In Vitro Evaluation of Bacterial Adhesion of Streptococcus mutans and Enterococcus faecalis on Sand-Blasted, Acid-Etched, and Anodized Titanium Dental Implants.

Although the surface modifications of the implant have been widely proposed to enhance the osseointegration, their impact on microbial adhesion is still not explored. The present in vitro study was done to compare the bacterial adhesion of S. mutans and Enterococcus faecalis on sand-blasted acid-etched and anodized titanium dental implants. Three commercially available implants, namely SLA (n = 3), SLActive (n = 3), and TiUnite (n = 3), were inoculated with the prepared broth suspension of S. mutans and E. faecalis, and were incubated at 37°C for 48 h. After incubation, the colonies were counted using direct microscopy and the results were recorded as colony forming units/mL (CFU/mL). Mean CFUs were compared between the three implants by ANOVA and pairwise comparison by Tukey's HSD post hoc test using SPSS Software. p value of < 0.05 was considered to be statistically significant. TiUnite implant showed the highest bacterial adherence for S. mutans (3.49 ± 0.53 × 102 CFU/mL) and E. faecalis (35.14 ± 1.54 × 102 CFU/mL) followed by SLA and SLActive. These data demonstrated statistically significant differences between the three types of implants (P < 0.05). Pairwise comparison showed that there was a statistically significant difference between SLA and TiUnite (P = 0.004) and SLActive and TiUnite (P = 0.001) in terms of S. mutans colony count. In terms of E. faecalis colony count, there was a statistically significant difference between SLA and SLActive (P = 0.000), SLA and TiUnite (P = 0.000) and SLActive and TiUnite (P = 0.000). Compared with sand-blasted and acid-etched dental implants, anodized dental implants showed higher adhesion of S. mutans and E. faecalis.