Is the Nasolabial Region Symmetric in Individuals With Cleft Lip and Palate?

To assess the nasolabial symmetry in smile and resting position in individuals with nonsyndromic unilateral cleft lip and palate (UCLP) and compare with Class I individuals without cleft lip and palate (CLP).

Frontal photographs of 40 individuals with UCLP (mean age 14.30 ± 0.25 years; 20 female, 20 male) and 40 skeletal Class I individuals without CLP (mean age 14.60 ± 0.34 years; 20 female and 20 male) were examined. Bland-Altman Levels of Agreements, Mann-Whitney U test, independent sample t-test were conducted, and intraclass correlation coefficients (ICCs) were calculated for statistical analysis.

Differences in the transverse lip distance (d-d') and vertical lip height at crista philtri (e-e') were lesser in the UCLP group at smile (P = .001; P = .005, respectively). When comparing the differences in these measurements at rest between control and UCLP groups, vertical lip height was longer at crista philtri (e-e') (P = .014), crista philtri was more laterally located (f-f') (P = .002), and the transverse lip distance was greater (d-d') (P = .004) in the UCLP group. Distance of the crista philtri to the midline of the face (f-f') (P = .007) were higher in the UCLP group during smiling compared to control group.

Nasolabial region asymmetry in smiling and rest position in individuals with UCLP was significantly different from the control group. However, the asymmetry in the nasolabial region, which is more evident in the resting position in individuals with UCLP, decreases during smiling.