The effect of growth of nasopharyngeal structures in velopharyngeal closure in patients with repaired cleft palate and controls without clefts: a cephalometric study.

To clarify the changes with growth of nasopharyngeal structures involved in velopharyngeal closure, a cross-sectional study from early childhood to puberty was carried out in 61 patients with repaired unilateral cleft lip and palate showing complete velopharyngeal closure (cleft group) and 82 controls without clefts (control group). Measurements of the nasopharyngeal area were derived from a coordinate system and landmarks on lateral cephalograms, and results were analysed by multivariate analysis and t test. The adequate ratio (velar length to pharyngeal depth ratio) in the control group was maintained at a stable value, indicating that the ratio around 1.3 would be standard to maintain velopharyngeal closure. The vertical position of posterior maxilla, pharyngeal depth and velar length in the cleft group showed a different pattern of growth from those in the control group. There was, however, characteristic growth in both groups for maintenance of velopharyngeal closure.