Changes in the Mandible Following Rapid Maxillary Expansion in Children with Class II Malocclusion: A Systematic Review

Objective: The aim of this systematic review was to determine whether rapid maxillary expansion (RME) allows favorable changes in the mandible during the treatment of class II malocclusion before the growth spurt. Methods: A search of Pubmed/Medline, the Science Direct, and the Google Scholar database was performed. The keywords used were: orthodontics, rapid maxillary expansion, class II, and growing patients. Relevant articles were assessed for quality according to Cochrane guidelines, and then changes in SNA, SNB, ANB, NL-NSL (or SN-SNP.SNA), and ML-NSL (or SN-Go-Gn) relationships were analyzed. Results: The selection process brought forth five articles, including 162 patients (91 females, 71 males) for detailed analysis. The quality of the evidence (GRADE) for comparisons and outcomes was assessed as moderate for SNB and ANB and as low or very low for other variables. Conclusions: The results of this systematic review showed that there is a small body of moderate-quality evidence for statistically and clinically favorable changes in SNB and ANB angles and a small body of low-quality evidence for changes in vertical parameters after RME.