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Objective: To evaluate the color stability, surface roughness, and microhardness of resin-based composites (RBCs) after accelerated artificial aging (AAA) or immersion in beverages consumed by children. Material and Methods: Seventy specimens were prepared from each RBC (Z350-Z350, SS-Spectra Smart, AF-Admira Fusion, and EA-Estelite Asteria). Initial color, ∆E00, surface roughness, ∆Ra, and microhardness, ∆KHN readings were done. Specimens were separated into five groups (n=14): AAA (300 hours) and immersion (30 minutes daily/30 days) in Coca-Cola (CC), Grape juice (GJ), Chocolate milk (CM), or distilled water (DW). After the final readings, color and microhardness data were analyzed using two-way ANOVA, Tukey, and surface roughness by Kruskal-Wallis and Dunn's test. Results: SS exhibited the most significant color change in AAA, which differed from CC and GJ; the minor change occurred after CM and DW, which were distinct from each other. AF did not show a difference between the treatments. All RBCs exhibited a decrease in microhardness, except for SS, after AAA and EA in CC and DW. There was no difference in the surface roughness after treatments, except for AAA, which presented a minor change for Z350 and AF, differing from the other treatments. Conclusion: The beverages didn’t alter the surface roughness but decreased the microhardness of the RBCs, except for CC, which increased the microhardness of EA.

The color stability and surface uniformity are very important properties for dental aesthetics. Objective: To evaluate the color stability and surface roughness of different composites after artificial accelerated aging (AAA). Methods: Samples were made using the silorane-based Filtek P90 (3M-ESPE), nanohybrid Tetric N-Ceram (Ivoclar Vivadent), and GC Kalore (GC Company). Ceramic D. Sign (Ivoclar Vivadent) and Ketac N100 (3M-ESPE) resin-modified glass ionomer cement (RMGIC) served as controls. The values for color stability and surface roughness were recorded before and after AAA for non-C-UV (300 hours). Color stability was assessed as the difference between the coordinates obtained from the L*a*b* system. The surface roughness was analyzed with a rugosimeter. The surface value of each sample was taken as the average of these measurements. The one-way ANOVA and Tukey’s post-test with α=5% was used. Results: The greatest change in color stability occurred for the RMGIC (ΔE=18.7) and the least for ceramics (ΔE=2.1). No significant difference was noted among the composites (p>0.05). The surface roughness before and after AAA differed significantly only for the RMGIC (pConclusion: The two latest generation resins (Filtek P90 and GC Kalore) showed good results in terms of color stability and surface roughness for use in aesthetic restorations.

Objectives To evaluate the microbial contamination of pacifiers by Mutans Streptococci(MS) and the efficacy of different methods for their disinfection.Methods Twenty-eight children were assigned to a 4-stage changeover system with a 1-week interval. In each stage, children received a new pacifier and the parents were instructed to maintain their normal habits for 1 week. After this time, the pacifiers were subjected to the following 4 disinfection methods: spraying with 0.12% chlorhexidine solution, Brushtox® or sterile tap water, and immersion in boiling tap water for 15 minutes. Microbiological culture for MS and Scanning Electron Microscopy (SEM) were performed. The results were analyzed statistically by Friedman’s non-parametric test (a=0.05).Results The 0.12% chlorhexidine spray was statistically similar to the boiling water (p>0.05) and more effective than the Brushtox®spray and control (p