Velopharyngeal variations in relatives of cleft-affected individuals.

Eighteen families each with two or more cleft lip and palate patients were studied by speech cephalometry for evidence of velopharyngeal inadequacy (VPI). With this total of 56 persons, three groups were recognized: 1) patients with cleft lip only (N = 7), 2) unaffected sibs of CL(P) probands and the unaffected parents with the positive clefting history on their side of the family (N = 33), and 3) unaffected parents with negative CL(P) history to their side of the family (N = 16). The latter served as controls. The velopharyngeal mechanism in function was evaluated by voicing the fricative/S/. The results showed no significant differences in the length of either the resting soft palate or pharyngeal depth among the three groups. Even though a significant (P less than 0.01) increase in soft palate length while voicing /S/ was found in group 2 relatives compared to group 3 controls, the failure to find differences in either resting palate length or pharyngeal depth coupled with a failure to demonstrate VPI in group 2 subjects by speech testing leaves the value of this observation uncertain.