Naso-alveolar Asymmetry in Unilateral Cleft Lip and Palate Patients—CT Analysis of the Paranasal Region

Secondary deformities to the midfacial area in adolescence and adulthood are common sequelae after primary cleft lip and palate repair and lead to significant functional, aesthetic and psychosocial challenges. Treatment for patients with normal occlusion or treated malocclusion and remaining midfacial hypoplasia includes autologous and alloplastic augmentation of the maxilla. Because of the great variation of deformities, accurate evaluation is essential for appropriate treatment planning. To provide insights in the altered midfacial anatomy in cleft patients, a retrospective computed tomography morphologic analysis of the anterior projection of the maxilla in the paranasal region, soft tissue thickness, and relation of soft tissue to bony landmarks was performed in adolescent, unilateral, non-syndromic complete cleft and palate patients. The anterior projection of the maxilla was very variable with the cleft side bone surface being more anterior relative to the non-cleft side in some patients. Soft tissue thickness was not significantly different between cleft and non-cleft side. The lateral distance from the most anterior point of the maxilla to subalare was significantly smaller on the cleft side as compared with the non-cleft side. The authors' study demonstrates that in cleft lip and palate patients midfacial anatomy with regards to maxilla projection at the pyriform aperture is very variable making accurate evaluation of the bone morphology and an individualized treatment plan a prerequisite for successful correction of nasomaxillary deformities.