apexification was done by Ca(OH)2 and renewed at 3,6 months and after 12 months the canal was obturated by Obtura II system. The radiographs were taken for all cases at preoperatively, post operatively and at 3, 6 and 12 months follow up. Data were subjected to statistically analyze. Results: At 12 months follow up period 100% of teeth with calcific apical barrier were detected in Group 1 MTA, and 88% of teeth with calcific apical barrier were detected in Group 2 Ca (OH)2. However, there was no difference in statistically point of view between the groups. Conclusions: One-visit apexification provides an alternative treatment option over the traditional calcium hydroxide apexification in treating the non-vital cases with open apices.https://edj.journals.ekb.eg/article_72829_709ef93bcc8b5b706cd5a8dc765be976.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Influence of two different implant designs on implant stability6916997283110.21608/edj.2019.72831ENMahaNagiLecturer, Removable Prosthodontics Department, Faculty of Dentistry, British University in EgyptJournal Article20200222Aim of the study: To evaluate and compare the influence of the conventional solid-structure (CSS) implants versus the direct metal laser sintering (DMLS) implants regarding primary and secondary stability.<br />Materials and methods: A total of 12 implants of two different designs were tested , six partially edentulous male patients having full set of teeth upper arch opposed by Kennedy class I lower arch with second premolar as last standing abutment bilaterally received twelve implants at the second molar area bilaterally, each patient received two implants of the same size, diameter and implant abutment connection, one conventional solid-structure (CSS) implants (control group) at the right side and one direct metal laser sintering (DMLS) implant (test group) at the left side. Primary and secondary implant stability were measured and compared by resonance frequency analysis using osstell device at time of implant insertion, weeks 1, 4, and 12 after implant insertion. <br />Result: there was a statistically insignificant difference in stability values between direct metal laser sintering (DMLS) implants (test group) and conventional solid-structure (CSS) implants (control group) throughout the follow up periods except at 12 weeks follow up period there was a statistically significant increase in stability values in direct metal laser sintering (DMLS) implant (test group) compared to the conventional solid-structure (CSS) implants (control group). <br />Conclusion: Direct metal laser sintering (DMLS) implants showed higher secondary stability values than conventional solid-structure (CSS) implants.https://edj.journals.ekb.eg/article_72831_c3f9d717d65ecd71af9ba53f00f0c40c.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Comparative Study of the Antibacterial effect of MTA, Nano-MTA, Portland cement, AND Nano-Portland cement7017067283410.21608/edj.2019.72834ENYousra M.NashaatAssociate Professor of Endodontics, October 6 UniversityAhmed H.LabibAssociate Professor of Endodontics, Tanta UniversityNadaOmarResearcher, Restorative and Dental Materials Department, National research centerMostafaShakerLecturer in Endodontics, October 6 UniversityNeveen A.HelmyResearch of Clinical and Chemical Pathology At National Research CentreJournal Article20200222The root end filling materials antibacterial properties is a must nowadays as there is none of the available root canal filling materials can provide a hermetic seal.The aim of the current study isto compare the antibacterial effect of Gray Portland cement and white MTA angelus in the conventional and nano-particle forms. Agar diffusion test was used to examine the tested materials, where Enterococcus faecalis ATCC29212 (American Type Culture Collection 29212) cultured in agar BHI (brain heart infusion) in anaerobic condition at 37oCfor 72 hours.Then, the agar was added to 12 sterile petri plates and the prepared bacterial suspension was inoculated. Punch holes of 6 mm diameter were formed on each agar plate and each 3 plates were filled with the materials tested (Portland cement, Nano-Portland cement, MTA angelus, and Nano-MTA angelus). The results showed that conventional Portland cement has the highest antibacterial property, followed by Nano-Portland cement, MTA angelus, Nano-MTA angelus respectively with significant difference according to Kruskal Wallis ANOVA test followed by Mann-Whitney U test. https://edj.journals.ekb.eg/article_72834_eb5f26a0fa9d0219ad92cc7f4feafc34.