Reducing the surface roughness of dental acrylic resins by using an eggshell abrasive material

Abstract

Statement of problem: Excessive surface roughness of denture base resins adversely impacts oral health.

Purpose: The purpose of this in vitro study was to examine the abrasive potential of eggshell powder in reducing the surface roughness of denture base resins.

Material and methods: Thirty poly(methyl methacrylate) specimens were fabricated and polished with eggshell powders of different particle sizes and with pumice. The average surface roughness (R_a) after polishing was measured with a profilometer. Scanning electron microscope and optical electron microscope techniques were used to assess the surface roughness morphology of the specimens. ANOVA was used to analyze the R_a values. The Tukey honest significant differences and Bonferroni tests were used to identify differences between the 2 abrasive materials (α=.05).

Results: Significant differences in the R_a values were observed between the fine and medium eggshell powder abrasives (P<.05). Similarly, significant differences were found between pumice and the fine eggshell powder abrasives (P<.001). No significant differences were found between pumice and the medium eggshell powder abrasive (P>.05). Specimens polished with pumice had the highest R_a values, whereas specimens polished with the fine eggshell powder abrasive had the lowest R_a values.

Conclusions: By connecting the R_a values to the threshold limit value of 0.2 μm, eggshell powder abrasive finished denture acrylic resin surfaces better than pumice.