Preliminary Analysis of the 3-Dimensional Morphology of the Upper Lip Configuration at the Completion of Facial Expressions in Healthy Japanese Young Adults and Patients With Cleft Lip

PurposeTo develop criteria for the analysis of upper lip configuration of patients with cleft lip while they produce various facial expressions by comparing the 3-dimensional (3D) facial morphology of healthy Japanese adults and patients with cleft lip.Patients and MethodsTwenty healthy adult Japanese volunteers (10 men, 10 women, controls) without any observed facial abnormalities and 8 patients (4 men, 4 women) with unilateral cleft lip and palate who had undergone secondary lip and nose repair were recruited for this study. Facial expressions (resting, smiling, and blowing out a candle) were recorded with 2 Artec MHT 3D scanners, and images were superimposed by aligning the T-zone of the faces. The positions of 14 specific points were set on each face, and the positional changes of specific points and symmetry of the upper lip cross-section were analyzed. Furthermore, the configuration observed in healthy controls was compared with that in patients with cleft lip before and after surgery.ResultsThe mean absolute values for T-zone overlap ranged from 0.04 to 0.15 mm. Positional changes of specific points in the controls showed that the nose and lip moved backward and laterally upward when smiling and the lips moved forward and downward medially when blowing out a candle; these movements were bilaterally symmetrical in men and women. In patients with cleft lip, the positional changes of the specific points were minor compared with those of the controls while smiling and blowing out a candle. The left-versus-right symmetry of the upper lip cross-section exceeded 1.0 mm in patients with cleft lip, which was markedly higher than that in the controls (0.17 to 0.91 mm). These left-versus-right differences during facial expressions were decreased after surgery.ConclusionBy comparing healthy individuals with patients with cleft lip, this study has laid the basis for determining control values for facial expressions.