RESUMO
OBJECTIVES: The aim of this study was to assess the effects of reverse headgear (RHG) treatment combined with rapid maxillary expansion (RME) on the trabecular structure of the mandibula using fractal dimension (FD) analysis. METHODS: Forty-four individuals with skeletal Class III malocclusion were selected from the archives and divided into two groups as patients who underwent treatment with RME + RHG (RHG-G, 22 patients) and untreated control group (C-G, 22 patients). The before (T0) and after (T1) treatment lateral cephalometric and panoramic radiographs were collected in the RHG-G and in the control group, radiographs obtained with similar time intervals were grouped as T0 and T1. Cephalometric and FD analysis was conducted on T0 and T1 lateral cephalometric and panoramic radiographs. The intragroup comparison of cephalometric and FD data was performed using paired t test and Wilcoxon Signed Ranks test, while independent t test and Mann-Whitney U test were used for intergroup comparison. RESULTS: C-G had higher FD values in the right mandibular corpus and left mandibular ramus values at T0 (P < .05). The only significant difference in the intragroup comparisons was detected in the FD values of the right mandibular corpus in the C-G (P < .05). No significant differences were found in the FD between the groups in any of the areas measured (P > .05). CONCLUSIONS: RME + RHG therapy did not cause any significant trabecular changes in the mandibula when compared to the control group.