Effect of finishing procedures on the surface of resin composites

Objectives: This study assessed the influence of 6 finishing procedures on the surface roughness of 7 resin composites (Extra-Low Shrinkage (ELS) Saremco, Micro-Hybrid Composite (MCH) Saremco, Gradia Direct Anterior (GDA) GC Corporation, Ceram'X Duo (CXD) Dentsply, Beautifil I (BI) Shofu, Metafil CX (MCX) Morita, Grandio (GR) Voco) after using a silicon-carbide-impregnated polishing brush (Occlubrush, Kerr-Hawe). Methods: Samples of materials were light-cured (Optilux Demetron 501 at 800mW/cm2) under a mylar strip and finished using 6 procedures using burs from Edenta Company: FP1: 40µm diamond bur, FP2: 40µm+20µm diamond burs, FP3: 40µm+20µm+15µm diamond burs, FP4: 8 fluted tungsten carbide bur, FP5: 8+16 fluted tungsten carbide burs, FP6: 8+16+30 fluted tungsten carbide burs. Finishing and polishing steps (polishing brush operating at 5000rpm using dry conditions) were carried out immediately after the end of the light curing. Surface roughness of the samples was measured using a Mitutoyo Surftest SV400 model. Results: Ra values (µm) expressed as mean values (standard deviation) are given in the following table. Kruskall-Wallis statistical tests (n=5) were used in order to compare the influence of the finishing procedures on the resin composites. For each line, groups with the same letter (a,b,c,d) are not statistically different. For each column, groups with the same letter (A,B,C,D,E) are not statistically different. Conclusion: Finishing procedure and the structure of the resin composite influence the roughness surface parameter (Ra) when using a silicon-carbide polishing brush.