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101EVALUATION AND COMPARISON OF THE INFLUENCE OF MICROWAVE AS A DISINFECTANT METHOD ON THE COLOUR STABILITY, MECHANICAL AND PHYSICAL PROPERTIES OF THERMOPLASTIC (BREFLEX) AND ACRYLIC RESINS DENTURE BASE MATERIAL7077247283810.21608/edj.2019.72838ENIman M.S.MatarLecturer, Department of Prosthodontics, Faculty of Dentistry, Pharos University, Alexandria, EgyptAhlam M.El-SharkawyProfessor, Department of Prosthodontics, Faculty of Dentistry, Alexandria University, EgyptJournal Article20200222Microwave radiation has been used for sterilization and disinfection of dental prosthesis which considered as an alternate method for chemical disinfectants.Aim: to evaluate the influence of microwave as a disinfection procedure on the colour ,the transverse strength and dimensional stability on the thermoplastic resin denture base and compare it with two types of conventional acrylic resin at different exposure times <br />Material and methods: 180 samples were made, 60 for each of the next tests (colour, transverse strength and dimensional stability) .The samples of each test, were subdivided into three groups each group has 20 samples according to the denture base material used (Breflex thermoplastic resin, heat cure and self cure). Each test were divided into four groups, one control and the other groups according to the time of microwave disinfection that were utilized (5,10,15 minutes) at 650 watt. Colour, transverse strength and dimensional stability parameters were measured with and without disinfection. Data were analyzed with ANOVA and Post-hoc Tukey’s tests with statistically significant at p ≤ 0.05 .<br /> Result: Microwave disinfection had no significant influence on the colour, the transverse strength beside the dimensional changes of all denture base materials at all the disinfection intervals, except it has a significant influence on the colour of heat cure for 15 minutes. Breflex showed a significantly increase in the flexural strength also, improvement in its fitness to the casts when compared with both heat and self cured resins after treated with microwave. <br />Conclusion: Microwave can be used safely for disinfection of all the denture base material except heat cure for 15 minutes. Breflex is the best due to it has no influence on its colour , increase the flexural strength, as well as dimensionally stable when compared with both heat and self cured acrylic resinshttps://edj.journals.ekb.eg/article_72838_ecd970ea0b3fafb6e76c6af499027804.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101The effect of framework material on partial overdenture supporting structures7257297284310.21608/edj.2019.72843ENSara FikryEl ShafeiLecturer of Removable Prosthodontics at the British University in EgyptJournal Article20200222Purpose: In this study the effect of two partial denture framework materials on the bone tissues surrounding a the implants, in an implant retained partial overdenture is compared. <br />Materials and Mehods: 12 partially edentulous patients with mandibular kennedy class I configuration were selected for this study. They were divided into two groups; Group 1 received a mandibular implant retained partial overdentures with a framework made of cobalt chromium. Group 2 received implant retained partial overdentures with a framework made of acetal resin. The results were evaluated using cone beam ct. <br />Results: The results showed that bone changes produced in metallic framework partial overdentures were greater than the changes produced in acetal resin framework partial overdentures. <br />Conclusion: Acetal resin partial denture framework produced less bone changes in the supporting structures than metallic framework partial dentures.https://edj.journals.ekb.eg/article_72843_fb1046ec9faf40d175daf560c22826d9.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101The effect of negative pressure on the antibacterial effect of herbal irrigant (An in vitro study)7317377284510.21608/edj.2019.72845ENElSaeedAbdel HafizLecturer of Endodontics Faculty of Oral and Dental Medicine Future UniversityAdelAbdelwahedLecturer of Endodontics Faculty of Oral and Dental Medicine Future UniversityJournal Article20200222Purpose: This study aimed to evaluate the antibacterial effect of Green tea as a root canal irrigant using Endovac irrigation System. Materials and Methods: for this study, 60 extracted human teeth were used. After their decapitation, they were instrumented using Universal ProTaper rotary files up to size F4 then separated into 2 set of groups according to the solution used in irrigation; Group A1: irrigated with 5.25% NaOCl Group A2: irrigated