الكليات الإنسانية
الكليات العلمية
الكليات الصحية
العمادات
المراكز
الدوائر الإدارية
مكتب ضمان الجودة و الاعتماد
المرافق
الخدمات
بوابة الطالب
بوابة الموظف
التقييم والتغذية الراجعة
النماذج
Authors : Mona I. Riada*, Wael M. Gamal, and Ahmad S. Morsy
Abstract :Color matching between the resin composite and the teeth is the most aimed target by the patient to evaluate the quality of the treatment. The aim of this study was to investigate the ability of the uni-shade restorative material to match the tooth shade and the blending effect of the single shade structurally colored universal resin composite. Materials and methods disc shaped specimen (6×2 mm) were prepared from Omnichroma® single shade resin composite. Color shade was recorded for 10 freshly extracted premolars by Easyshade® according to CIE Lab system. Standardized class V cavities (4×2×1.5 mm) were prepared on the buccal surface of each tooth away 0.5mm from the CEJ. Cavities were then restored with resin composite, cured for 40s, and their color was recorded after 24 hours storage in distal water. Two tests have been done; the first was to determine the differences of the color parameters between disc and resin composite in teeth (T1). The second was to record the change in color between the sound teeth and the resin composite in teeth (T2). The color change data statistically analyzed using paired t-test. It was considered statistically significant at (P=0.05). Results All color parameters in the two tests showed significant changes except (ΔL) in T2 which showed nonsignificant differences. The specimens showed decrease in lightness and showed shifting toward the green and yellow direction, while in T2 they became lighter than the teeth and directed toward the green and blue scale. Conclusion OMNICHROMA single shade resin composite matches the shade of enamel
Keywords : Blending effect, Color match, Color parameters, Single shade resin composite
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Authors :Ghada A. Salem1, Wael Mohamed Gamal2, Omnia A. Elhiny3
Abstract :Aim: The aim of this study was to investigate the adhesive efficiency of preheated nanohybrid composite in bonding orthodontic brackets compared to Transbond XT and flowable composite. Material and Methods: Forty-five orthodontically extracted premolars were randomly divided into 3 groups. For group I, Transbond XT was the adhesive of choice, for group II; flowable composite, while for group III preheated nanohybrid composite was used. All the samples were exposed to thermocycling for 1000 cycles and then the shear bond strength and the adhesive remnant index (ARI) were determined for each group. Results: There was a statistically significant difference between group 1 and the other two groups (p<0.001). There was no statistically significant difference between group 2 and group 3 (p=0.896). ARI scores 2 and 3 showed the highest frequency in all groups. Conclusion: Despite having a clinically acceptable bond strength, the short manipulation time of the preheated nanohybrid composite presented a limitation for its use and might have affected its bond strength. Transbond XT showed the highest bond strength while flowable composite displayed the lowest bond strength
Keywords : Flowable composite, preheated nanohybrid composite, Transbond XT, shear bond strength
Authors : Wael Gamal, Ahmed Safwat, Ahmed Abdou
Abstract :BACKGROUND: Color mismatch between tooth structure and restoration is a common reason for restoration replacement. This is due, in part, to the diverse chemical structure of both substrates, which display a different staining potential resulting in a significant color mismatch. AIM: The aim of the study was to evaluates the color change of single shade resin composite and compare it to fibrous-filled resin composite (FRc) after storage in coloring beverages. METHODS: Trapezoidal Class V cavities were prepared on the buccal and lingual surfaces of 30 premolars. Cavities on the buccal surface were restored with Omnichroma (ON) and palatal surface with FRc. Specimens were stored on water, tea, and coffee solutions for 24 h and 72 h. The color change was measured after each immersion time and statistically analyzed using three-way analysis of variance (ANOVA) (α = 0.05). RESULTS: Three-way ANOVA showed that different materials had a significant effect on both ΔL and Δa (p < 0.001). For both materials, ON in coffee showed the highest Δb values when compared to FRc for the same period. No difference between ON and FRc when stored in tea for 24 h and 72 h. CONCLUSION: Structural color property of ON can enhance the color perception of restoration to compensate for any color change after consuming coloring food and beverages
Keywords : Chameleon effect; Discoloration; Structural colors; Fiber reinforced composite
Authors :Ahmed Magdy Sayed and Wael Mohamed Gamal
