Background: The role of blood group substance and its subsequent role in forensic cases is based on the fact that once a blood group of an individual is established, it remains constant throughout his life. Eruption is defined as the movement of the tooth from its site of development in alveolar bone to the occlusal plane in the oral cavity. Mandibular third molars, or wisdom teeth, are the most frequently congenitally impacted teeth. Hence, assessed the correlation of ABO blood grouping and impacted third molars. Materials & Methods: Total 510 patients impacted third molar teeth were included in this study. Patients were broadly divided into maxillary third molar impacted patients and with mandibular third molar impaction. Examination of blood samples was done for the assessment of blood groups of the patients. The Rh - group was excluded from the study due to insignificant number. All the results were analysed using SPSS software. Paired‘t’- test was used to assess the level of significance. Results: Out of 250 patients, 62 had A positive blood group, 52 had B positive blood group, 66 had O positive and 70 had AB positive blood group. However, no significant results were obtained on comparing the distribution of different blood groups in maxillary third molar impacted patients (p-value>0.05). Out of 250 patients, 59 had A positive blood group, 56 had B positive blood group, 60 had O positive and 75 had AB positive blood group. However, no significant results were obtained on comparing the distribution of different blood groups in mandibular third molar impacted patients (p-value>0.05). On comparing between the maxillary arch and the mandibular arch, no statistically significant results were obtained in relation to distribution of various blood groups. Conclusion: No relation exists between the third molar impaction and ABO blood grouping system
Key words: Blood group, Impacted, Molar