Dentoskeletal analysis of anteroposterior and vertical changes after use of marpe in patients in final stages of palatal suture fusion: double-blind, controlled, randomized clinical trial

Background: The adverse effects of anteroposterior and vertical changesafter mini-implant assisted rapid palatal expansion (MARPE) may compromise the indication of this treatment for dolicofacial and Class II patients. The aim of this study was to use cone beam computed tomography to evaluate the anteroposterior and vertical dentoskeletal alterations that occurred after palatal expansion with MARPE in patients in the final stages of midpalatal suture maturation. Methods: The sample was composed of 20 volunteers of both sexes, with maxillary atresia, mean age of 24.8 (±7.1) years, allocated to two groups (n= 10) according to suture maturation stage “D” or “E”. The following anteroposterior craniometric (SNA, SNB, A-Nperp, Pog-Nperp, 11.APog, 21.APog, 41.APog, 31.APog, 11-APog, 21-APog, 41-APog, 31-APog, 16-PtVr, 26-PtVl, 46-PtVr, 36-PtVl) and vertical (SN.PP, SN.MP, PP.MP, N-Me, N-ANS, S-PNS, ANS-Me, 16-PP, 26-PP, 46-MP, 36-MP). The measurements were evaluatedbefore treatment (T0) and immediately after transverse correction with maxillary expansion (T1) with VistaDent 3D software. The parametric data were submitted to the ANOVA test, and the non parametric type were analyzed by generalized linear models (α=0.05). Results: No statistically significant differences between the groups were observed, except for slight extrusion of the first molars in Group E (p<0.05). In both groups, the maxilla moved forward and the mandible, backwards and downwards, with retroinclination of the mandibular central incisors (p<0.05). In Group D, the maxillary first molars retracted (p<0.05). In Group E, the maxillary central incisors inclined towards the vestibular direction (p<0.05). Conclusion: Treatment with MARPE generated anteroposterior and vertical effects inherent to rapid maxillary expansion, irrespective of the level of suture fusion; however, the treatment does not lead to a significant clinical repercussion of increase in vertical height or posterior displacement of the mandible.