Morphological assessment of Le Fort I osteotomy in unilateral cleft lip and palate patients- part 2 - lateral nasal and septum osteotomy regions.

Anatomical variations in the lateral nasal wall and nasal septum osteotomies are of critical importance in patients with dentofacial deformities undergoing Le Fort I osteotomy. These structural differences may increase the risk of intraoperative complications. Therefore, this study aimed to evaluate the anatomical differences of the lateral nasal wall and nasal septum between individuals with unilateral cleft lip and palate(UCLP) and non-cleft controls. A total of 106 participants were included:53 with UCLP and 53 healthy individuals. From axial CBCT sections, linear measurements of three different regions of the lateral nasal wall(Length I, II, III) were obtained, and the corresponding angular measurements(Angles α and β) were calculated. In addition, the distance between the intended osteotomy line during septal osteotomy and the undesired osteotomy line close to the sphenoid sinus, as well as the angle between these two osteotomies(Angle X), were assessed. The results showed that the UCLP group had significantly lower values for Length I, II, III and Angle α compared with the control group, whereas Angle β was significantly higher in the UCLP group (p = 0.007).The distance between the intended and undesired osteotomy lines was also significantly lower in the UCLP group(p<0.001). No significant difference was found in Angle X between the groups(p=0.965). This study demonstrates distinct anatomical differences in the lateral nasal wall and nasal septum of UCLP patients and emphasizes the importance of planning the direction, depth, and safety margins of osteotomy lines according to individual anatomical variations. Preoperative evaluation with CBCT plays a crucial role in enhancing surgical safety and minimizing complication risks.