Introduction: Accessory Mental Foramen (AMF) is an additional Mental Foramen (MF) situated nearby the regular MF and usually placed posterior to the MF. It is a rare anatomical variation in human mandibles. The incidence of accessory mental foramen depends on age, sex, Race, ethnicity, population. Its position, number and distance from usual mental foramen and the surrounding bony landmarks are highly variable. The accessory branch of the mental nerve passes through it. AMF may be one of the factors implicated in regional anaesthesia failure.

Aims and Objectives: The aim of this study is to evaluate the incidence of the accessory mental foramen, which is occasionally traced additional to the main mental foramen in the population of Rajasthan State.  

Materials and Methods: The present study was conducted using 50 dried human mandibles of unknown age & sex for analysing the incidence and morphological details of accessory mental foramen.

Results: 4 out of 50 (8 %) mandibles had Accessory Mental Foramen (AMF). Three specimens had unilateral AMF and one specimen had bilateral AMF. Shape of all AMF was circular with smooth margin.

Conclusion: The anatomical knowledge about existence of accessory mental foramen may be helpful to dental surgeons to avoid injury to neurovascular bundle during surgical procedures involving mandibular region. The detection of AMFs may reduce the rates of postoperative pain and paraesthesia in surgical procedures.

Keywords: Accessory mental foramen, Incidence, Mandible, Mental foramen.

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Sakshi Mathur

Ph.D. Scholar, Department of Anatomy,

S.M.S. Medical College, Jaipur, India