Combined fixed-functional treatment of skeletal class II malocclusions with the EVAA appliance: a preliminary study

The aim of this study was to compare the skeletal and dental effects of the EVAA appliance with those of an activator appliance in growing children with skeletal Class II anomalies.

A total of 34 subjects with Class II anomalies were recruited for this study. They were divided into three groups: the EVAA group (n=13; mean chronological age: 11 years 9 months), activator group (n=13; mean chronological age: 11 years 8 months) and control group (n=8; mean chronological age: 10 years 8 months). Lateral cephalometric radiographs were taken at the beginning and end of functional therapy. Fixed orthodontic treatment was completed in the EVAA group. A statistical software program (SPSS 18) was used for one-way analysis of variance and multiple comparisons with the Duncan test.

We observed a significant decrease in the ANB, convexity, and 1┴NA (°), while a significant increase appeared in upper anterior facial height, posterior facial height, 1┴NB (mm), SN-lower occlusal plane values in the EVAA and activator groups after treatment (p<0.05). No significant difference in study parameters in the control group during the treatment period except for the increase in SNA and 1┴NA (mm) values (p<0.05) were observed. There were no significant differences between EVAA and activator treatment groups in terms of study parameters except for the articular angle, which was significantly higher in the EVAA group after therapy (p<0.05).

The effects of EVAA appliances were similar to those of activator treatment.