Evaluation of Surface Roughness and Streptococcus mutans Adhesion to Bulk-Fill Resin Composites Polished with Different Systems

Abstract

Purpose: Bacterial adhesion represents the initial step in biofilm formation, dental caries and decay. This study aimed to evaluate and compare surface roughness and bacterial adhesion to bulk fill resin composites polished with different systems. Methods: Filtek Z350 XT (Incremental-fill resin composite), Filtek Bulk-fill Posterior (Bulk-fill resin composite), and Tetric N Ceram (Bulk-fill resin composite) were used as resin composites. The polishing systems used in this study were Sof-Lex multi-step, PoGo one step, and Mylar strip. Scanning electron microscope (SEM) was used to examine the surface roughness and adhesion of Streptococcus mutans ATCC 25175 standard strain to bulk-fill resin composites. Results: The type of restorative materials did not affect the surface roughness or bacterial adhesion (p > 0.05) but the polishing systems were significant (p < 0.05) influencing factors. Furthermore, Pearson correlation revealed a statistically significant (p < 0.001) association (R = 0.943) between surface roughness and bacterial adhesion to the tested surfaces. Conclusion: Regardless of the restorative material, Mylar polishing system revealed the smoothest surface and the lowest adhesion of S. mutans as compared to Pogo one step and Sof-Lex multi-step polishing systems.