RESUMO
OBJECTIVE: The aim of this study was to evaluate the effects of alcohol and nicotine, when used alone or simultaneously, on the alveolar bone loss area resulting from ligature-induced periodontitis in rats. STUDY DESIGN: Forty adult male rats received a cotton ligature in the first lower molar sulcular area, and the animals were randomly assigned to different treatments (n = 10, each group) including daily peritoneal injections of saline solution (group A), submitted to self-administration of alcohol 25% (group B), nicotine solution in concentration 0.19 µl/ml (group C), and nicotine solution in concentration 0.19 µl/ml plus self-administration of alcohol 25% (group D). Five weeks later, the animals were sacrificed, and the samples were routinely processed for semi-serial decalcified sections. RESULTS: Ligated teeth showed more alveolar bone loss than unligated ones (p < 0.05). Unligated teeth showed no significant differences between each other (p > 0.05). Analyses between the ligated teeth showed that the group C (nicotine) or group B (alcohol 25%) each had increasing alveolar bone loss in the furcation area, and the simultaneous combination alcohol and nicotine (group D) intensified these effects (p < 0.05). CONCLUSION: The results suggest that the simultaneous combination of alcohol and nicotine have a synergistic effect in the progression of periodontitis, evidenced by increased furcation region bone destruction in periodontal disease in rats. Key words:Alveolar bone loss, periodontitis, nicotine, alcohol, rats.