Heba Bahgat Abdel- Mohsen

Aim: This research was formulated to investigate the fracture resistance of premolars restored using preheating thermo-viscous, sonic fill, bulk injectable, and incrementally packed nano-hybrid resin composite materials. Materials and methods: Sixty extracted premolars were selected and standardized class II MOD cavities were prepared. Teeth were distributed randomly into six groups according to restoration techniques used: Group 1 (intact sound teeth; positive control, Group 2 (prepared cavities; negative control), Group 3 (VisCalor Bulk fill; VCB), Group 4 (SonicFill 3; SOF), Group 5 (Herculite™ XRV Ultra™; HXU), and Group 6 (G-aenial bulk injectable; GBI). All prepared teeth were then aged by thermocycling for 5000 cycles and tested for fracture resistance. The mode of fracture was identified using a stereomicroscope and scanning electron microscopy. Results: All tested MOD restorations failed differently. The resin composite material type had a considerable impact on all specimens' load-bearing capacity (p<0.05). A statistically significant difference (p< 0.05) in the fracture resistance values of MOD cavities restored with all tested types of resin composites was recorded. No significant difference was reported between SOF and HXU according to one-way ANOVA (p=0.800). Conclusion: GBI represents an acceptable option used for direct restorations without a superficial layer of conventional composite covering layer compared to low or high-viscosity bulk fill materials. Injectable bulk fill composites represent an optimum selection over other nanohybrid packable bulk fill materials in restoring mesio-occluso-distal cavities.

Aim: This study's objective was to investigate the impact of gut-friendly supplements ‎on the surface roughness of bulk-fill resin composites. ‎ Materials and methods: A hundred composite discs (10 mm × 2 mm) were prepared ‎from a bioactive surface pre-reacted glass (S-PRG) filled composite Beautifil Bulk ‎Restorative (BBR) and nanohybrid Tetric N-Ceram bulk (TNB) restorative resin-‎composite. Ten discs were examined per group after 24 hours without treatment ‎‎(baseline). Then, each group was split up into four subgroups (n=10) based on the ‎immersion media: distilled water (control), probiotics, prebiotics, and pro/prebiotic ‎media. Specimens were submerged for 10 minutes/day for 1 month. A 3D non-contact ‎optical Profilometer was utilized to measure surface roughness (Ra). Three subsequent ‎measurements in each specimen were taken to calculate the mean surface roughness ‎values. Data were calculated and statistically analyzed using Two-way ANOVA ‎followed by Tuckey’s post hoc test (P ≤ 0.05). ‎ Results: The results showed that the supplements-immersed surfaces of all tested ‎materials were roughest. There was a statistically significant difference between TNB ‎and BBR immersed in prebiotic and baseline at p=0.003 and p=0.022, respectively. The ‎BBR specimens immersed in prebiotic solution had the highest surface roughness value ‎‎(10.57 ± 0.90 µm). ‎ Conclusion: The S-PRG and nanohybrid composite resins' surface roughness may be ‎adversely affected by dietary supplements that are gut-friendly. BBR composite resin ‎was the one that suffered the most damage in surface roughness analysis after storage in ‎the prebiotics solution.‎

Aim: To compare the accuracy and reliability of three shade selection protocols: visual ‎shade selection, visual shade selection with a light-correcting device equipped with a ‎polarization filter, and digital shade selection using VITA Classical (VC) and VITA 3D ‎Master (V3D) shade guides on natural teeth. Materials and methods: This study compared ‎the accuracy of three shade selection protocols: visual selection under daylight (VSS), ‎visual selection with a light-correcting device using a polarization filter (VWL), and digital ‎selection (DSS) using the VITA Easyshade Advance spectrophotometer. Two experienced ‎dentists used the spectrophotometer to determine the upper right central incisor and canine ‎reference shades. One hundred participants selected shades for these teeth using the VITA ‎Classical and VITA 3D Master shade guides under the three protocols. Shades matching the ‎reference were recorded as correct, and the accuracy of each protocol was evaluated ‎comparatively. Results: A statistically significant difference was reported between VC and ‎V3D, with the three tested shade selection protocols with p<0.001. No statistically ‎significant difference was recorded between the three shade selection protocols while using ‎VC and V3D, with p=0.261 and p=0.503, respectively. A statistically significant difference ‎resulted between all shade selection protocols’ preferred answers, with the highest number ‎of answers found in DSS (72%) followed by VWL (17%) and (VSS) which recorded the ‎least number of answers (11%) (p<0.001). No statistically significant difference was ‎observed between males and females regarding the preferred technique (p=0.580). ‎ Conclusion: DSS demonstrated the highest accuracy and participant preference, ‎highlighting its potential as the most reliable shade selection protocol. ‎

Background: Individuals seek out cosmetic dentists not so much for improved dental function or overall health but rather to improve the appearance of their teeth and gain more social acceptance. This study aimed to evaluate how dental students at King Abdul-Aziz University (KAU) perceived smiles based on their gender. Methods: The study included two hundred students with clinical experience from the College of Dentistry, KAU. The data were collected using a three-part validated questionnaire. The first part included socio-demographic items; the second part included two close-ended questions regarding aesthetic characteristics; and the third part consisted of perception to seventeen photos of digitally manipulated smiles to be assessed using a numeric rating scale (NRS), (1, best; 5, worst). Results: The first facial feature to catch the attention of most students was a smile, which was followed by the eyes. Almost 98% of the participants considered the smile one of the most important features of facial aesthetics. According to Faradeni research, men valued their gingival smile characteristic (p=0.013) and teeth color (p=0.001) substantially higher than women. Conversely, females had higher crucial margin discrepancy (p=0.038) and convex occlusal plane (p>0.001) than males. Conclusion: When it comes to the gingival smile, teeth color, and the initial facial feature that attracts the eye, women perceive smiles as more aesthetically pleasing than men. Gingival margin discrepancy and convex occlusal plane were more critical in males than females. Understanding smile aesthetics from the perspective of dental students enhances patient care, education, and overall treatment outcomes.

