The relationship between matrix metalloproteinases-8 and peri-implantitis: A systematic review and meta-analysis

BACKGROUND: Peri-implantitis diagnosis typically involves evaluating inflammation, pocket depth, bleeding, and bone loss around dental implants. Although these methods are reliable and convenient, they mainly determine the history of the disease instead of the current activity or disease susceptibility. This meta-analysis evaluates whether the matrix metalloproteinase (MMP)-8 level in the peri-implant crevicular fluids (PICF) can be associated with peri-implantitis. METHODS: The research was conducted in February 2022, where three electronic databases were searched and complemented with a manual search. The search criteria included original cross-sectional and longitudinal studies that compared MMP-8 biomarkers in crevicular fluids around healthy implants with unhealthy implants (peri-implantitis). To assess the risk of bias, the Newcastle-Ottawa Quality Scale was used. The data was analyzed using the RevMan program, and the standardized mean difference (SMD) with a 95% confidence interval was applied to evaluate the MMP-8 levels, with a significance level of p less than 0.05. RESULTS: Out of 1978 studies, six were eligible. This meta-analysis included 276 patients divided into two groups; 121 patients (124 implants) in the peri-implantitis group and 155 patients (156 implants) in the health implants group. The quality of the included studies was evaluated as high to moderate. The meta-analysis showed a significant increase in MMP-8 levels in individuals with peri-implantitis compared to those with healthy implants (SMD = 1.43, 95% CI [0.19, 2.68], p = 0.02). CONCLUSION: The current meta-analysis found that the levels of MMP-8 in PICF were significantly elevated in peri-implantitis cases compared to healthy controls, indicating a potential link between MMP-8 and peri-implantitis. However, the meta-analysis does not provide evidence for MMP-8 as a diagnostic test for peri-implantitis. Further research, specifically diagnostic accuracy studies, is needed to establish the value of MMP-8 as a diagnostic tool for peri-implantitis.