RESUMO
OBJECTIVE: Midface retrusion is a concern in patients with complete unilateral cleft lip and palate (CUCLP). Maxillary segment alignment may influence the prognosis after corrective surgery. This study assessed the association between maxillary segment alignment and interarch relationship observed in the early mixed dentition. The null hypothesis was that there is no relation between the initial alignment of cleft segments and the width of the cleft in the infant, and the early mixed dentition interarch relationship. SETTING AND SAMPLE POPULATION: The sample consists of 352 children with CUCLP treated at the Hospital for Rehabilitation of Craniofacial Anomalies/USP. MATERIAL AND METHODS: Dental models were obtained before lip repair at three months and at the age of six. Based on the first, the sample was then divided into two groups: anteroposterior aligned and anteroposterior misaligned maxillary segments. They were also divided into 4 groups according to the cleft width (Narrow, Medium, Wide and Very Wide). Interarch relationship was graded using the 5-year-old index. The statistical association was evaluated using the chi-squared test (P < .05). RESULTS: Cleft width was inversely related to interarch relationship in the early mixed dentition phase. Interarch relationship at the age of six was more favourable in children with misaligned maxillary segments than in children with aligned segments (P = .048). CONCLUSION: Five-year interarch relationship in patients with CUCLP is related to the anteroposterior relationship of infant maxillary segments and initial cleft width before primary surgeries. Wide alveolar clefts and sagittally aligned maxillary segments showed a worse interarch relationship in the early mixed dentition.