Oral fluid matrix metalloproteinase (MMP)-8 as a diagnostic tool in chronic periodontitis

Abstract

Oral fluid matrix metalloproteinase (MMP)-8 as a diagnostic tool in chronic periodontitis Patricia Hernández-Ríos,1 Marcela Hernández,2,3 Mauricio Garrido,1 Taina Tervahartiala,4 Jussi M Leppilahti,4 Heidi Kuula,4 Anna Maria Heikkinen,4 Päivi Mäntylä,4 Nilminie Rathnayake,5 Solomon Nwhator,6 Timo Sorsa4,5 1Department of Conservative Dentistry, 2Department of Pathology and Oral Medicine, 3Laboratory of Periodontal Biology, Department of Conservative Dentistry, Faculty of Dentistry, University of Chile, Santiago, Chile; 4Department of Oral and Maxillofacial Diseases, Institute of Dentistry, Helsinki University and Helsinki University Central Hospital, Helsinki, Finland; 5Division of Periodontology, Department of Dental Medicine, Karolinska Institutet, Stockholm, Sweden; 6Department of Preventive and Community Dentistry, Faculty of Dentistry, College of Health Sciences, Obafemi Awolowo University, Ife, Nigeria Abstract: Periodontal diseases that affect the marginal and apical periodontium result from the interaction between bacterial biofilm and the host response. Oral fluid biomarkers might aid clinical diagnosis. Matrix metalloproteinases (MMPs) are a family of 24 proteases that act in physiological and pathological conditions. They can degrade almost all extracellular matrix constituents and regulate inflammatory processes. They are mainly inhibited by tissue inhibitors of metalloproteinases. The aim of this study was to perform a current literature review with a special reference on the diagnostic and clinical utility of oral fluid MMPs, especially MMP-8, and their inhibitors in periodontal and oral diseases. MMP-8 is the main collagenolytic MMP detected in oral fluids, such as saliva, oral mouthrinse, gingival crevicular fluid, and peri-implant fluid. MMP-8, and potentially MMP-9, in oral fluids represent strong biomarker candidates associated especially with periodontal disease diagnosis, severity, progression, and follow-up. Additionally, they show diagnostic potential for systemic conditions, such as pregnancy, myocardial infarction, and smoking. A commercially available mouthrinse, active MMP-8 chair-side/point-of-care lateral flow immunoassay, shows enough sensitivity and specificity to detect clinical signs of periodontitis. The current literature supports that high MMP-8 levels reflect the loss of periodontal supporting tissues rather than inflammation, representing a potentially useful side-diagnostic point-of-care oral disease biomarker, especially in periodontal diseases. Keywords: gingival crevicular fluid, saliva, biomarkers