Effect of palatal shape on dental arch relationships in unilateral cleft lip, alveolus, and palate

Abstract

INTRODUCTION: Palatoplasty is a critical surgery for restoring structure and function in patients with cleft palate, but surgical scarring is considered a major factor in maxillary growth deficiency and abnormal dental arch relationships. Palatal scars can significantly alter palatal morphology. The aim of this study was to investigate the relationship between palatal shape and dental arch relationships in children with complete unilateral cleft lip, alveolus, and palate (CUCLAP). METHODS: Palatal shape was analyzed using 239 landmarks on digital models of casts obtained from 50 children with CUCLAP (mean age 9.8 years, standard deviation [SD] 0.91 years; 34 boys) who underwent one-stage cleft repair at 8 months old (SD 2 months), and from 60 non-cleft controls (mean age 8.6 years, SD 1.2 years; 25 boys). Some CUCLAP patients had received simple orthodontic treatment prior to evaluation, and most had undergone alveolar bone grafting as part of their cleft management; the control group had no history of orthodontic treatment or bone grafting. Procrustes superimposition and principal component analysis were performed to characterize the sample; deviations in palatal shape were quantified as the Procrustes distance (ProcDist) from the average non-cleft palate. Dental arch relationships were scored twice with the GOSLON Yardstick by four assessors. A correlation analysis evaluated the relationship between the ProcDist and GOSLON score. Digitization error was assessed through repeat digitization of 25 UCLP cases. Kappa statistics were used to assess agreement among and within raters. RESULTS: Inter-rater agreement for GOSLON score ranged from κ = 0.64 to 0.82 (lower limit 95% confidence interval = 0.61), and intra-rater agreement ranged from κ = 0.66 to 0.88. Digitization error accounted for 4.81% of total variability. The mean GOSLON score was 2.95 (SD 0.83). The ProcDist correlated with the GOSLON score (R = 0.28; p = 0.045). CONCLUSIONS: Palatal shape is associated with dental arch relationships in CUCLAP, and geometric morphometric assessment of palatal deviation may complement existing occlusal indices in the evaluation of treatment outcomes. When automated, such techniques may offer an objective and reproducible tool for quantifying the degree of palatal deviation from a normative shape.