Matrix metalloprotease（MMP）-13 is one of the most important proteinases in vivo. It belongs to the collagenases of the MMP hyperfamily. Its main function is to decompose extracellularmatrix, participating in many physiological and pathological processes. Many kinds of cells can express matrix metalloprotease and its expression is adjusted by many factors, such as cell growth factor, hormone, tissue inhibitor of metalloproteas, and so on. Its main operational project is Ⅰ-Ⅲ collagen. And it has key contact with adult chronic periodontitis.
