Quantification of Skeletal Paranasal Asymmetry in Patients With Unilateral Cleft Lip and Palate

Patients with unilateral cleft lip and palate (UCLP) often exhibit asymmetric paranasal flatness of soft tissues. Despite clinical recognition of this asymmetry, skeletal paranasal asymmetry remains poorly quantified. Measuring skeletal landmark asymmetries can aid in planning surgical maxillary yaw corrections that simultaneously enhance paranasal symmetry and maxillary dental midline position. This study aims to quantify skeletal paranasal asymmetry in patients with UCLP. Skeletally mature patients with complete UCLP who were orthodontically prepared for orthognathic surgery between 2014 and 2023 were included in this study. Presurgical CBCTs were analyzed using Dolphin 3D. Anterior-posterior discrepancies between affected and unaffected sides were measured at the most lateral point of piriform aperture (PA) and 15 mm lateral to PA (15PA). A one-sample t test was conducted. Analysis of 30 patients (mean age 18-8 y, 17 male, 13 female, 20 left-sided, 10 right-sided) was completed. On the affected side, PA and 15PA were positioned 3.8 mm ( P <0.05) and 2.4 mm ( P <0.05) more posteriorly, respectively. These results suggest that skeletal paranasal asymmetry should be assessed during the pretreatment stage, as presurgical orthodontics should maintain a maxillary midline deviation toward the affected side when yaw correction is indicated. This approach facilitates simultaneous correction of piriform projection and midline alignment during surgery and may reduce the need for secondary procedures, such as malar implants or fat injections, which add cost and morbidity. This study confirms skeletal paranasal asymmetry in patients with UCLP and establishes a standardized method for measuring these deficiencies using CBCT-based skeletal landmarks.