Detection of peri-implant inflammation by the use of a matrix metalloproteinase-8 chair-side test

BACKGROUND: Active matrix metalloproteinase-8 (MMP-8) enzymes are associated with inflammation and the deg- radation of implant-supporting tissues. A high concentration of these enzymes in the peri-implant sulcular fluid (PISF) has been associated with a pathological condition. The aim of the present study was to evaluate the ability of a chair-side MMP-8 test to individuate pathological peri-implant site. The working hypothesis is that positive response to MMP-8 test corresponds to pathological values of periodontal indexes. A secondary working hypothesis is that PISF sampling method influences the test accuracy. METHODS: Fifty implants from 50 patients were evaluated during scheduled follow-up appointments in a clinical setting using the MMP-8 chair-side test and periodontal indices (probing depth, bleeding on probing, plaque index and peri-implant inflammation index). Two methods of PISF sampling were tested. RESULTS: The MMP-8 test demonstrated significant diagnostic capacity and good sensitivity and accuracy regarding indices of bleeding on probing, plaque index, and peri-implant inflammation index but fair agreement. CONCLUSIONS: Further studies should be performed to better define the interpretation of the MMP-8 chair-test results and their correlation to peri-implant indexes.