Objective The current research aimed to evaluate the histopathological pulpal alterations in dogs' teeth following direct pulp capping using either mineral trioxide aggregate (MTA) or human placenta extract (HPE). Materials and Methods Forty-eight incisors with mature apices from four dogs were involved. The teeth were randomly allocated to three groups (n = 16) based on the material utilized for direct pulp capping: MTA, HPE, and Teflon as the negative control group. All involved teeth were capped and restored at the same session. Each group was subsequently divided into two subgroups (n = 8) based on the post treatment evaluation period: 2 and 4 weeks. The histopathologic changes in each specimen's pulp tissues, including pulp inflammation, hyperemia, necrosis, and dentin bridge development, were assessed. Then, all the data were statistically analyzed using chi-square, t-test, and one-way analysis of variance (p < 0.05). Results At 2 weeks, chronic inflammation was observed in 100% of MTA and 50% of HPE subgroups with a significant difference between them whereas the remaining 50% exhibited no inflammation. In contrast to Teflon that showed acute inflammation, remission of inflammation was time-dependent at both MTA and HPE subgroups as there was a substantial difference between the 2- and 4-weeks evaluation periods within the same group. However, throughout the initially observed 2 weeks, all subgroups exhibited essentially no complete calcified bridge; at 4 weeks, all MTA and HPE subgroups developed dentin bridge formation, with a significant difference between them regarding its thickness. Conclusion HPE is a promising pulp-capping material inducing less intense chronic inflammation accompanied with thicker dentine bridge formation in comparison to MTA.

Purpose: This research aimed to investigate fracture resistance of endodontically treated maxillary premolars restored using preheated thermo-viscous and fiber-reinforced bulk fill resin composite, in vitro.Methodology: Sixty sound human maxillary premolars were selected and divided randomly into 6 groups of ten teeth each (n = 10). Group 1; is the positive control with sound unprepared teeth (P), Group 2; is the negative control in which Mesio-occluso-distal (MOD) cavities were left unrestored (N), Group 3; includes the teeth restored by incremental packing with conventional nanohybrid composite (ChP), Group 4; includes teeth restored with short fiber reinforced bulk fill composite (EF), Group 5; includes teeth restored with preheated thermo-viscous bulk fill composite (VB), and Group 6; includes teeth restored using packable bulk fill composite (XF) Tested restorative materials were bonded with a universal adhesive in self-etch mode. Teeth were kept in distilled water for 24 h at 37 °C proceeded by thermocycling (5- 55 °C, 1200×). Teeth were then exposed to compressive load till fracture at a crosshead speed of 1 mm/min. One-way ANOVA followed by Tukey post-hoc test was implemented to compare between more than two groups in non-related samples. The significance level was established at α = 0.05 for both tests.Results: Intact teeth significantly recorded the highest fracture resistance values among all groups. A significant difference was recorded among all the tested groups, with the EF recording the highest values, followed by the VB group then the XF group and ChP that recorded the lowest data. Negative control premolars significantly recorded the lowest fracture.Conclusions: After thermocycling, endodontically treated maxillary premolars restored with pre-heated thermos-viscous composite did not exhibit an increase in fracture resistance. Notably, our findings indicate that short fiber-reinforced composite demonstrated significantly higher fracture resistance compared to other types of composites assessed in this study. This suggests the potential superiority of short fiber-reinforced composite in enhancing the overall structural integrity of endodontically treated teeth subjected to occlusal forces.

This study aimed to evaluate various shade selection protocols using corrective light for shade selection with different viewing backgrounds and to assess the shade matching the performance of students in King Abdulaziz University Faculty of Dentistry (KAUFD). One-Hundred participants were recruited from undergraduate levels with clinical experience. Six different techniques took place with each participant individually using either daylight or corrective light (Smile Lite), with or without

Objective. The aim of the present study was to evaluate the adaptation of newly introduced bioactive restorative materials to the cavity floor using cross-polarization optical coherence tomography (CP-OCT). Materials and Methods. Round class V cavities were prepared on the proximal surfaces of sixty non-carious human anterior teeth (0.5 mm depth × 4 mm diameter), which were divided into groups according to the restorative material (n = 15). In the VF group, Vertise flow composite (Kerr, Orange, CA, USA) was used, in the BF group, Beautifil II composite (Shofu, Koyoto, Japan) was used, and in the AB group, ACTIVA BioACTIVE composite (Pulpdent, Watertown, NY, USA) was used. Cavities were restored using the bulk filling technique and cured according to the manufacturers’ instructions. Then, the specimens were immersed in a contrasting agent, and image acquisitions were taken by CP-OCT to calculate the adaptation percentage by using an image analysis software. Results. B-scans showed a diffuse bright band of white pixels at the tooth-resin interface that was interpreted as a micro-gap present between the cavity floor and restorative material. The Kruskal-Wallis test showed a statistically significant difference between all tested groups with the AB group representing the least gap formation, followed by the BF group, and then the VF group, which demonstrated the highest gap formation. Conclusions. In class V cavities, better adaptation to the cavity floor can be obtained when using ACTIVA BioACTIVE more than Vertise flow and Beautifil II composites. In addition, CP-OCT is considered a non-destructive imaging tool that helps in evaluating the quality of the tooth-restoration interface when bioactive composites are used.

Objective: 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).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). 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.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.