Submucous cleft palate: variations in bony defects of the hard palate.

We have analysed bony defects of the hard palate in patients with submucous cleft palate to find out whether velopharyngeal insufficiency (VPI) is dependent on the extent of these defects. We evaluated the maxillofacial structures associated with cleft palate by 3-dimensional computed tomography (CT) in 23 children diagnosed with submucous cleft palate. Bony defects of the hard palate were divided into Type I, defined as absent posterior nasal spine (n=12), Type II, V-shaped bony notch (moderate, n=7), and Type III, as bony defect extending into the incisive foramen (severe, n=4) defects, respectively. VPI was found in 10, 3, and 4 patients, respectively. Neither VPI nor the degree of bifid uvula was significantly associated with the types of bony defects.