Does rapid maxillary expansion change natural head position in children with maxillary constriction? A systematic review and meta-analysis

Abstract

Objective: a systematic review was performed to evaluate the natural head position (NHP) in children with maxillary constriction before and after rapid maxillary expansion (RME). Material and Methods: a comprehensive search was carried out in the MEDLINE via PubMeb, Scopus, Web of Science, LILACS, BBO and Cochrane Library and SIGLE without restrictions. The annual conference of the IADR abstracts (1990–2017) and unpublished and ongoing trials registry were also searched. Dissertations and theses were searched using the ProQuest Dissertations and “Periódicos CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) Theses Databases”. The studies compared the natural head position in patients submitted rapid maxillary expansion (RME) and untreated patients both with maxillary constriction. Results: a total of 3023 studies were identified, three remained in qualitative study and all these studies were considered at “unclear” risk of bias in the key domains. Only two studies presented similar data to be included in the meta-analysis. Both studies evaluated the natural head position, through the angle between nasion-sella line and true vertical (SN-Ver). The meta-analyses demonstrated that after 12 months follow-up, the SN-Ver angle decreased by 3.39 degrees (95% confidence interval [CI]=0.57 to 6.21; p=0.02). Conclusion: the RME promoted increase in SN-VER angle in child after 12 months for intervention; however, there are few studies in the literature about this topic, and there is a need of further well-designed trials to investigate this alteration.