Velar ascent and morphological factors affecting velopharyngeal function in patients with cleft palate and noncleft controls: a cephalometric study.

This study compares velar ascent and morphological factors affecting velopharyngeal function between patients with repaired cleft palate and noncleft controls from early childhood to puberty. Lateral cephalograms obtained at rest and during blowing from 61 patients with repaired unilateral cleft lip and palate (cleft group) and 82 noncleft controls (control group) were divided into four developmental stages according to age and were studied cross-sectionally. Indices of nasopharyngeal area were derived from a coordinate system and landmarks on lateral cephalograms. The cleft group had lesser velar ascent, more posterosuperior position of the posterior maxilla, shorter velar length, and lesser pharyngeal depth than did the control group. There was a strong correlation between the vertical position of the posterior maxilla and the pharyngeal depth in the cleft group. Discriminant analysis revealed that the cleft group could be discriminated from the control group primarily on the basis of pharyngeal depth, velar length, and velar ascent. Our results suggest that the posterosuperior position of the posterior maxilla in patients with repaired cleft palate, resulting in reduced pharyngeal depth, represents an effort to facilitate velopharyngeal closure by means of shorter velar length and lesser velar ascent.