Background: Infraorbital foramen is located in the maxilla and it conveys infraorbital vessels and nerves, the knowledge of its morphometry and variations is therefore mandatory to do therapeutic infraorbital nerve block or any surgical procedures. Aims & Objective:To study morphometry of infraorbital foramen and its laterality in dry adult skulls of north Karnataka population. Materials and Methods: In this study we examined 100 infraorbital foramina and measured its distance with bony features adjacent to it and the shape, presence of accessory foramina were observed . The infraorbital foramen was the landmark from which the distance between the following bony structures were examined; Nasion (NAS), Zygomaticomaxillary suture (ZMS), Anterior nasal spine (ANS), and the distance between the inferior orbital rim(IOR) to optic canal (OC), infraorbital foramen IOF), inferior and superior orbital fissure (IF & SF). The average mean and standard deviation were calculated for every measurement. Paired t– test was used to compare the parameters between sides and gender for each measurement. Results: The most common shape of infraorbital foramen found in the present study is oval (39%) followed by semilunar (27%). Roundshaped foramen was found in 22% of skulls, triangle shaped foramen was found in 12% and accessory foramina were present in 11% of the skulls. In the present study, we found triangle shaped foramen in 12% skulls and also the number of accessory foramina was found to be higher which emphasise the need to take ethnicity into account as triangle shaped foramen is unique in south Indian population as affirmed by previous authors. Conclusion: The results show significance with respect to gender and side which makes the knowledge of its morphometry obligatory for surgical procedures.

Keywords: Infraorbital Foramen; Infraorbital Nerve Block; South north karnataka Population; Accessory Foramina.