RESUMO
OBJECTIVE: To add to the data for long-term reverse pull headgear (RPHG) outcomes and further explore possible variables that could be predictors of long-term failure. MATERIALS AND METHODS: Cephalometric radiographs of 41 Class III malocclusion children treated with RPHG (face mask) were evaluated before and immediately after treatment; at 5 years posttreatment; and, for 18 patients, at 10 years posttreatment. Patients were assigned to success or failure groups according to positive or negative overjet at the longest available recall. RESULTS: Seventy-five percent of the patients maintained positive overjet, whereas 25% outgrew the correction. In a stepwise discriminant analysis, a large mandible and vertical positioning of the maxilla and mandible so that mandibular growth would be projected more horizontally were the major indicators of unfavorable later mandibular growth. Patients who experienced downward-backward rotation of the mandible during RPHG treatment were more likely to be categorized in the failure group. The age at which treatment began had no effect on long-term success and failure for patients younger than 10 years, but the percentage of successful treatment decreased after that age. CONCLUSIONS: When RPHG treatment is used for all but the most obviously prognathic children to correct anterior cross-bite in the early mixed dentition, positive overjet is maintained long-term in 70%-75% of cases, whereas 25%-30% of cases relapse into reverse overjet mainly because of increased horizontally directed and often late mandibular growth. Up to age 10, the time at which RPHG treatment began does not appear to be a major factor in long-term success in maintaining positive overjet.
