Comparative evaluation of the depth of cure and surface roughness of bulk-fill composites: An in vitro study

Background. Composites are in great demand due to the esthetic needs of the patients, which explains a wide variation in the types of available composites. However, the mechanical strength of the materials is questionable. Therefore, the mechanical properties of the newly available bulk-fill composites have been tested. Objective. The main objective of the study was to compare the depth of cure (DOC) and surface roughness of 3 different bulk-fill composites: X-tra fil (R) (XTF), Tetric EvoCeram (R) Bulk Fill (TEC) and Beautifil (R) Bulk Restorative (BBR). Material and methods. Fifty-seven (n =19 in each group) samples were made using brass molds. All samples were subjected to Vickers hardness testing and profilometry. The one-way analysis of variance (ANOVA) test was used for the data analysis, followed by Tukey's post hoc test. Results. The differences in the mean surface microhardness values of the materials were statistically significant (p < 0.001), with XTF showing the highest value. The TEC composite showed a higher surface roughness as compared to BBR and XTF. Conclusion. The results of the present study indicate that variations in the filler size and amount significantly influence the DOC and surface roughness of dental composites. Among the tested composites, the multi-hybrid composite exhibited superior DOC (XTF), whereas the nanohybrid composite exhibited superior surface finish (TEC).