Effect of surface sealant agents on the surface roughness and color stability of denture base materials

Statement of problem. The effects of surface sealant agents on the surface roughness and color stability of denture base materials are unknown. Purpose. The purpose of this in vitro study was to evaluate the effects of different polishing methods on the surface roughness and color stability of denture base materials. Material and methods. A total of 120 specimens were fabricated from 2 poly(methyl methacrylate) (PMMA) and 1 polyamide denture base materials and divided into 4 groups (n=10 in each group) according to the applied surface treatment procedure: conventional polishing (control) and 3 surface sealant coupling methods. Surface roughness average (R-a) values were measured using a profilometer. Color parameters were measured using a spectrophotometer before and after being stained with coffee. Color differences (CIEDE 2000 [Delta E-00]) were calculated. Data were statistically analyzed using 2-way ANOVA and Tukey honest significant difference test (alpha=.05). Results. No statistically significant difference were found between surface roughness values of the control and those of the specimens treated using a surface sealant agent (P>.05). The highest color difference was calculated for the polyamide control group. Statistically significant differences were found between the control group and the group treated with the polyamide surface sealant agent (P<.05). Conclusions. All specimens had a surface roughness value higher than the plaque accumulation threshold (0.20 mu m). The color changes observed were clinically unacceptable, except for conventionally polished and one type of surface sealant applied microwave polymerized PMMA denture base material.