[Early treatment of Class III: a long-term cohort study]

The aim of this comparative retrospective short- and long-term study was to evaluate the interceptive treatment in Class III malocclusion in daily orthodontic practice. The sample was composed of 69 children divided into two groups according to the interceptive treatment applied: 31 children in group F (facial mask) and 38 in group M (interceptive fixed appliance). A Pancherz cephalometric analysis was carried out on the lateral head films at the start of the study (t(0), after the active treatment (t(1) and 29 months after t(1) (t(2). The two groups were compared at the beginning of the study by t-test and chi-squared test: there were no difference between groups M and F except for facial divergence, which was greater in group M. Long-term comparison (interceptive and post-interceptive stage i.e. six years) showed that (i) overjet was corrected in each group: molar discrepancy was stable in both groups, (ii) alveolar discrepancy was stable and (iii) antero-posterior discrepancy was not improved in either group. At t(2) there were no differences, either qualitative or quantitative between groups M and F. In the end, more than 80% of the children did not need an orthognathic surgery.