Physical properties of acrylic resin teeth submitted to toothbrushing and immersion in beverages

Abstract

Background: Brushing and consumption of dye beverages may alter the physical properties of artificial teeth. Objective: The objective of this study was to evaluate the effect of toothbrushing and immersion in beverages in roughness and color of two types of artificial teeth: Biotone (B) and Biotone interpenetrating polymer network (IPN). Materials and Methods: For each tooth, seven groups were formed (n = 10): Toothbrushing (T), toothbrushing + water (TW), toothbrushing + coke (TCk), toothbrushing + coffee (TCf), immersion in water (W), coke (Ck), coffee (Cf). Roughness and color stability evaluations were performed before treatment and after treatment. According to the group, 11,000 brushing cycles were performed and specimens were immersed in beverages for 12 days, both simulating a period of 1 year. Color variations were captured by a spectrophotometer and roughness was analyzed by a profilometer. Color data were analyzed using analysis of variance (ANOVA) and Least significant difference test whereas roughness data were analyzed using ANOVA and Bonferroni test, both with α =0.05. Results: For Biotone, clinical significant color changes according to National Bureau of Standards (NBS) units were observed for the Groups T, TW, W, and Ck, and the results of ΔE were statistically similar among them (P > 0.05). For Biotone IPN, clinical significant color changes were found for TCf (4.86 NBS units) and Cf (4.82), and the results of ΔE were also similar among them. Surface roughness Ra (μm), regardless of the teeth, was reduced for the groups submitted to toothbrushing whereas no significant differences were found among the Groups W, Ck, and Cf. Conclusions: Toothbrushing had no influence on the color stability but significantly reduced the roughness, irrespective of the type of tooth.