Long-term effects of lip repair on dentofacial morphology in patients with unilateral cleft lip and palate.

Objective: Lateral cephalograms from the growth archive of the Sri Lankan Cleft Lip and Palate Project were analyzed in a cohort design to study the long-term effects of lip repair on dentofacial morphology in patients with unilateral cleft lip and palate.

Methods: A total of 71 patients were recruited, including 23 adult patients with nonsyndromic unilateral cleft lip and palate without surgical repair and 48 adult patients with nonsyndromic unilateral cleft lip and palate who had lip repair, but without management of alveolus or anterior vomer. The design utilized exact matching on ethnicity and statistical control for gender and age.

Conclusions: The data support the hypothesis that lip repair primarily produces a bone-bending effect on the anterior maxillary alveolus (alveolar molding), accompanied by controlled uprighting of maxillary incisors, and secondarily produces a bone-remodeling effect (bone resorption) in the base of the anterior maxillary alveolus. When analyzed by the age at lip repair and the surgeon who performed lip repair, early lip repair produced a greater bone-remodeling effect than did late lip repair, and variation in the surgeon who performed lip repair had an insignificant impact on dentofacial morphology after adjusting for covariates.