with Green tea (30 specimens in each group). We then subdivided each group into 2 subgroups according to the technique used for irrigation; Subgroup A: using conventional irrigation and Subgroup B: using Endovac irrigation system. Samples were sterilized and inoculated with Enterococcus faecalis(ATCC29212) for 48 hrs. After irrigation, microbial samples were collected, transferred to nutrient agar and incubated for counting of bacterial colony forming units (CFUs). The significance level was P≤ 0.05. Results: There was a statistically significant difference among the tested groups and subgroups in the mean scores of bacterial counts. Concerning the irrigating devices, there was statistically significant difference between conventional irrigation and Endovac system as Endovac showed higher antibacterial effect than conventional irrigation (P ≤ 0.05). Green tea showed statistical significant difference with Endovac system subgroup than conventional irrigation (P ≤ 0.05). Conclusion Endovac irrigation system was effective in eradication of E. faecalis from the root canals using either NaOCl or <br />Green tea.https://edj.journals.ekb.eg/article_72845_a7b02004e5622b04781795630472e576.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Color stability of Vita classical shade guide after artificial accelerated aging7397467284810.21608/edj.2019.72848ENMazenAttiaLecturer, Fixed Prosthodontics Department, Faculty of Dentistry, Beni Suef University, Beni Suef, EgyptLomayaGhanemAssociate Professor, Fixed Prosthodontics Department, Faculty of Dentistry, Misr International University, Cairo, EgyptTamerHamzaProfessor, Crown and Fixed Prosthodontics Department, Faculty of Dental Medicine, Al-Azhar University, Cairo, EgyptJournal Article20200222Statement of problem: If there is a noticeable color alteration in the shade guide, the result will be improper shade selection and consequently an unacceptable esthetic restoration. The effect of different weathering conditions on shade guides is still unclear.<br />Purpose: The purpose of this study was to determine the effect of artificial accelerated aging on the color stability of Vita classic shade guide.<br />Material and methods: The color parameters of the Vita classical shade guide tabs (n=160) were calculated before and after artificial accelerated aging (AAA) in a weathering machine using a spectroradiometer based on the CIE L*a*b* system. L*, a*, and b* coordinates and ΔE* were statistically analyzed using one-way analysis of variance followed by Bonferroni test (α=.05).<br />Results. There was a statistically significant difference for L*,a*, and b* coordinates for all specimens, creating darker specimens with a decrease in the L* coordinate value (P<0.001), and more reddish\yellowish specimens with an increase in a* and b* coordinate values (P<0.001). <br />Conclusion: Color changes were observed in all shade tabs after accelerated aging.<br />Clinical implications: Dentists should be aware of their shade guides after one year clinical service to achieve more esthetic results.https://edj.journals.ekb.eg/article_72848_71c38bd7486fb46f15782777fc961bae.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Wet and Dry Finishing and Polishing on Surface Roughness and Miarohardness of Bulkfill Resin Composites7477547285110.21608/edj.2019.72851ENRasha Hassan AliAfifiLecturer of Operative Dentistry, Conservative Dentistry Department, Future University in EgyptSara Mohamed HanyAlyLecturer of Operative Dentistry, Conservative Dentistry Department, Future University in EgyptJournal Article20200222Objective: The aim of this in vitro study was to evaluate surface roughness and microhardness of two bulkfill resin composites after wet and dry finishing. <br />Materials and methods: Two Types of resin composite materials SonicFill (Sonic-activated bulk-fill Nanohybrid resin composite) and X-tra fil (Bulk-fill micro- hybrid light-cured posterior resin composite) were used. Thirty samples were fabricated of each resin composite using a metal mold measuring (6mm x 4mm). Composites were applied to molds and placed between two transparent Mylar strips and pressed flat with a microscopic glass slide. A glass slab was placed on top of the upper Mylar strip and a constant pressure was applied. The samples were cured according to manufacturers’ instructions. The samples were divided into three groups (n=10). Group A: No finishing (control group), Group B: wet finishing under water coolant, and group C dry finishing. Surface roughness was evaluated using a stereomicroscope and microhardness was measured by Vicker’s hardness tester. Data were analyzed using one-way ANOVA (P<0.05).