Comparative Evaluation of Effect of Mechanical, Chemical, and Mechanico-chemical Cleaning on Surface Roughness of Commercially Available Silicone Soft Relining Materials

A BSTRACT Introduction: The mechanico-chemical mode of denture cleaning is an efficient method with a combination of favorable properties of both the methods of cleaning. Aim: To evaluate and compare the effect of mechanical, chemical, and mechanico-chemical cleaning on surface roughness of two commercially available silicone soft relining materials. Materials and Methods: The present study was an in vitro , descriptive, institutional study conducted over a period of 8 months. The total sample size needed with 80% G* of the study was found to be forty. Forty polymethyl methacrylate blocks of dimension 2 mm × 10 mm × 20 mm were fabricated and relined with either heat-polymerized or autopolymerized silicone soft relining materials. The specimens were categorized into eight distinct groups and were further subjected to no cleaning, mechanical cleaning, chemical cleaning, and mechanico-chemical cleaning. Test specimens were assessed at baseline and postintervention using the inbuilt profilometer of Multi-Functional Tribotester. The data obtained were subjected to statistical analysis. Statistical significance was set at P < 0.05. Results: A statistically significant difference between intragroup and intergroup surface roughness values at baseline and postintervention (cleaning method) for the above-mentioned silicone relining materials ( P < 0.001) was observed. Maximum surface roughness values were exhibited by mechanico-chemical cleaning method. Conclusion: Heat-polymerized silicone relining materials exhibited less change in surface roughness values compared to autopolymerized silicone relining materials in all methods of cleaning. Mechanico-chemical cleaning method imparted maximum surface roughness for both the materials. However, it was lower than clinically acceptable value of 2.2 μm, which did not favor bacterial colonization.