Tomographic Pharyngeal Dimensions in Individuals with Unilateral Cleft Lip/Palate and Class III Malocclusion are Reduced When Compared with Controls

Objective The objective of this study was to three-dimensionally evaluate the pharyngeal dimensions of individuals with complete nonsyndromic unilateral cleft lip and palate (UCLP) using cone beam computed tomography. Design This was a cross-sectional prospective study. Setting The study took place at the Laboratory of Physiology, Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo, Bauru-SP, Brazil. Patients and Participants The control group (CON) consisted of 23 noncleft adults with class III malocclusion, and the cleft group (UCLP) consisted of 22 individuals with UCLP and class III malocclusion. Two subgroups of individuals with class III malocclusion as a result of maxillary retrusion with (UCLP'; n = 19) and without (CON'; n = 8) clefts were also assessed. Interventions Pharyngeal volume, pharyngeal minimal cross-sectional area (CSA), location of CSA, pharyngeal length, sella-nasion-A point angle (SNA), sella-nasion-B point angle (SNB), and A point-nasion-B point angle (ANB), and body mass index were assessed using Dolphin software. Main Outcome Measure The pharyngeal dimensions of UCLP individuals are smaller when compared with controls. Results Mean pharyngeal volume (standard deviation) for the UCLP patients (20.8 [3.9] cm3) and the UCLP’ patients (20.3 [3.9] cm3) were significantly decreased when compared with the CON (28.2 [10.0] cm3) and CON’ patients (29.1 [10.2] cm3), respectively. No differences were found in the pharyngeal minimal CSA, ANB, or pharyngeal length values between groups (CON versus UCLP and CON’ versus UCLP'). CSAs were located mostly at the oropharynx, except in the UCLP’ patients, which were mainly at the hypopharynx. Mean SNA in the UCLP (76.4° [4.6°]) and UCLP’ groups (75.1 [3.1°]) were significantly smaller than those in the CON (82.8° [4.1°]) and CON’ groups (78.6° [1.2°]). SNB values were statistically smaller only for the comparison of CON versus UCLP patients. Conclusion The pharynx of individuals with UCLP and class III malocclusion is volumetrically smaller than that of individuals with class III malocclusion and no clefts.