<br />Results: X-tra fil showed a statistically significant higher surface roughness mean values than Sonicfill in group A (control group) and group C (dry finishing) at p value ≤ 0.015 and ≤ 0.001* respectively, while with the wet technique there was no statistically significant difference in the surface roughness mean values between X-tra fil and Sonicfill at p value> 0.05. The control group showed the lowest microhardness mean values in both materials. Dry finishing showed the highest microhardness mean values among the groups (P<0.05). <br />Conclusion: Dry finishing and polishing increased the surface roughness and microhardness of X-tra fil (microhybrid) and (nanohybrid sonic activated) Sonicfill resin composites.https://edj.journals.ekb.eg/article_72851_09c30e10dea543c7b444e501c860c39d.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101The Effect of Different Post Space Surface Treatments on Push-out Bond Strength of Fiber Posts Adhesively Bonded to Root Canal Dentin7557617285310.21608/edj.2019.72853ENMostafa ElSayedAbouShahbaLecturer of Fixed Prosthodontics, Fixed Prosthodontics Department, Future University in EgyptJournal Article20200222Aim: The purpose of this study was to analyze the effect of different post-space preparation and irrigation protocol on bond strength of resin cement to root canal dentin. <br />Methods: Teeth were endodontically treated. After post-space preparation every sample was assigned to one of three groups. In each group different preparation and irrigation protocol was performed as follows: 0.9% saline solution (Group A), 37% phosphoric acid etch which was activated with an ultrasonic tip then rinsed with 10 mL of 0.9% saline solution (Group B), and manipulated with abrasive diamond tapered stone with round end then rinsed with 10 mL of 0.9% saline solution for 10 seconds (Group C). Two parts (coronal and apical) of each sample were analyzed by push out test. Push out bond strength measurements were recorded. <br />Results: For coronal part, group C showed the highest significant values followed by Group B followed by Group A. For apical part, group B showed the highest significant values followed by Group A followed by the Group C. For the total; Group B and C showed highest value compared to group A with insignificant difference between B and C. For comparison between Coronal and Apical; Apical section showed a significant lower value compared to Coronal section for all tested groups at p≤0.05. <br />Conclusions: Phosphoric acid etch activated with an ultrasonic tip then rinsed with saline solution appeared to be the best mode of preparation and irrigation when self-etch bonding is used since the adhesion interface is made by a thick smear layer.https://edj.journals.ekb.eg/article_72853_a09a805c1e4b8aab139616ef721a097d.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Fracture load of all-ceramic crowns after two different conditioning techniques7637707285510.21608/edj.2019.72855ENShaimaa Ahmed Abo El-FaragIbraheimLecturer at Department of Fixed Prosthodontics, Faculty of Dentistry, Mansoura University, EgyptJournal Article20200222Purpose: This study investigated influence of two conditioning methods and two luting cements on the fracture load of all-ceramic crowns. <br />Materials and methods: A total of thirty-two CAD-CAM all-ceramic crowns, (Vita Mark II) were constructed on human upper premolars indicated for extraction and collected from department of oral surgery, faculty of dentistry, Mansoura University. The intaglio surfaces of 16 crowns were treated using acid (4.9% HF) with silane application. The other 16 crowns were conditioned using Monobond Etch & prime in one step. Each group divided into 2 subgroups (n=8) according to used type of luting cements. Self adhesive resin cement (Rely X U200) or multistep adhesive resin cement (Mutilinik Automix) were used for crowns cementation to appropriate teeth. Crowns were kept in water for 3 months but after cementations by one hour. Universal testing machine was used to record the fracture load for crowns (N). <br />Results: Means fracture load of groups luted with multistep adhesive resin cement were significantly higher than means fracture load of test groups luted using self adhesive resin cement regardless of conditioning techniques used (P < 0.05). Means fracture loads of other test groups were not statistically significant (P >0.05). <br />Conclusions: Two techniques used for conditioning of Vita Mark II crowns did not affect significantly fracture load of these crowns. Multilink adhesive resin cement improved fracture loads of Vita Mark II crowns compared to RelyX U200.https://edj.journals.ekb.eg/article_72855_3dc0355a193f1a49b7445c6e60556d37.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Prevalence of Failed Inferior Alveolar Nerve Block (IANB) in Achieving Pulpal Anaesthesia in Mandibular Molars with Symptomatic Irreversible Pulpitis7717767285910.21608/edj.2019.72859ENMohammedHowaitAssistant Professor, Department of Endodontics, King Abdulaziz University, Faculty of Dentistry, Jeddah, Saudi ArabiaGhadeer I.BasunbulAssistant Professor, Oral and Maxillofacial Rehabilitation Department, King Abdulaziz University, Faculty of
