Changes on facial profile in the mixed dentition, from natural growth and induced by Balters' bionator appliance

Abstract

Objective: The purpose of this study was to evaluate the facial profile changes induced by Balters' bionator appliance in Class II division 1 patients, at mixed dentition stage.

Methods: The sample consisted of 28 pre-pubertal individuals at stages 1 and 2 of skeletal maturation (CVM), which were divided into two groups. The experimental group consisted of 14 individuals (7 boys and 7 girls, initial mean age of 8y12m) which were treated with Balters' bionator appliance for 14.7 months. The effects of treatment were compared to a control group of 14 subjects (7 boys and 7 girls, initial mean age of 8y5m) with Class II malocclusion, division 1, not orthodontically treated, which were followed up for 15.4 months. The statistical analysis was performed using Student's t test, at a significance level of 5%.

Results: The results showed that the Balters' bionator appliance promoted a significant increase on the mentolabial angle, in addition to demonstrating a tendency to reduce the facial skeletal convexity, to restrict the maxillary growth and to increase the nasolabial angle and the lower anterior facial height.

Conclusions: It can be concluded that the Balters' bionator appliance improved the facial profile of children treated at mixed dentition stage.

Keywords: Activator appliances; Angle Class II malocclusion; Cephalometry.