Objective : To clarify the short- and long-term effects of maxillary protraction (MP) in mixed dentition in patients with unilateral cleft lip and palate (UCLP). Design : Retrospective study. Setting : University of Tokyo Hospital. Patients and Intervention : Eleven Japanese patients with UCLP in mixed dentition were treated with MP and followed up until the completion of growth. Multibracket treatment had been performed after MP treatment in all patients. Main Outcome Measure : Lateral cephalograms taken before and after MP and after completion of growth were used. Posterior and anterior vertical reference lines (PV, AV) were used to measure the horizontal movements of point A, pogonion, and maxillary first molar (U6). SNA, SNB, ANB, maxillary and mandibular length, mandibular plane angle, Wits value, upper incisor inclination, overjet, and overbite were also measured. Results : Large variation was found in the effects of MP, and five patients eventually required orthognathic surgery. In average change with MP, the maxilla showed favorable forward growth. Point A had moved forward from PV but not AV. The mandible rotated backward. However, ANB and the Wits value did not improve. U6 moved forward, and the overjet improved. After MP, the skeletal Class III relationship became severe. Conclusions : MP was effective as an early treatment for UCLP patients. However, its effects showed large variation and were in conflict with facial growth. Conscientious explanation of the expected effects and associated problems should be given to the patients/parents before its application.
Keywords: cleft lip and palate; long-term follow-up; maxillary protraction.