Evaluation of Microbial Leakage at Implant Abutment Interfact for Different Implant Systems: An In Vitro Study

Two-stage implant systems result in gaps and cavities between implant and abutment that can act as a trap for bacteria and thus possibly cause inflammatory reactions in the peri-implant soft tissues. These gaps between the components are inevitable, and their clinical significance has so far been mostly neglected by both manufacturers and clinicians. This study is thus intended to evaluate microbial leakage at implant abutment interface in different implant systems. Four different systems, the Nobel tri-channel, the Nobel conical, the Equinox, and the Straumann, were used for this study. One microliter of a fresh broth suspension of Streptococcus mutans was added to the implant fixture (implant body). The implant was immersed in fresh heart brain infusion and was incubated at 37° for 48 hours. After incubation, 10 μL of the broth was made as lawn culture on sterile agar and the colonies were counted and recorded as colony-forming units per milliliter. Statistical tests were carried out on SPSS software and tests included analysis of variance (ANOVA) and P value was derived using Tukey's honestly significant difference post hoc test. After incubation, results were analyzed by evaluating the microbial leakage from each sample and it was observed that Nobel tri-channel had the least amount of microbial leakage and Equinox had maximum microbial leakage. The difference among all implant systems was statistically significant P < 0.05. The study concluded that least micro-leakage was found in the Nobel tri-channel whereas maximum microbial leakage was present in Equinox and Straumann.