The zymographic evaluation of gelatinase (MMP-2 and-9) levels in acute and chronic periapical abscesses

Objective. This study investigated the presence and levels of matrix metalloproteinases (MMP)-2 and -9 in periapical abscesses. Study design. Eighteen samples of intracanal exudates containing pus were collected from teeth with clinically and radiographically verified primary or secondary acute and chronic apical abscesses. Pro-and active forms of MMP-2 and MMP-9 levels were analyzed by using substrate gel zymography followed by an image analysis system. Statistical analysis was performed using the Kruskall-Wallis and Mann-Whitney U tests with Bonferroni adjustment. Results. Both forms of MMP-9 were detected in all pus samples and demonstrated marked differences among the experimental groups (P < .05). Primary or secondary acute apical abscess samples demonstrated significantly higher MMP-9 levels compared with MMP-2 levels (P < .01). However, MMP-2 could not be detected in chronic apical abscesses. Conclusion. According to the results of this study, gelatinases might affect the pathogenesis of acute and chronic periapical abscesses. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;108:e121-e126)