Effect of different polishing techniques on surface properties and bacterial adhesion on resin-ceramic CAD/CAM materials.

Objectives: The aim of this study is to evaluate the adhesion of Streptococcus mutans on the surface of CAD/CAM materials with various surface treatments.

Methods: Vita Enamic, Lava Ultimate, and Cerasmart materials were used in this study. A total of 90 samples were prepared (n = 10). After various finishing and polishing procedures (non-polished, manual polished, and glazed), surface roughness (SR) measurements, surface free energy (SFE), and elemental and topographic analysis with FIB-SEM/EDX were used to evaluate the samples' surface properties. To improve bacterial adhesion, CAD/CAM materials were covered with sterile artificial saliva containing mucin for pellicle formation and incubated for 1 h at 37 °C. Bacteria were then inoculated into the pellicle-coated specimens, and incubation was performed at 37 °C for 24 h. Bacterial adhesion was determined as × 10 CFU/mL and monitored using FIB-SEM analysis. The Kolmogorov-Smirnov test was used to statistically analyze the normality of the distribution; the groups were then compared using one-way ANOVA and Tukey's test.

Results: The SR of the control group was statistically higher in all materials (p < 0.05). There were no statistically significant differences in SR between all materials in the non-polished and manual polished groups (p > 0.05). The Vita Enamic control group exhibited the highest SFE value. The highest S. mutans adhesion was observed in non-polished (p < 0.05). Vita Enamic samples had higher CFU than other groups.

Conclusions: Non-polished surfaces showed higher SR and bacterial adhesion. Polishing processes affected the surface properties and bacterial adhesion.

Clinical Relevance: Care must be taken in polishing restorations to minimize the risk of bacterial adhesion and recurrent caries.

Trial Registration: In this study, the materials used for dental treatments are in vitro evaluated. Due to that, this study is not registered to clinical trials.