Morphometric assessment of greater palatine canal and foramen variations in cleft lip and palate patients using CBCT

Anatomical variation of the greater palatine canal (GPC) is critical for safe regional anesthesia and posterior maxillary surgery. This study aimed to evaluate GPC anatomy in cleft lip and palate (CLP) patients using cone-beam computed tomography (CBCT) to support safer clinical interventions.

Anatomical comparisons were performed between CLP patients and non-cleft controls using CBCT scans. Evaluated parameters included greater palatine foramen (GPF) width, linear distances from the GPF to surrounding anatomical landmarks (such as the pterygoid canal (PC), infraorbital foramen (IOF), occlusal plane, and midsagittal plane), angular measurements of the GPC (transverse and vertical angles, and the angle toward the pterygopalatine fossa), the number of lesser palatine foramina, and the position of the GPF relative to maxillary molars. Subgroup analyses were conducted within the CLP group based on cleft type (unilateral cleft side, non-cleft side, bilateral), age (≤16 vs. >16 years), and sex.

The study included 118 patients with CLP and 118 healthy controls. CLP patients demonstrated significantly longer PC-IOF distances and significantly shorter GPF-PC distances compared to controls (P < 0.001 for both). In addition, both transverse and vertical GPC angles were significantly greater in the CLP group (P < 0.001). Subgroup analysis revealed that bilateral CLP patients had lower PC-IOF distances and smaller vertical GPC angles compared to those with unilateral clefts (p = 0.018, p = 0.011).

CLP patients demonstrate anatomical variations in GPC morphology that may affect anesthetic access and surgical safety. These findings highlight the value of individualized CBCT-based planning in maxillary procedures.