Different Characteristics of Maxillary Development and Bone Defect: An Observation from Unilateral Cleft Lip Patients With Complete and Incomplete Cleft Palate

This study aimed to observe the difference in the maxillary development and bone defect between unilateral cleft lip and palate (UCLP) patients with various severities of palate cleft after adolescent period. A total of 91 UCLP patients accompanied with alveolar cleft, 49 complete cleft palate (CCP) patients, and 42 incomplete cleft palate (ICCP) patients, ages between 14 and 30, were included for cephalometric analysis and image segmentation utilizing their computed tomography data. Paired sample t tests were performed to reveal the difference between the cleft side and the noncleft side. Independent sample t tests and χ2 tests were conducted to compare the CCP group and ICCP group. Length and anterior height of both maxilla and alveolar were significantly smaller on the cleft side in 2 groups. Maxillary length of the noncleft side was similar between 2 groups, but significantly reduce in the cleft side in the CCP group. The CCP group showed inadequate bilateral alveolar development in sagittal and transverse dimensions with increased bone defect volume and surface area. Significantly smaller ANB and SNA, and a higher prevalence of class III occlusal relation were found in CCP patients (63.3%) compared with ICCP patients (19.0%). Compared with ICCP, CCP patients were more likely to present smaller maxilla and severe bone defects in the alveolar process. CCP showed significantly more evident maxillary retrusion and malocclusion relations.