Abstract
The purpose of this study was to investigate effects of the maxillary protrac tor on craniofacial growth of patients with operated complete unilateral cleft lip and palate(UCLP).
The subjects consisted of three males and four femal es with operated UCLP and two males and four females of non-cleft cases with mandibular protrusion and undergrowth of the midface. The maxillary protractor was used for both UCLP and non-cleft patients. The lateral cephalograms were obtained before treatment and after normal occlusal relation was acquired or at the phase of treatment when the protractor was used at least two years. The control for the UCLP group was comprised of the orthodontically untreated UCLP patients and the control for non-cleft group was obtained from the growth study materials of Department of Orthodontics, Faculty of Dentistry, Osaka University. The age and sex of each control group were matched with the subjects used in this study.
The following results were obtained.
1. The maxillary protractor was found to be effective for the forward growth of the maxillary complex in both UCLP and non-cleft groups. However, its effect was less in the UCLP group than the non-clef t group.
2. The backward rotation of the mandible, which was generally observed in the non-cleft group as the response to the chin cup of the maxillary protractor, was not always found in the UCLP group.
