Dental Arch Relationship Outcomes of 5-Year-Olds Born With Unilateral Cleft Lip and Palate Following the Centralization of Cleft Services.

To investigate the interdental arch relationship outcomes of 5-year-old children with unilateral cleft lip and palate (UCLP) before and after centralization of cleft services in the United Kingdom (UK) using the modified Huddart-Bodenham index (MHBI) and to investigate any differences in MHBI by cleft laterality.

Retrospective cross-sectional study.

Evaluation of three-dimensional study models of children with a complete UCLP.

All available 5-year-old orthodontic study models of participants with UCLP from the precentralization Clinical Standard Advisory Group (CSAG n = 107) and postcentralization cleft care UK (CCUK n = 195) studies. The models were also grouped by cleft laterality (left and right sided).

Differences between the interdental arch relationship outcomes were assessed using the MHBI. This index scored the buccal/palatal or labial/palatal relationships of 8 maxillary deciduous teeth with the opposing mandibular dentition. The anterior segment, buccal cleft segment, and noncleft segment scores were calculated and combined to calculate the MBHI total arch scores.

Inter and intraexaminer reliability demonstrated high levels of agreement. Statistically significant differences in the anterior segment, buccal noncleft segment, and total arch MHBI scores were found, with postcentralization CCUK performing better. Right-sided UCLP had statistically significantly better buccal cleft segments, but no differences were found for the other MBHI segments or total arch scores.

There were improved interdental arch relationships postcentralization of cleft services in the United Kingdom. Cleft laterality differences were limited to the buccal cleft segment with right-sided UCLP having better MBHI scores.