Table 1.

Electronic databases used and search strategy

Database	Search strategy Key words
PubMed	Rapid palatal expansion(s) OR
http://www.ncbi.nlm.nih.gov/pubmed/	Rapid maxillary expansion(s) OR
	RME OR
Scopus	Rapid maxillary expansion treatment(s) OR
www.scopus.com/home.url	Rapid palatal expansion treatment(s) OR
	RPE OR
	Rapid palatal disjunction(s) OR
	Rapid maxillary disjunction(s) AND
	Pharyngeal airway changes OR
	Upper airway changes AND
	Cone Beam Computed Tomography OR
	CBCT