Based on their substrate specificity, they have been classified as collagenases, gelatinases, stromelysins, and matrylisins. Collagenase-1can hydrolyze type I, II, III, VI, VIII, and X collagens and gelatin T he gelatinase group of MMPs has two prominent members: gelatinase-A, (MMP-2) and gelatinase-B (MMP-9). Stromelysins have broad specificity with the ability to degrade proteoglycans, basement membrane, laminin, and fibronectin, in addition to collagens. The activating proteinases are themselves activated when conditions demand. The second mechanism by which MMP activity is regulated is through modulation of its synthesis. Tissues also contain another group of inhibitors, called Tissue inhibitors of metalloproteinases (TIMP). In gingivitis, the matrix destruction is mostly due to the activity of matrix metalloproteinases produced by polymorphonuclear leukocytes. In periodontitis however, matrix metalloproteinases produced by polymorphonuclear leukocytes, macrophages, keratinocytes, and fibroblasts contribute to matrix degradation.
Keywords:- MATRIX METALLOPROTEINASES
- PERIODONTAL DISEASE