Objective: To evaluate the use of Class III Twin Blocks for the early treatment of Class III malocclusion. Design: Retrospective analysis. Subjects and Method: 14 subjects were consecutively treated with a modified version of the Class III Twin Block appliance. Lateral cephalometric radiographs taken at the start and end of treatment were assessed digitally. Results: The mean age of subjects was 10 years and mean treatment time was 6.6 months. The cephalometric analysis of changes during

more »

... nt shows proclination of the upper incisors [mean 5.1°, SD 5.1], retroclination of the lower incisors [mean Ϫ4.5°, SD 3.9], reduction in angle SNB [mean Ϫ1.3°, SD 1.8] and an increase in the maxillary/ mandibular planes angle (mean 2.1°, SD 2.2]. Average cephalometric digitizations and photographs of a clinical case are shown. Conclusions: Class III Twin Blocks can be used successfully for early treatment of Class III malocclusion. A randomly allocated prospective study is required to fully evaluate the efficacy of this appliance. Abstract Index words: Class III, Twin Blocks, Function Regulator III