Effectiveness of comprehensive fixed appliance treatment combined with a Fatigue Resistant Device in Class II patients.

AIM: To assess the dental, skeletal, and soft tissue effects of comprehensive fixed appliance treatment combined with the Forsus Fatigue Resistant Device (FRD) in Class II patients. SUBJECTS AND METHODS: Thirty-two Class II patients (mean age 12.7 ± 1.2 years) treated consecutively with the FRD protocol, analyzed prospectively, and compared with a matched sample of 27 untreated Class II subjects (mean age 12.8 ± 1.3 years). Lateral cephalograms were taken before (T1) and at the completion (T2) of comprehensive therapy. The mean duration of comprehensive treatment was 2.4 ± 0.4 years. Statistical comparisons were carried out with the Student’s t-test (P < 0.05). The power of the study exceeded 0.90. RESULTS: The success rate was 87.5 per cent. The FRD group showed a significant restraint in the sagittal skeletal position of the maxilla (also at the soft tissue level), a significant increase in mandibular length, and a significant improvement in maxillomandibular sagittal skeletal relationships. The treated group exhibited a significant reduction in overjet and a significant increase in molar relationship. The lower incisors were significantly proclined and intruded, while the lower first molars moved significantly in a mesial and vertical direction. CONCLUSIONS: The FRD protocol is effective in correcting Class II malocclusions with a combination of skeletal (mainly maxillary) and dentoalveolar (mainly mandibular) modifications.