Comparative evaluation of effectiveness of chemical, mechanical and chemico-mechanical methods of denture cleaning for removal of stains from heat polymerised acrylic resin denture base - An in- vitro study

Abstract

An essential quality of acrylic resin denture bases is colour stability. Over time, acrylic resin bases have a tendency to attract stains, which causes the denture base's colour to alter. These modifications sometimes make the denture less aesthetically pleasing for the wearer, which leads to patient unhappiness and higher replacement costs. The study's objective was to evaluate and compare the effectiveness of cleaning dentures using chemical, mechanical, and chemico-mechanical methods for removing stains from the heat polymerized acrylic resin denture base.A total of 120 samples of heat polymerised acrylic resin were fabricated and stained using sambhar solution for 10 days under controlled conditions. The baseline optical density of the samples was determined. The samples were then subjected to stain removal procedure by either - chemical, mechanical or chemico-mechanical method. After which the optical density was again determined. The efficiency of the three methods used was determined by the difference in the optical density after staining and post cleaning and compared with the baseline optical density measured previously. The data was analysed using One-way ANOVA test. Post hoc comparison was made by Bonferroni t-test. p<0.0.5 was considered as statistically significant. Data analysis was done using the statistical software STATA version 13.0.The results suggested that the chemico-mechanical method was the best method for stain removal from the acrylic samples. However, the mechanical method of denture cleaning was found to be equally effective. The chemical method was least effective in removing stains from the surface of heat polymerised acrylic resin. The chemico-mechanical method was 95.16% effective and the mechanical method used was 92.12% effective, proving that the chemico-mechanical was the most effective method for removing stains from the acrylic resin amongst the 3 techniques compared.