Dentistry, Jeddah, Saudi ArabiaJournal Article20200222Introduction: Patient comfort during root canal treatment is immense for patient cooperation and endodontist efficiency. Establishing the high prevalence of failure of IANB injections in providing pulpal anaesthesia, will most likely support the investigation of supplemental techniques to ensure patient comfort. <br />Objectives: The study aimed to evaluate the prevalence of failed Inferior Alveolar Nerve Block (IANB) injections in achieving pulpal anaesthesia in mandibular molars diagnosed with symptomatic irreversible pulpitis when administered alone. <br />Methods: This study involved fifty patients, diagnosed with symptomatic irreversible pulpitis in their mandibular first and second molars. IANB injection using 2% lidocaine with 1:100,000 epinephrine was administered to anesthetize the acutely inflamed teeth before commencing root canal treatment. Lip and tongue numbness was checked subjectively after injection to ensure successful IANB injection. Objectively, cold test was performed after 15 minutes and pain level was recorded using Visual Analogue Scale (VAS). Success was defined as no pain response by (VAS) during cavity preparation, endodontic access, or initial instrumentation. <br />Results: Although, majority of patient (96%) expressed surrounding soft tissue numbness, only 73% did not feel any pain during initiating root canal treatment. <br />Conclusions: IANB injection alone is not enough to provide profound pulpal anaesthesia in acutely inflamed mandibular molars; therefore, supplemental injections are required to achieve patients comfort during treatment.https://edj.journals.ekb.eg/article_72859_a4fd3bf6a66d97edd04d3a131e64b913.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Stress distribution around titanium-zirconium narrow-diameter implants retaining mandibular over dentures with Novaloc versus locator attachment systems. A three-dimensional finite element analysis7777857286110.21608/edj.2019.72861ENEatemad R.TahaAssociate Professor, Removable Prosthodontics Department, Faculty of Oral & Dental Medicine, Ahram Canadian
University, Egypt.Journal Article20200222Statement of the problem: The use of narrow diameter implant to retain an implant overdenture could be the treatment of choice to restore resorbed mandibular ridge, however its success or failure depends on the amount of stresses transferred to the surrounding bone via the selected attachment system. The goal of this study was to evaluate the stress distribution around two narrow- diameter titanium-zirconium implants retaining mandibular overdenture with novel Novaloc attachment system in comparison with traditional locator attachment using 3 D finite element analysis<br />Materials and methods: Two 3D finite element models were prepared simulating completely edentulous mandibular ridge with complete overdentures supported by two narrow diameter implants in the canine region. Model 1,represented implants with locator attachment while Model 2, represented implants with Novaloc attachment. The models’ components were created on a commercial CAD/CAM package then imported to finite element software. Load of 100 N was applied on molar area of the mandible vertically and oblique Load of 50 N at 30º and 45º angle. <br />Results: Within the limitations of this research, similar deformations and stresses distributions were reported in the bone and implant complex with a little more stresses in the Novaloc system. All values found were within acceptable physiological limits of the studied parts. Stress received by the PEEK matrix of the Novaloc attachment was significantly less than that of the locator nylon cap. <br />Conclusion: Within the limitations of this in-vitro study it may be concluded that locator attachments may provide little less stress on the bone and implant complex in implant retained overdenture than did the Novaloc attachment. However, the lifetime of the flexible caps may be longer for Novaloc system in comparison to locator ones.https://edj.journals.ekb.eg/article_72861_2f15c58e71b87e134c9605342f55469a.