Abstract
Dental caries and gingivitis are highly prevalent worldwide, with limited evidence on the role of ABO blood groups in influencing susceptibility among Indians. A cross-sectional study was conducted on 600 adults, with blood groups determined serologically; caries assessed using the DMFT index and gingivitis using the Gingival Index. Blood group O showed the highest mean DMFT (4.82 ± 2.15) and gingivitis prevalence (82.6%), with significant differences across groups (p<0.01). Logistic regression identified group O as an independent predictor for high caries (OR=2.15) and gingivitis (OR=1.94). Blood group O may represent a non-modifiable risk factor for poor oral health, highlighting the need for targeted preventive strategies.