Published: 2017-01-09

A study on the incidence of retromolar foramen in South Indian adult dried human mandibles and its clinical relevance

Suman Tiwari, Roopashree Ramakrishna, M. Sangeeta


Background: The retromolar foramen is one of the most important non-metrical anatomical variants in the mandible. The present study describes the incidence of retromolar foramen in South Indian adult dried mandibles and its clinical relevance.

Methods: One hundred South Indian adult dried mandibles of unknown sex were studied at the Department of Anatomy, MVJ Medical College, Bangalore for the presence of retromolar foramen. Its location, size, shape, distance of the foramen if present from the posterior border of socket for 3rd molar tooth, anterior border of ramus of the mandible were measured.  

Results: Retromolar foramen was present in 16 (16%) of the mandibles. Out of the 16 mandibles, it was present bilaterally in 3 (3%) mandibles and unilaterally in 13 (13%) mandibles (In 3 (3%) on the right side and in 10 (10%) on the left side). The mean diameter of the foramen was 1.33mm (range - 1.10-1.92 mm). It was oval in shape in 9 (9%) and rounded in shape in 7 (7%) mandibles. The mean distance of retromolar foramen from the posterior border of socket for 3rd molar tooth and anterior border of ramus were 6.15 mm (2.23-12.10) and 8.02 mm (3.24-13.12) respectively.  

Conclusions: The knowledge about the incidence of the retromolar foramen is important for dental surgeons during various anaesthetic, implantation and surgical procedures of the mandible, especially during extraction of the lower last molar tooth.  



Mandible, Ramus of mandible, Retromolar fossa, Retromolar foramen, Retromolar canal, Third molar tooth

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