Çakmak, GülceDönmez, Mustafa BorgaAtalay, SevdaSilva de Paula, MarcellaFonseca, ManruqueSchimmel, MartinYılmaz, Burak2022-09-062022-09-062022Çakmak G, Donmez MB, Atalay S, de Paula MS, Fonseca M, Schimmel M, Yilmaz B. Surface roughness and stainability of CAD-CAM denture base materials after simulated brushing and coffee thermocycling. J Prosthet Dent. 2022 Aug 19:S0022-3913(22)00380-8. doi: 10.1016/j.prosdent.2022.06.006. Epub ahead of print. PMID: 35995602.0022-3913http://doi.org/10.1016/j.prosdent.2022.06.006https://hdl.handle.net/20.500.12713/3121Statement of problem: Denture bases machined from prepolymerized materials have become popular. However, information on the effect of simulated brushing and coffee thermocycling (CTC) on their surface roughness and stainability is lacking. Purpose: The purpose of this in vitro study was to compare the effect of simulated brushing and CTC on the surface roughness (Ra) and stainability of computer-aided design and computer-aided manufacturing (CAD-CAM) denture base materials and a heat-polymerized denture base material. Material and methods: Forty disk-shaped specimens were prepared from 3 CAD-CAM denture base resins (AvaDent, AV; Merz M-PM, M-PM; and Polident d.o.o, Poli) and a heat-polymerized polymethylmethacrylate resin (Promolux, CV) (n=10). Ra values of the specimens were measured by using a noncontact profilometer after conventional polishing. The color coordinates were also measured over a gray background with a spectrophotometer. Specimens were then consecutively subjected to simulated brushing for 20 000 cycles, CTC for 5000 cycles, and another 10 000 brushing cycles. Ra and color coordinates were measured after each interval. Color differences (?E00) were calculated by using the CIEDE2000 formula, and the data were analyzed by using 2-way analysis of variance and Tukey honestly significant difference tests (?=0.05). Results: The time interval had a significant effect on Ra (P<.001) as brushing cycles resulted in higher values than those at baseline and after CTC (P<.001). However, the differences between brushing cycles (P=.143) and between the baseline and after CTC (P=.994) were not significant. The interaction between the material type and time interval was significant for ?E00 (P=.016). The only significant difference in ?E00 values was observed between M-PM and CV after all treatments were completed (P=.029). Conclusions: Brushing increased the Ra of all materials when compared with the baseline. All materials showed similar stainability throughout the brushing and CTC processes. However, M-PM CAD-CAM denture base resin underwent a greater color change after all treatments were completed than conventional denture base resin. All color changes can be considered clinically small, considering reported perceptibility and acceptability thresholds.eninfo:eu-repo/semantics/closedAccessArticle228359956022-s2.0-8513629799110.1016/j.prosdent.2022.06.006Q1