Assessment of the skull base, pterygomaxillary junction, and its association with the orbit in skeletal malocclusion and cleft lip/palate implications for Le fort I osteotomy.

BACKGROUND: This study aimed to evaluate the anatomical characteristics of the skull base and the pterygomaxillary junction (PMJ) in relation to the orbit in individuals with various skeletal deformitiesand cleft lip and palate (CLP).

METHODS: Cone beam computed tomography (CBCT) scans of patients classified into four groups (Class I, II, III, and CLP) were analyzed. Various anatomical measurements of the PMJ, skull base, and orbital structures were assessed. Statistical comparisons between groups were performed to identify significant morphological differences.

RESULTS: Significant variations in PMJ morphology were observed among the study groups. The mean anterior length was significantly greater in patients with CLP (p = 0.000), whereas the posterior length was greater in Class III patients (p = 0.042). The thinnest pterygomaxillary region was found in Class III patients (p = 0.002). The width of the maxillary tuberosity, the distance from the superior orbital fissure (SOF)-PMJ and the orbital canal (OC)-PMJ, and the distance between the medial and lateral pterygoid plates on both sides were the lowest in the CLP group (p < 0.05). The angle of the PMJ was the highest in the Class II group (p = 0.014), whereas the distance between the lateral plates at the hamulus level was the lowest in the Class II group. (p = 0.005) CONCLUSION: Our study highlights notable anatomical differences in the PMJ among individuals with skeletal malocclusion and CLP. These variations are clinically relevant for preoperative planning in Le Fort I osteotomy, particularly in reducing the risk of unfavorable fractures and ophthalmic complications. These findings underscore the importance of individualized surgical approaches based on anatomical assessments.