Search

Abstract Bulk-fill composites were introduced in dentistry to accelerate clinical procedures while providing adequate outcomes. Concerns regarding the use of bigger composite increments rely on the polymerization shrinkage and shrinkage stress, which may generate gaps on the adhesive interface and result in a reduced success rate. Objective: To evaluate the polymerization shrinkage stress of different bulk-fill resin composites and their elastic modulus. Materials and Methods: Fourteen specimens were made for each of the nine different resin composites (seven with 12 mm3 and seven with 24 mm3): Surefill SDR flow (SDR), X-tra Base (XB), Filtek Bulk Fill Flowable (FBF), Filtek Z350XT Flow (Z3F); Tetric Evo Ceram Bulk Fill (TBF), X-tra Fil (XF), Filtek Bulk Fill (FBP), Admira Xtra Fusion (ADM) and Filtek Z350 XT (Z3XT). Linear shrinkage stress was evaluated for 300 s with the aid of a linear shrinkage device adapted to a Universal Testing Machine. For each composite group, seven additional specimens (2x2x25 mm) were made and Young's modulus was evaluated with a 3-point bending device adapted in a Universal Testing Machine with 0.5 mm/min crosshead speed and 50 KgF loading cell. Results: For 12 mm3 specimens, three-way ANOVA showed that only SDR and TBF generated lower stress after 20 s. Considering 300 s, TBF, SDR, and XF generated the lowest stress, followed by ADM, FBP, XB, and FBF, which were similar to Z3XT. Z3F generated the highest stress values for all time points. Considering 24 mm3 specimens after 20 s, all bulk fill composites generated lower stress than Z3XT, except XB. After 300 s, SDR, FBP, and ADM generated the lowest stress, followed by TBF and XF. For elastic modulus, one-way ANOVA showed that FBF, SDR, Z3F, and ADM presented the lowest values, followed by XB and TBF. FBP, Z3XT, and XF presented the highest elastic modulus among the evaluated composites. Conclusions: Bulk-fill resin composites presented equal to lower shrinkage stress generation when compared to conventional composites, especially when bigger increments were evaluated. Bulk-fill composites showed a wide range of elastic modulus values, but usually similar to “regular” composites.

Tele-health is more than an innovative alternative; it is an excellent tool that enables access to health and education in health, making it possible to minimize distances, optimize time and reduce costs. Based on these advantages, some Brazilian Universities have used these actions in strategies of education, research and extension, aiming at the application of Tele-health in Brazil. In that way, the Bauru School of Dentistry - University of São Paulo (FOB-USP) has applied the use of information and communication technologies in health by means of a "Tele-Health League" (TL), in order to diagnose, prevent and treat diseases, in addition to educate the population and health services. Objective: The present study aims to introduce the characteristics of the Tele-Health League of FOB-USP, as well as the development of its projects. Material and Methods: The Tele-Health League consisted as a Diffusion Course approved by the Provost of Culture and Academic Extension of the University of São Paulo. It is composed as a large group enclosing professoriate coordinator, academician principal, contributing professors and league members, those, diversified between undergraduates students, graduated, health employees, technology and information areas. The participant members are evaluated by the presence frequency (minimum of 85%), and by the performance of tests and paperwork about the theoretical content provided. Results: In four years of activities, the TLFOB-USP obtained a high satisfaction index (90%), an increased number of vacancies due to the interest to become a member, more commitment of the professors of the University and the accomplishment of association with other Brazilian leagues. It is emphasized that the approval percentage of the course results in approval from approximately half of its members. Also, it is important to identify and repair the causes related to the quitting of some members. Conclusions: The results showed that the TLFOB-USP members, adjoining to the professor's participants, develop projects in Tele-helth, in Tele-aid and Tele-education areas, thus resulting in the involvement of the University and the community.

Abstract Extensive restorations in posterior teeth always bring doubts to the clinicians regarding the best protocol, mainly when structures of reinforcement were lost. Objective This study aimed to evaluate the effect of beveling on the fracture resistance and pattern of class II (MOD) restored teeth. Methodology Ninety human premolars were randomly assigned into 9 groups: CTR (control/sound); NC (cavity preparation, non-restored); RU (restored, unbeveled); RTB (restored, entire angle beveling); RPB (restored, partial/occlusal beveling); EC (endodontic access/EA, non-restored); EU (EA, unbeveled); ETB (EA, entire angle beveling); EPB (EA, partial/occlusal beveling). Teeth were restored with Esthet X resin composite and stored in distilled water for 24 h before the inclusion in PVC cylinders. The axial loading tests were performed with 500 kgF at 0.5 mm/min crosshead speed until fracture of the specimens. Fracture resistance and pattern were accessed and data were analyzed using one-way ANOVA and Tukey’s HSD test (α=0.05). Results Mean (±SD) failure loads ranged from 136.56 (11.62) to 174.04 (43.5) kgF in the groups tested without endodontic access. For endodontically accessed teeth, fracture resistance ranged from 95.54 (13.05) to 126.51 (19.88) kgF. Beveling of the cavosurface angle promoted the highest fracture resistance values (p