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Evaluation of Antibacterial Effect of a new root canal irrigating Formula of Salvadora persica Roots Nanoparticles. An In vitro Study7877927286310.21608/edj.2019.72863ENMoatazbellah A.AlkhawasAssociate Professor of Endodontics, Faculty of Dental Medicine, Al-Azhar University, Cairo, EgyptRehabAbdelmonemAssociate Professor of Pharmatheuticals, Faculty of Pharmacy, MSA, EgyptMohammedE RokayaLecturer of Endodontics, Faculty of Dental Medicine, Al-Azhar University (Assuit Branch), EgyptJournal Article20200222Aim: The study was done to evaluate the antibacterial effect of a new formula of Salvadora persica roots Nanoparticles as compared to sodium hypochlorite irrigating solution. Methods: A total of 20 recently extracted single-rooted, with single root canal were selected to be used in the study. Decapitation of the selected teeth for 18 mm length standardization was done. The root canals were initially instrumented using manual instrumentation till reach file size 25 for apical preparation. Sterilization of the samples was done using gamma rays. Following sterilization, the samples were divided into two groups (n=10) according to the tested irrigating solution used as follow; Group H: For Salvadora persica roots nanoparticles. Group S: For 2% sodium hypochlorite. The chemo-mechanical preparation was accomplished using Revo-S rotary system in a crown-down technique with the file sequence that was recommended by the manufacturers. Pre and post-irrigation counting of the E. Fecalis was done by determining the Colony Forming Unit. Results: The highest mean value of percentage changes in bacterial reduction was found in (Group S) (95.99%) and the least bacterial reduction percentage was found in (Group H) (82.83% with no statistically significant difference between both groups (P-value=0.068). Conclusion: Under the condition of this study, the new formula of Salvadora persica roots nanoparticles is a promising irrigating solution of herbal origin instead of the synthetic irrigating solution.https://edj.journals.ekb.eg/article_72863_a0df996a62a93a4ef5d34fef5a85c054.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Peri-Implant Bone Loss and Esthetic Outcome of Single-Tooth Implant in Patients with Type 2 Diabetes7938027286610.21608/edj.2019.72866ENWalidAl-ZordkAssistant Professor, Fixed prosthodontics Department, Faculty of Dentistry, Mansoura University, Mansoura, EgyptSallyAwadAssociate Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Mansoura University,
Mansoura, EgyptSamahSakerAssociate Professor, Fixed prosthodontics Department, Faculty of Dentistry, Mansoura University, Mansoura, EgyptJournal Article20200222Background: Esthetic outcome associated with dental implant in type 2 diabetic patients remained uninvestigated.<br />Purpose: To study the impact of type 2 diabetes mellitus on clinical and esthetic outcomes of single-tooth implant following delayed implant installation in the anterior maxilla. <br />Materials and Methods: Forty patients were recruited for this investigation. Half of patients were previously diagnosed with controlled type 2 diabetes mellitus (group D) and the remaining (n=20) were healthy individuals (group H). All implants were inserted in the anterior part of the maxilla either with sufficient bone volume /or with labial bone defect. Evaluations of soft and hard-tissue changes were checked during the follow-up period up to 24 months. <br />Results: Significant loss in marginal osseous tissue was observed during 24 months of evaluation with respect to diabetic (p=.001) regardless the bone augmentation procedure used, while group H showed significant loss at 6 months of evaluation followed by non-significant changes of the marginal bone level till 24 months. Mean PES and WES scores did not diverge significantly among groups D and H (p>.05).<br />Conclusions: Single tooth dental implants can remain functionally and esthetically acceptable in type 2 diabetic patients in a manner similar to healthy patients provided carful controlling and maintaining of blood glycemic level.https://edj.journals.ekb.eg/article_72866_f1d1c498413bf322b4391aa71b2b0d03.