Research Article Morphometric Analysis of the Infraorbital Foramen: The Clinical Relevance Deepthi Nanayakkara, 1 Roshan Peiris, 1 Navini Mannapperuma, 1 and Amal Vadysinghe 2 1 Division of Anatomy, Department of Basic Sciences, Faculty of Dental Sciences, University of Peradeniya, 20400 Peradeniya, Sri Lanka 2 Department of Forensic Medicine, Faculty of Medicine, University of Peradeniya, 20400 Peradeniya, Sri Lanka Correspondence should be addressed to Deepthi Nanayakkara; deepthinanayakkara@yahoo.com Received 25 September 2016; Revised 11 November 2016; Accepted 7 December 2016 Academic Editor: Iwao Sato Copyright © 2016 Deepthi Nanayakkara et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te present study was conducted to ascertain the shape, size, presence of accessory foramina, direction, and the precise position of the infraorbital foramen (IOF) in relation to the inferior orbital margin (IOM), anterior nasal spine (ANS), nasion (Na), maxillary teeth, and supraorbital foramen/notch (SOF/N) in adult skulls in a Sri Lankan population. Fify-four skulls (42 males and 12 females) were analyzed. Te IOF was oval in shape (38.6% and 36.3% on the right and lef side, resp.) in a majority of skulls. Te direction of the IOF was mostly medially downward (48.6%). Accessory foramina were found in 7.4% of the skulls. Te infraorbital foramina were located at a mean distance of 6.52 ± 2.03 mm and 7.30 ± 1.57 mm, vertically below the IOM on the right and lef side, respectively; 33.81 ± 2.68 mm and 34.23 ± 2.56 mm from the ANS on the right and lef side, respectively; and 42.37 ± 3.52 mm and 42.52 ± 3.28 mm from the Na on the right and lef side, respectively. In relation to the upper teeth the majority of IOF (37.5% and 55.9% on the right and lef side, resp.) were located in the same vertical axis as the tip of the buccal cusp of the maxillary second premolar tooth. 1. Introduction Te infraorbital foramen (IOF) is located on the maxillary bone about 1 cm inferior to the infraorbital margin [1]. Te infraorbital nerve and vessels are transmitted through this foramen. Te infraorbital nerve, the continuation of the maxillary or second division of the trigeminal nerve, is solely a sensory nerve. It traverses the inferior orbital fssure into the inferior orbital canal and emerges onto the face at the IOF. It divides into several branches that innervate the skin and the mucous membrane of the midface, such as the lower eyelid, cheek, lateral aspect of the nose, upper lip, and the labial gum [1]. Te IOF is an important landmark in facilitating anaes- thetic and surgical interventions of the midface region. Te infraorbital nerve block is widely used to accomplish regional anaesthesia during surgeries involving the midface region and paranasal sinuses [2, 3]. Traumatic or iatrogenic injury to the infraorbital neurovascular bundle may result in bleeding and hypoesthesia or paraesthesia or anaesthesia in the region of its supply [4]. Hence, detailed knowledge of the precise anatomical location and the possible variations of the IOF is fundamental to ensure safe and successful regional anaesthesia and to avoid the risk of damaging the neurovascular bundle during surgery in this region. Multiple studies have demonstrated that the dimensions and relative position of the IOF vary between the genders and among diferent population groups [5–22]. To ascertain its precise location various sof tissue and bony landmarks have been utilized. Signifcant variations have been reported in the literature with regard to the position of IOF in relation to the infraorbital margin [3, 5, 6, 8, 14]. Moreover, the position of IOF in relation to maxillary teeth has been shown to vary among population groups [3, 13, 21]. Despite its clinical relevance, information available on the dimensions and relative position of the IOF in the Sri Lankan population is scarce. Hence, the present study was under- taken to ascertain the shape, presence of accessory foramina, direction, and the dimensions of the IOF and its position in relation to clinically relevant anatomical landmarks. Hindawi Publishing Corporation Anatomy Research International Volume 2016, Article ID 7917343, 8 pages http://dx.doi.org/10.1155/2016/7917343