Effect of Finishing /Polishing Techniques and Time on Surface Roughness of Silorane and Methacrylate Based Restorative Materials

Aim: The study evaluated the efficiency of various finishing and polishing systems and the effect of finishing and polishing time by using various procedures on surface roughness and hardness of silorane based (FiltekP90) and methacrylate based (Z100) restorative materials. Method: The surface roughness and surface hardness were measured using a profilometer and Vickers hardness tester respectively. Ten specimens of each composite resin were randomly subjected to one of the following finishing/polishing techniques: A- Diamond burs with soflex discs; B- Diamond burs with Astropol polishing brush; C – Tungsten Carbide burs with soflex discs; D- Tungsten Carbide burs with Astropol polishing brush. To assess the effect of time period, specimens were finished and polished immediately and another delayed by a week. Data were analyzed using repeated measures ANOVA and Tukey’s test at a significant level of p<0.05.Results: Filtek P90 showed least Ra values with lower surface hardness than Z100. Delayed finishing / polishing of materials was better than immediate polishing in both the tested materials. Among all the polishing system for silorane based composites (Filtek P90), Diamond bur- Astropol and Astrobursh combinations to be used. Whereas in methacrylate based composites (Z100) Tungsten carbide bur- Soflex disc used showed good surface finish. Conclusion: Clinical significance of surface roughness and hardness is related to: i. Aesthetic appearance of restoration (discoloration and wear) ii. Biological consequences regarding periodontal health (gingivitis) iii.Development of secondary caries due to increase