Effect of Wet and Dry Finishing and Polishing on Surface Roughness and Miarohardness of Bulkfill Resin Composites

Objective: The aim of this in vitro study was to evaluate surface roughness and microhardness of two bulkfill resin composites after wet and dry finishing.
Materials and methods: Two Types of resin composite materials SonicFill (Sonic-activated bulk-fill Nanohybrid resin composite) and X-tra fil (Bulk-fill micro- hybrid light-cured posterior resin composite) were used. Thirty samples were fabricated of each resin composite using a metal mold measuring (6mm x 4mm). Composites were applied to molds and placed between two transparent Mylar strips and pressed flat with a microscopic glass slide. A glass slab was placed on top of the upper Mylar strip and a constant pressure was applied. The samples were cured according to manufacturers’ instructions. The samples were divided into three groups (n=10). Group A: No finishing (control group), Group B: wet finishing under water coolant, and group C dry finishing. Surface roughness was evaluated using a stereomicroscope and microhardness was measured by Vicker’s hardness tester. Data were analyzed using one-way ANOVA (P<0.05).
Results: X-tra fil showed a statistically significant higher surface roughness mean values than Sonicfill in group A (control group) and group C (dry finishing) at p value ≤ 0.015 and ≤ 0.001* respectively, while with the wet technique there was no statistically significant difference in the surface roughness mean values between X-tra fil and Sonicfill at p value> 0.05. The control group showed the lowest microhardness mean values in both materials. Dry finishing showed the highest microhardness mean values among the groups (P<0.05).
Conclusion: Dry finishing and polishing increased the surface roughness and microhardness of X-tra fil (microhybrid) and (nanohybrid sonic activated) Sonicfill resin composites.