Long-term evaluation of maxillary expansion and facemask therapy: a controlled study

AIM: Long-term data on the effectiveness of maxillary expansion and protraction in Class III patients are lacking. The aim of this study was to evaluate the stability of maxillary expansion and facemask therapy (E/FM) in Class III patients at a long-term observation, compared with the effects of growth in well-matched untreated Class III controls. SUBJECTS AND METHOD: The treated group (TG) consisted of 21 patients (11 females, 10 males) with dentoskeletal Class III malocclusions treated with a two-phase protocol consisting of E/FM therapy followed by fixed appliance therapy, while the control group (CG) comprised 18 untreated subjects (12 females, 6 males) with similar dentoskeletal Class III features. Lateral cephalograms of both the TG and CG were analyzed at three timepoints, before treatment (T1); after two-phase treatment (T2); and long term (T3). All patients started treatment (T1) before the pubertal growth spurt (CS1 or 2, mean age 9.5 ± 1.6 years), and had completed active skeletal maturation at T3 (CS6, mean age 18.7 ± 2.1 years). RESULTS: At T3 the TG exhibited greater values for ANB angle, Wits appraisal, overjet and molar relationship when compared with the CG. No significant difference between the two groups was found for the changes occurring from T2 to T3. CONCLUSION: Favourable long-term dentoskeletal outcomes were induced by E/FM and fixed appliances in Class III patients. These outcomes remained stable at T3 in 72.5 per cent of the treated subjects. The untreated Class III malocclusion group did not show any tendency toward self improvement during the post-pubertal interval.