A prospective study of the treatment effects of a removable appliance with palatal crib combined with high-pull chincup therapy in anterior open-bite patients.

INTRODUCTION The aim of this prospective clinical study was to cephalometrically investigate the dentoalveolar and skeletal changes produced by a removable appliance with palatal crib associated with high-pull chincup therapy in children with Angle Class I anterior open-bite malocclusions. METHODS Thirty children with initial mean age of 8.61 years and mean anterior open bite of 4.01 mm were treated with removable appliances with palatal crib associated with chincup therapy for 12 months. A control group of 30 subjects with initial mean age of 8.33 years and mean anterior open bite of 3.95 mm with the same malocclusion was followed for 12 months for comparison. RESULTS The removable appliance with palatal crib combined with vertical chincup did not yield significant changes in maxillary and mandibular skeletal components, maxillomandibular relationship, or vertical facial pattern. Overall, effects in the treated group were exclusively dentoalveolar. Open bite in the treatment group showed a mean closure of 5.01 mm (SD +/- 1.73). CONCLUSIONS The association of high-pull chincup therapy with a removable appliance and palatal crib provided no positive skeletal influence on the vertical facial pattern of patients treated for open bite in the mixed dentition.