Nasolabial shape and aesthetics in patients with cleft lip and palate: analysis of 3D facial images.

Background/objectives: In individuals with cleft lip and palate, nasolabial asymmetry and dysmorphology are associated with lower aesthetic ratings, though this relationship remains unclear. This study examines how deviations in nasolabial shape from the average affect aesthetic ratings.

Materials/methods: 3D stereophotogrammetric images were taken from 53 children with unilateral cleft lip and palate (UCLP) (34 boys, 19 girls; mean age: 10.5 ± 0.6 years) and 53 age and sex-matched children without cleft. UCLP repair was performed by three experienced surgeons in a single stage at 8.2 ± 2.3 months. An average 3D nasolabial shape model of noncleft individuals was created via geometric morphometrics with 10 fixed points and 100 semilandmarks. The Procrustes distances of the noncleft average shape from each cleft shape quantified nasolabial dysmorphology, while 15 laypersons rated nasolabial aesthetics on a 100-mm visual analogue scale (VAS; lower scores = poorer aesthetics). Internal rater-consistency was assessed via the intraclass correlation coefficient (ICC). Correlation analysis examined the relationship between aesthetics and nasolabial dysmorphology in the cleft group.

Results: The mean ICC of 0.85 (95% CI: 0.78-0.91) indicated high consistency among the raters. The average aesthetic rating for the cleft group was 42.2 ± 16.5. The mean Procrustes distance was 0.0993 ± 0.0205. Greater deviation from the average noncleft shape was associated with lower aesthetic ratings (Pearson's r = -0.282, p = 0.041).

Limitations: This single-centre, retrospective study may have selection bias and limited generalizability, with a predominantly prepubertal sample.

Conclusions/implications: Nasolabial aesthetics is influenced by the degree of deviation from the average noncleft shape, although this relationship explains only a small portion of the variance (R2 = 0.08). Other factors likely contribute to nasolabial aesthetic ratings.