Morphometric study on the infraorbital foramen in relation to sex and side of the cranium in northeastern Brazil.

Detailed knowledge of the possible anatomical and morphometric variations of the infraorbital foramen (IOF) is important for ensuring safe and successful regional anesthesia, and for avoiding iatrogenic nerve injuries during surgery on the middle third of the face. To conduct a morphometric study on the IOF, correlating this with sex and side of the cranium. Two hundred forty-two crania were used (148 male and 94 female). Measurements were made with the aid of digital calipers with precision to 0.01 mm. Presence of foramina and their multiplicity was also observed. The data were analyzed descriptively and analytically. Statistical significance was stipulated as 5% (P≤0.05). The IOF was found bilaterally in all the crania, and 26 of them presented multiplicity. The distance from the IOF to the anterior nasal spine was greater in males on both sides (P<0.001). Statistical differences between the sexes were also seen in relation to the following morphometric variables: height of the left IOF (P=0.007), width of the right IOF (P=0.004), and width of the left IOF (P=0.008), and the measurements were also larger among males. The IOF was present in all the crania and on both sides. It was morphometrically larger in males, on both sides.