摘要：The purpose of this study was to evaluate, the interrelationship between serum total antioxidant capacity, C-reactive proteins, cotinine levels and periodontal diseases in smokers and non smokers. A total of 67 male patients were examined, 33 (49.2%) were smokers and 34 (50.7%) were non smokers. The amount of visible plaque score, gingival bleeding Index and community periodontal index were recorded. The patients in each group were divided into those with gingivitis and those with periodontitis. The serum cotinine level was analyzed by ELISA technique. The antioxidant capacity was measured by using the ferric reducing ability of plasma assay. C-reactive protein levels were measured by using Beckman Coulter Image Immunochemistry System. Serum cotinine level showed a highly significant increase (p = 0.001) and antioxidant level showed a highly significant decrease (p = 0.001) in the smoker group when compared to the non-smoker group. In gingivitis group, highly significant difference of serum cotinine (p = 0.001) and antioxidant (p=0.001) levels was found between the smokers and non smokers. The periodontitis group showed high significant difference for the cotinine level (p = 0.001) but less significant difference for antioxidant level (p = 0.046). Mean plaque score and bleeding on probing score were found higher in smokers; however these scores were not statistically significant (p > 0.05). In smoker participants, a significant difference of C-reactive protein level was found between gingivitis and periodontitis groups. Smoking effect was more pronounced in patients with periodontitis compare to gingivitis. Several changes seem to be effected not only by smoking but also by severity of inflammation and destruction in periodontitis. Periodontitis group showed highly significant difference for the cotinine level, but less significant for antioxidant level compared to gingivitis groups including only smokers participents. Also In smoker participants, a significant difference of C-reactive protein level was found between gingivitis and periodontitis groups.
