Effects of cyclosporin A on alveolar bone: An experimental study in the rat

Background: There have been several investigations on the role of cyclospor in A (CSA) in gingival hyperplasia in both animals and humans, However, les s attention has been given to the drug's effect on alveolar bone. This stud y used light microscopy to histologically and histometrically evaluate the effects of CSA on alveolar bone in the rat. Methods: Sixty, 6-week-old Sprague-Dawley rats were separated into test and control groups, Animals in the test group received CSA in mineral oil (30 mg/kg body weight) daily by gastric feeding over the 6-week study, Control animals received only mineral oil. Ten animals from each group were sacrifi ced at weeks 2, 4, and 6. After histologic processing, the labial crest of the alveolar bone in the anterior mandible was evaluated by light microscop y. Results: A distinct pattern of increased osteoclasia and reduced bone forma tion was observed in the CSA-exposed animals compared to the controls. Incr eased osteoclasia was observed in periodontal sites and decreased bone form ation was observed in symphyseal sites. Conclusions: The results suggest that CSA has distinct effects on alveolar bone.