Characteristics and dimensions of the infraorbital canal: a radiographic analysis using cone beam computed tomography (CBCT)

Abstract

Purpose: To analyze morphological characteristics and dimensions of the infraorbital canal-groove complex using cone beam computed tomography (CBCT), and to evaluate its relationship with adjacent anatomical structures.

Methods: This retrospective study included CBCT scans of 100 patients taken between January and May 2014. Linear measurements of the infraorbital canal (IOC), the infraorbital groove (IOG) and the infraorbital canal-groove complex (IOC/G) were performed. Morphological variants of the IOC related to the maxillary sinus were classified into three types depending on the extent of protrusion of the canal into the sinus. Angles between the IOC and specific landmarks were measured to determine the direction of the IOC relative to the axial (A-ant) and sagittal (A-horiz) planes.

Results: A total of 127 IOCs were analyzed. The mean length of the IOC/G was 29 ± 3.0 mm. This value comprised the mean distances of the IOC (24.4 ± 2.9 mm) and the IOG (4.6 ± 1.7 mm). For the different types of IOC morphology, Type 1 (IOC embedded in maxillary sinus roof) was the most common (n = 87, 68.5%). The mean angles of A-ant and A-horiz measured 48.9° ± 7.5° and 20.3° ± 7.9°, respectively.

Conclusion: Knowledge of the IOC/G morphology and its variants is important for the prevention of infraorbital nerve injury due to anesthesia or surgical interventions in this area. The presented data of anatomical characteristics of the IOC/G could be helpful for the planning of surgeries in the maxillary region by means of CBCT imaging.

Keywords: Cone beam computed tomography; Infraorbital canal; Infraorbital canal-groove complex; Infraorbital groove; Maxillary bone.