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Preparation Design on Fracture Resistance and Failure Mode of Root Canal Treated Maxillary Premolars Restored with Onlay Restorations8038117286710.21608/edj.2019.72867ENWalidAl-ZordkAssistant professor, Department of Fixed Prosthodontics, Mansoura University, Mansoura, Dkahlia, EgyptJournal Article20200222Purpose: Cusp fractures are among the major reasons for the extractions of root-treated teeth. With the intention of increasing information about the mechanical behavior of minimally invasive cusp coverage restorations, the aim of current study was to evaluate the fracture resistance and failure modes of endodontically treated maxillary premolars restored with onlays employing various cusp reduction designs (anatomic, horizontal and beveled) to identify the optimum design and to assess whether these designs influence the restorable fracture rate.<br />Materials and methods: Fifty defect-free maxillary premolar teeth were divided into 5 groups: onlay with anatomic occlusal reduction design (OA), onlay with horizontal occlusal reduction design (OH), onlay with beveled occlusal reduction design (OB), full-coverage crown (CR) and non-restored sound teeth (NR). In OA, OH, OB and CR groups, the access cavities were sealed using bonded composite after endodontic treatment. For OA, OH and OB groups, cusps were prepared with anatomic, horizontal and beveled designs. Except for NR group, all teeth were restored with resin-infiltrated ceramic restorations. After thermal aging for 10000 cycles between 5°C and 50 °C, all specimens were submitted to compressive axial load at a crosshead speed of 1 mm min-1 till failure. The data were analyzed using ANOVA test.<br />Results: The highest load to fracture values (N) was recorded in control non-restored group (1657±167.7N), followed by CR, OA, OB and OH groups where the mean values were 887.5±40.3, 789.4±54.8, 722.2±46.2 and 634.8±74.2N respectively. Significant differences were found among fracture values of test groups (p<.05). The intact teeth predominantly fractured with favorable fracture patterns followed by CR group; while both OB and OH groups showed the heights non-favorable pattern of fracture. Group OA represented moderate percentage of favorable fracture.<br />Conclusions: Root treated teeth restored with anatomic cusp reduction design displayed greater fracture resistance and greater rates of restorable fractures than root treated teeth submitted to horizontal and beveled reduction deigns.https://edj.journals.ekb.eg/article_72867_bf5d0f732c6507e699c5d7db654ffbf3.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101EFFECT OF NANOPARTICLES MODIFIED GLASS IONOMER CEMENT ON THE COLOUR AND SHEAR BOND STRENGTH OF LITHIUM DISILICATE CERAMIC8138247286810.21608/edj.2019.72868ENShereen KotbSalemLecturer of Fixed Prosthodontics. Faculty of Dentistry, October 6 UniversityRasha SayedAsaadOral and Maxillofacial Prosthodontic Department, Faculty of Dentistry,King Abdulaziz University, Jeddah,
Kingdom of Saudi ArabiaJournal Article20200222The effect of glass ionomer cement modified by nanoparticles on the bond strength and colour of lithium disilicate ceramic was studied. Glass ionomer cement modified by nanosilver or nanogold, glass ionomer cement and IPS e.max CAD A2 were used. Thirty e.max CAD discs were constructed. The samples were divided into 3 groups, the first group, 10 samples (control group) used non modified glass ionomer cement (GIC), the second and third groups, 10 samples each used modified glass ionomer cement : nano silver (NSGIC), nanogold (NGGIC). The samples were then subdivided according to the test to which they will be subjected: colour test - shear bond strength test (5 samples each).The samples subjected to colour test were cemented to a composite discs with a shade A2 while those subjected to shear bond strength test were cemented to dentine, using the 3 tested types of glass ionomer. <br />Results showed that ΔE of all the tested samples recorded values in the range of clinical acceptability. NGGIC group showed less ΔE than NSGIC group compared to the control group. Also, the results showed no statistical significant difference in shear bond strength between the control group (GIC) and the two experimental groups (NSGIC) and (NGGIC). <br />Conclusion: The addition of nanoparticles to glass ionomer cement resulted in ΔE within the clinical acceptance. Also, they showed no significant difference as regards to shear bond strength.https://edj.journals.ekb.eg/article_72868_1bf5f7b8f9f02a287638432cabae5ae6.