TIMP1 and periodontitis: Finally, among stage III grade C periodontitis patients, aMMP-8 levels were significantly positively correlated with HbA1c levels (Spearman's rho = 0.646,p = 0.044), as well as, with total MMP-8 (rho = 0.636,p = 0.048), PMN Elastase (rho = 0.729,p = 0.017), total MMP-9 (rho = 0.721,p = 0.019) and total MMP-8/TIMP-1 molar ratio (rho = 0.879,p < 0.001).