Effects of Rapid Maxillary Expansion on Upper Airway Parameters in Children With Unilateral Cleft Lip and Palate: A Cone-Beam Computed Tomography (CBCT) Study

Objectives To evaluate the effect of rapid maxillary expansion (RME) on nasopharyngeal dimensions in children with unilateral cleft lip and palate (UCLP). Design A prospective case-series longitudinal study. Setting Orthodontic Department, School of Dental Sciences. Participants Forty-eight children (30 males and 18 females) aged 8 to 10 years old with UCLP who had maxillary transverse constriction and need maxillary expansion. Intervention RME followed by retention phase. Main outcome Changes in 3-dimensional nasopharyngeal parameters after RME using cephalometric radiographs and cone-beam computed tomography (CBCT). Results The CBCT analysis revealed that the nasal cavity increased by 1907 mm 3 ( P < .001), the nasopharynx (NP) increased by 707 mm 3 ( P = .027), the minimum cross-sectional area increased by 29.98 mm 2 ( P < .001), and the distance between the right and left maxillary sinuses increased by 7.98 mm ( P < .001), although the change in the sinus volume was insignificant ( P > .05). Cephalometric measurements revealed a statistically significant inferior dislocation of the maxilla after treatment (S-S1, P = .024; N-ANS, P = .017), increase in the inferior anterior and posterior facial height (S-Go, P = .017; ANS-Me, P = .041; N-Me, P = .020). Conclusion RME treatment increased some nasopharyngeal dimensions in children with UCLP and maxillary constriction.