Anatomical Variations & Surgical Relevance of Infraorbital Foramen in Human Dry Adult Skulls Among South Indian Population

Background: The infraorbital nerve and arteries are transmitted via the infraorbital foramen, which is situated on the maxillary bone under the orbit. The infraorbital nerve is therapeutically important in periorbital, dental, and maxillofacial treatments because it supplies sensory innervation to the nasal vestibule, upper lip, and lower eyelid. Variations in its location and the presence of accessory foramina may lead to ineffective anesthesia or nerve injury. Hence, precise anatomical knowledge is essential. The objective is to study variations in the location of the infraorbital foramen, determine the incidence of accessory foramina, and measure distances between the infraorbital foramen and key anatomical landmarks such as the infraorbital margin and piriform aperture. Material and Methods: This observational study included 40 dry adult human skulls obtained from PSG Institute of Medical Sciences and Research, Coimbatore. Intact skulls without deformities were included. Measurements were taken bilaterally using a digital vernier caliper (accuracy 0.01 mm). The presence of accessory foramina was noted macroscopically. Data were analyzed using SPSS software. Results: The mean distance between the infraorbital foramen and infraorbital margin was 6.33 ± 1.36 mm on the right and 6.73 ± 1.37 mm on the left. The mean distance between the infraorbital foramen and piriform aperture was 15.23 ± 1.97 mm on the right and 14.49 ± 1.93 mm on the left. Accessory foramina were observed more frequently on the left side. The findings were consistent with previous Indian studies, indicating population-based variation. Conclusion: The location of the infraorbital foramen shows variation influenced by ethnicity. Accessory foramina are clinically significant and more common on the left side. Knowledge of these variations is essential for accurate nerve blocks and to prevent neurovascular injury during surgical procedures.

Keywords: Infraorbital foramen, Accessory infraorbital foramen, Morphometry, Anatomical variation, Infraorbital margin, Piriform aperture, Maxillofacial surgery.