ABSTRACT
OBJECTIVE: The aim of this study was to investigate the relationship between the immunohistochemical expression of MMP-1 and MMP-9 with the clinical behavior of central giant cell lesions (CGCLs) of the jaws. STUDY DESIGN: Paraffin-embedded tissue from 30 aggressive and 12 nonaggressive CGCLs was assessed for the expression of MMP-1 and MMP-9 using immunohistochemistry. RESULTS: Although cellular immunolocalization patterns of MMP-1 and MMP-9 were similar, mean values of expression estimation/SID scores of each protease were significantly higher in aggressive CGCLs in comparison with nonaggressive lesions. Moreover, linear regression analysis showed that there was a reasonably good correlation not only between the expression estimation but also among SID scores of the 2 proteolytic enzymes. CONCLUSION: The findings of this study suggest a role for MMP-1 and MMP-9 in the resorptive activity of different cellular groups in CGCLs and indicate that differences in immunoreactivity of these 2 proteolytic enzymes may underlie the distinct clinical behavior.