The effect of facial expression on facial symmetry in surgically managed unilateral cleft lip and palate patients (UCLP).

AIM: To evaluate the symmetry of facial expression in surgically managed UCLP patients. MATERIALS AND METHODS: The study was conducted on 13 four-year-old children. Facial images were captured at rest and at maximum smile using stereophotogrammetry. A generic mesh, which is a mathematical facial mask consisting of a fixed number of indexed vertices, was utilised for the assessment of facial asymmetry. This was quantified by measuring the disparity between the left- and right-hand sides of the face after superimposing the original 3D images on their mirror copies. RESULTS: Residual asymmetries at rest were identified at the vermillion of the upper lip and at the nares with a deviation of the philtrum towards the scar tissue. Vertical and anteroposterior asymmetries were identified on the cleft side. At maximum smile, the asymmetry increased noticeably at the vermillion of the upper lip and at the alar base. In the mediolateral direction, the philtrum deviated towards the cleft side with a significant increase of the asymmetry scores. DISCUSSION: Asymmetry of the upper lip has significantly increased at maximum smile as a result of the upward forces of all perioral lifting muscles, which affected the lip directly. CONCLUSIONS: The innovation of this study is the measurement of facial asymmetry for the objective outcome measure of the surgical repair of UCLP. The philtrum was the main site of residual asymmetry, which indicates the need for refining the primary repair of the cleft lip. Further corrective surgery may be required.

Assessment of facial asymmetry before and after the surgical repair of cleft lip in unilateral cleft lip and palate cases.

This study was performed to assess facial asymmetry in patients with unilateral cleft lip and palate (UCLP) before and after primary lip repair. Three-dimensional facial images of 30 UCLP cases (mean age 3.7±0.8months) captured 1-2days before surgery and 4 months after surgery using stereophotogrammetry were analysed. A generic mesh - a mathematical facial mask consisting of thousands of points (vertices) - was conformed on the three-dimensional images. Average preoperative and postoperative conformed facial meshes were obtained and mirrored by reflecting on the lateral plane. Facial asymmetry was assessed by measuring the distances between the corresponding vertices of the superimposed facial meshes. Asymmetries were further examined in three directions: horizontal, vertical, and anteroposterior. Preoperatively, the philtrum and bridge of the nose were deviated towards the non-cleft side. The maximum vertical asymmetry was at the upper lip. The greatest anteroposterior asymmetry was at the alar base and in the paranasal area. The overall facial asymmetry improved markedly after surgery. Residual anteroposterior asymmetry was noted at the alar base, upper lip, and cheek on the cleft slide. In conclusion, dense correspondence analysis provided an insight into the anatomical reasons for the residual dysmorphology following the surgical repair of cleft lip for future surgical consideration.