Functional outcomes of cleft lip surgery. Part II. Quantification of nasolabial movement

Objective: To explore nasolabial movements in participants with repaired cleft lip and palate. Design: A parallel, three-group, nonrandomized clinical trial. Subjects: Group 1 = 31 participants with a cleft lip slated for revision surgery (revision), group 2 = 32 participants with a cleft lip who did not have surgery (nonrevision), and group 3 = 37 noncleft control participants. Methods: Three-dimensional movements were assessed using a video-based tracking system that captured movement of 38 landmarks placed at specific sites on the face during instructed maximum smile, cheek puff, lip purse, mouth opening, and natural smile. Measurements were made at two time points at least 1 week and no greater than 3 months apart. Summary measurements were generated for the magnitude of upper lip, lower lip, and lower jaw movements and the asymmetry of upper lip movement. Separate regression models were fitted to each of the summary measurements. Results: Lateral movements of the upper lip were greater than vertical movements. Relative to the noncleft group, the revision and nonrevision groups demonstrated 6% to 28% less upper lip movements, with the smiles having the most restriction in movement and greater asymmetry of upper lip movement. Having an alveolar bone graft further increased the asymmetry, while a bilateral cleft lip decreased the asymmetry. Lower jaw movement caused a small increase in upper lip movement. Conclusions: The objective measurement of movement may be used as an outcome measure for cleft lip surgery.