Cutaneous distribution of infraorbital nerve

The aim of this study is to elucidate precisely the cutaneous distribution of the infraorbital nerve. Ten hemifaces of five Korean adult cadavers (2 males and 3 females) were subjected to the dissection. The cutaneous branches of the infraorbital nerve were distributed over the infraorbital area, which bounds on superiorly the lower eyelid margin, inferiorly the horizontal line crossing the mouth corners, medially 0.5 cm to midline, and laterally 2 cm lateral to the temporal canthus of the eyes. The infraorbital nerve had 19.5 branches (range, 15-24 branches). The mean area supplied by the infraorbital nerve was 25.8 cm2 (range, 24.0-28.2 cm2). The mean area of the superior labial branch was 13.1 cm2 (range, 11.2-14.3 cm2) and broader than either the 7.5 cm2 (range, 6.6-8.8 cm2) of the lower palpebral branch or the 7.6 cm2 (range, 6.7-9.3 cm2) of the external nasal branch. The external nasal branch was overlapped with the lower palpebral and superior labial branch, but the last two branches do not overlap each other. The nonoverlapped branch of the infraorbital nerve exhibits a restricted anesthesia, but the overlapped branch sustains sensory perception to some extent when being damaged.