N-Acetylcysteine, a Thiol Antioxidant, Decreases Alveolar Bone Loss in Experimental Periodontitis in Rats

Abstract

Background: The purpose of this study was to analyze the morphometric and histopathologic changes associated with experimental periodontitis in rats in response to systemic administration of N-acetylcysteine (NAC). Methods: Forty-three Wistar rats were divided into five experimental groups: non-ligated (NL) group (n = 10), ligature only (LO) group (n = 10), and groups that were administered NAC systemically (7, 35, or 70 mg/kg body weight per day [NAC7, NAC35, and NAC70 groups, respectively]; n = 8, 9, and 6). Silk ligatures were placed at the gingival margin of the lower first molars in a mandibular quadrant. The study duration was 11 days, and the animals were sacrificed at the end of this period. Changes in alveolar bone levels were measured clinically and tissues were histopathologically examined to assess the differences among the study groups. Results: At the end of 11 days, the alveolar bone loss was significantly higher in the LO group compared to NL, NAC7, NAC35, and NAC70 groups (P<0.05). There was no statistically significant difference in the osteoclast numbers among the study groups (P>0.05), whereas the effect of NAC was dose-dependent. Conclusion: NAC prevented alveolar bone loss in the rat model, in a dose-dependent manner, when administered systemically. J Periodontol 2009;80:672-678.