Abstract :Tooth brushing of the esthetic restorative materials may results in their wear and subsequently negatively affecting their biological, esthetic and mechanical properties. The aim of the study was to compare the effect of oscillating-rotating (OS) and the sonic (V) power-driven toothbrushes on the wear of three different restorative materials. Materials and methods: Three restorative materials were used; nano-hybrid composite Filtek™ Z250 XT, bulk fill resin composite Tetric N- Ceram Bulk Fill and highly viscous glass ionomer restoration Ketac™ Universal Aplicap™. With a total of 42 samples (10x2 mm), 14disc shaped samples were prepared from each material and randomly divided into two groups then subjected to wear with the two electric toothbrushes (n=7) for 60 minutes under toothpaste slurry. Change in surface roughness (Ra) and weight loss before and after wear testing was recorded and subjected to one-way ANOVA followed by Tukey post-hoc tests (with significance level P ≤ 0.05) to reveal the significant difference. Results: The highest Ra and weight loss values were recorded in samples subjected to wear by V toothbrush in three tested materials. However, there was no statistically significant difference between the tested materials with OS toothbrush. Conclusion: OS and V electric toothbrushes have the same effect on the surface topography of the tested restorative materials
Keywords : oscillating toothbrush; sonic toothbrush; wear; weight loss; Bulk-fill resin Composite
Authors : Wael Mohamed Gamal and Ahmed Magdy Sayed
Abstract :Objectives: This study evaluated the effect of incorporating Graphene oxide nanoparticles on the post-gel shrinkage strain and degree of conversion of resin composite restorative material. Materials and methods: Graphene oxide nanoparticles was synthetized and incorporated within a nanohybrid resin composite (Filtek™ Z250 XT). 20 specimens (7x4x2 mm) were fabricated for polymerization shrinkage and divided into 2 equal halves. 10 specimens were fabricated without incorporation with Graphene oxide nanoparticles (the control group; group 1), while the other half was incorporated with 2% concentration by weight and referred to group 2. The post-gel shrinkage strain was measured by strain gauge technique. The degree of conversion was measured using a Fourier Transform Infrared (FTIR) spectrometer. Similar groups specimens were prepared by polymerizing the material in a disc-shaped split white Teflon mold 2 mm thick and 4 mm in diameter. Ten disc-shaped specimens were prepared for each experimental condition. The resultant data were subjected to independent T-test (P≤0.05) to reveal the statistically significant difference. Results: The incorporation of Graphene oxide nanoparticles significantly reduced the post-gel shrinkage strain. On the other hand, the degree of conversion reported no significant difference between the two groups. Conclusion: Addition of Graphene oxide nanoparticles to resin composite restorative material positively affect the polymerization shrinkage while maintaining the degree of conversion
Keywords :Graphene oxide NP, resin composite, polymerization shrinkage, degree of conversion
Authors : Wael Mohamed Gamal , Shaimaa Ahmed Alrafee and Ahmed Magdy Sayed
Abstract :Objectives: This study assessed the antibacterial effect and the shear bond strength of self-etch adhesive after incorporating Graphene oxide nanoparticles. Materials and methods: Graphene oxide nanoparticles was synthetized and incorporated within a self-etch adhesive (Quadrant Uni-SE-Bond) with 0% control group (without Graphene) (group I), 2% (group II) and 5% (group III). The antibacterial effect was evaluated against S. Mutans using agar well diffusion method. 24 holes (n=8) with a diameter of 6-8 mm were performed and the inhibition zone was evaluated in millimeters after 24 hrs. For shear bond strength, 12 premolars were sectioned horizontally to expose dentin and to obtain 24 specimens for assessing the bond strength (n=8). Composite cylinders (2x2 mm) were bonded to the dentin and subjected to shear bond strength using universal testing machine. Results: The incorporation of Graphene oxide nanoparticles into self-etch adhesive showed a significantly dose-dependent antibacterial effect. On the other hand, the shear bond strength reported no significant difference between the three groups. Conclusion: Addition of Graphene oxide NP to self-etch adhesive produced an antibacterial effect without affecting the bond strength
Keywords :Graphene oxide NP, self-etch adhesive, antibacterial, shear bond strength.
Authors : Wael Gamal1, Ahmed Abdou2 and Ghada A. Salem3
Abstract :Aim: To evaluate the effect of using different short fiber-reinforced resin composites on fracture resistance and flexural strength of endodontically treated tooth and compare it with nano-filled resin composite. Methods: Sixty human premolars were used for the fracture resistance test. Root canals were sequentially enlarged using a Pro-taper system from SX to F3 and obturated with Gutta-percha. Mesio-Occluso-Distal (MOD) cavities were prepared in all teeth. Teeth were then divided into 3 groups (n = 20 each) based on the type of resin composite. Group 1: Alert fiber-reinforced resin composite, Group 2: EverX Flow fiber-reinforced resin composite, and Group 3: Z350 nano-filled resin composite. Each group were subjected to a load till fracture using a universal testing machine to measure the fracture resistance. For the flexural strength test, 10 specimens from each material were prepared and 3- point bending tests were performed. The results of both tests were analyzed by using Weibull analysis. Results: Teeth restored with Ever X fiber-reinforced resin composite conveyed the highest significant fracture resistance and flexural strength value when compared to the other two materials. Conclusions: Short Fiber-reinforced resin composite can be considered a better choice for the restoration of MOD cavities in endodontically treated teeth
Keywords :Fracture resistance, Endodontic treated teeth, Fiber-reinforced resin composite
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