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Comparative Evaluation of the Antibacterial Effect of Triple Antibiotic Paste Versus Propolis as Intracanal Medicament8258307286910.21608/edj.2019.72869ENElsaeedAbdel HafezLecturer of Endodontics, Faculty of Oral and Dental Medicine, Future University- EgyptAmgad H .SolimanLecturer of Endodontics, Faculty of Oral and Dental Medicine, Future University- EgyptJournal Article20200222Purpose: This study aimed to compare between Propolis and Triple Antibiotic Paste as root canal medicaments in eradication of Enterococcus faecalis. Material and Methods: for this study, 60 extracted human teeth were used. After their decapitation, they were initially instrumented to reach 20 K-file, later they were separated into 2 sets according to the medicament used; Group A1: Triple antibiotic paste Group A2: Propolis paste (30 specimens in each group). After sterilization of all samples inoculation was performed with Enterococcus faecalis (ATCC29212) over a period of 21 days. Preparation of all samples was done using Step- back technique to reach #50 file, irrigation using sodium hypochlorite solution of 2.6% concentration and EDTA, then intracanal medicaments were applied. First sample (S1) was collected after inoculation of bacteria into root canals. Second sample (S2) was collected after undergoing instrumentation and irrigation. Third sample (S3) was taken following application of medicament. Fourth sample (S4) was taken following application of sterile cotton pellet and temporary restoration for seven days. BHI agar was used for culturing of samples then went under incubation to count CFU’s. Results: There was a significant difference between different samples where (p ≤ 0.05) and there was a continuous decrease of (mean ±SD) value starting from (S1) till (S4). Pairwise comparisons for both medicaments showed all samples to be significantly different from each other. Conclusion: Antimicrobial activity of Propolis against E. faecalis was found to be greater than that of TAP and can be used as a short-term intracanal medicament.https://edj.journals.ekb.eg/article_72869_518cf57a7d5413670935f81abdf9c4db.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101ANTIBACTERIAL EFFECT OF SALVADORA PERSICA ROOTS NANOPARTICLES VERSUS SODIUM HYPOCHLORITE AS ROOT CANAL IRRIGATION8318367287110.21608/edj.2019.72871ENElsaeedAbdel HafezLecturer of Endodontics, Faculty of Oral and Dental Medicine ,Future University- Egypt.Amgad H .SolimanLecturer of Endodontics, Faculty of Oral and Dental Medicine ,Future University- Egypt.Journal Article20200222https://edj.journals.ekb.eg/article_72871_7cb0585ab824e4edffd160ffae4a2f09.pdfThe Egyptian Dental Association (EDA)Egyptian Dental Journal0070-948465Issue 1 - January (Fixed Prosthodontics, Dental Materials, Conservative Dentistry & Endodontics)20190101Effect of Artificial Saliva, Bioactive Glass and Fluoride Varnish on Micro-hardness and Micro -shear Bond Strength of Demineralized Enamel Surface8378477287210.21608/edj.2019.72872ENHebatallah M.TaherAssociate Professor of Conservative Dentistry, Cairo University and October University for Modern Science and ArtMohamed FouadHaridyAssociate Professor of Conservative Dentistry, Cairo University and British University in EgyptJournal Article20200222Objectives: the aim of this study was to compare the effect of 3 different remineralizing agents on microhardness and microshear bond strength of demineralized enamel surface.<br />Materials and methods: A total of 50 teeth were divided into five groups (10 each) that were summarized as follows: Group 1: sound unprepared teeth (base line control); Groups 2: demineralized enamel (negative control). Group 3: demineralized enamel stored in artificial saliva for one month. Group 4: demineralized enamel treated by bioactive glass (sylic powder). Group 5: demineralized enamel treated by fluoride varnish (positive control). Five samples from each group were used to test the micro-hardness and the other five samples were used to microshear bond strength.<br />Results: A statistical significant difference was found in microhardness between the sound enamel group and both of the demineralized enamel and the fluoride varnish test groups ,meanwhile no statistically significant difference was found between sound enamel group and both of the artificial saliva test group and the Sylc powder test group. Also, there was a statistically significant difference in microshear bond strength between sound enamel and each of demineralized enamel, demineralized enamel with artificial saliva, demineralized enamel with Sylc powder and demineralized enamel with Fluoride varnish.<br /> Conclusion: The two remineralizing agents; bioactive glass and artificial saliva are capable of enhancing microhardness and micro shear bond strength of demineralized enamel more effectively than fluoride varnish .https://edj.journals.ekb.eg/article_72872_476a6fc44dde5708e28a3f9e63e9d901.pdf