RESUMO
Background: The presence or absence of blood group antigens has been associated with various diseases, with antigens also acting as receptors for infectious agents. Scanty literature is available in assessing the relative liability of blood group phenotypes to periodontal diseases. This research was conducted to determine the association of the ABO blood group and Rhesus (Rh) factor to periodontal diseases to assess whether they could be the predictors of periodontal diseases. Materials and Methods: A total of 1,220 subjects aged between 20 and 55 years were selected on a random basis. The study populations were segregated into three groups according to Ramfjord's periodontal disease index: Healthy, Gingivitis and Periodontitis. Blood samples were collected to identify the ABO blood groups and the Rh factor by the slide method. Results: Blood group A showed a significantly higher percentage in the gingivitis group and blood group O showed a higher percentage in the periodontitis group. The blood group AB showed the least percentage of periodontal diseases. The distribution of Rh factor in all groups showed a significantly higher distribution of Rh-positive. Conclusion: The genetic factors may alter the oral ecology and the process of periodontal disease. These data are suggestive of a broad correlation between periodontal diseases and blood groups, which may act as risk predictors for periodontal diseases. This will make it possible to better-understand the risk factors of diseases of the periodontal tissues and to predict the effective methods of prevention and treatment of periodontal diseases.