An innovative analysis of nasolabial dynamics of surgically managed adult patients with unilateral cleft lip and palate using 3D facial motion capture

Abstract

Aim: To compare dynamic nasolabial movement between end-of-treatment cleft and a matched non-cleft group in adult patients.

Materials and methods: Thirteen treated adult participants with unilateral cleft lip and palate had images taken using a facial motion capture system performing a maximum smile. Seventeen landmarks were automatically tracked. For each landmark pair, on either side of the midline, changes in the x, y, and z directions were used to analyze the magnitude of displacement and path of motion. An asymmetry score was developed at rest, mid-smile, and maximum smile to assess the shape of the mouth and/or nose.

Results: At maximum smile, displacement of right and left cheilion was clinically and statistically (p < 0.05) less in the cleft group. The lip asymmetry score was greater (p < 0.05) at each time point in the cleft group using the clinical midline. Using Procrustes superimposition, the differences were significant (p < 0.05) only at rest and mid-smile. The alar bases were displaced significantly less (p < 0.05) in the z direction in the cleft group. The asymmetry score of the alar base was significantly higher using the clinical midline than using Procrustes superimposition in patients with cleft conditions (p < 0.001). In the cleft group, at maximum smile, the right and left cristae philter moved significantly less (p < 0.05) in the x and z directions.

Conclusions: There was an increase in asymmetry score of the corners of the mouth and alar bases from rest to maximum smile. The lips were similar in shape but oriented differently in the faces of patients with cleft conditions than in individuals without those conditions.