The Effect of Polishing on Surface Roughness of Tissue Conditioners

Purpose: Surface roughness can affect microbial colonization of long-term denture liners, alloys, and denture acrylic. The purpose of the present study was to examine the effect of finishing and polishing procedures on surface roughness of 4 temporary resilient denture liners (tissue conditioners). Materials and Methods: Mean surface roughness was measured for 4 materials (Lynal, Visco-gel, Coe-Soft, and Functional Impression Tissue Toner [FITT]) finished in 4 ways: unfinished (control); polished; reduced, unpolished; and reduced, polished. Samples were allowed to polymerize at 37°C for 24 hours, and the surface roughness was measured using a Mitutoyo Surftest 212. Results: Mean surface roughness ranged from 1.8 ± 0.8 µm for polished Lynal to 7.8 ± 1.1 µm for reduced, unpolished FITT. All polished samples were smoother than unpolished samples (including controls), whether or not the samples were reduced with a bur. Conclusion: Polished samples of tissue conditioning material had lower mean surface roughness measurements than control or reduced, unpolished samples at the 95% level of confidence. There was no difference in mean surface roughness measurements of control samples and unpolished samples reduced with a bur at the 95% level of confidence. Mean surface roughness differed significantly between the materials tested.