MMP8 and Peri-Implantitis: IL-1β +3954 C/T, ET-1 and IL-1β, MMP-8 rs11225395 (T allele), MMP8 (−799 C/T), and CD14 rs2569190 showed consistent associations with increased peri-implantitis risk, while the results for TNF-α −308 G/A were inconsistent across populations.