A quantitative three-dimensional assessment of soft tissue facial asymmetry of cleft lip and palate adult patients

The three-dimensional coordinates of 23 selected soft-tissue facial landmarks were digitized on 18 cleft lip and palate (CLP) white patients (11 male and 7 female patients aged 19-27 years) and 161 healthy controls (73 female and 89 male subjects aged 18-30 years) by an electromagnetic instrument. Facial asymmetry was quantified by detecting a plane of symmetry and the centers of gravity (CG) of the right and left hemifaces and by calculating the distance between the two CG (distance from symmetry [DFS]). Both absolute (millimeters) and percentage (of the nasion center of gravity distance) DFS was obtained. The asymmetry of single landmarks was also quantified. Overall, asymmetry in operated CLP patients appeared only moderately larger than that measured in the healthy reference population, with the largest value being only 5% larger than the maximum normal asymmetry. Female patients had a somewhat larger lateral asymmetry than male patients, and unilateral CLP patients (particularly the men) were more asymmetrical than bilateral CLP patients. Pronasale and subnasale landmarks were asymmetrical in 8 patients, whereas endocanthion, zygion, cheilion, and gonion landmarks were symmetrical in all patients. In conclusion, the facial soft-tissue structures of CLP patients operated on as adults were only moderately more asymmetrical than those measured in a reference group of the same age, sex, and ethnicity.