Palatal morphology in unilateral cleft lip and palate patients: Association with infant cleft dimensions and timing of hard palate repair.

Abstract

To assess the impact of cleft severity and timing of hard palate repair on palatal dimensions in unilateral cleft lip and palate (UCLP) children. Single-centre analysis within a multicenter RCT of primary surgery; 122 UCLP randomized to early hard palate closure (EHPC) at 12months or delayed hard palate closure (DHPC) at 36months; 28 frequency-matched controls. Linear measurements of palatal height, width and length were performed on 116 digital models of UCLP subjects (8.21years, SD=0.53) and 28 models of non-cleft individuals (8.44years SD=0.72). Cleft dimensions at infancy (mean 1.8months) were considered. In a pilot study, shell-to-shell distances between the 3D cleft palate objects and a reference mesh were calculated and differences between the groups assessed. Morphological differences were visualized using colour mapping. Compared to controls, UCLP subjects presented a higher palate at the level of the anterior scar (P=0.002), but generally a lower palate in the middle region (P<0.001). Comparing UCLP subgroups, the DHPC subjects showed a flatter palate posteriorly (P=0.048) and the EHPC group exhibited more transversal constriction (P=0.003 at M1 level). 3D analysis revealed a shallower palate in the DHPC group both in the middle (P=0.002) and the posterior part (P=0.008). Anterior cleft severity correlated negatively with palatal height (P=0.01). Unilateral cleft lip and palate palates differ from controls in width and height. DHPC may represent an advantage for the transversal dimension, but a disadvantage for palatal height. Infant cleft dimensions partially explain differences in palatal height.