Table 1. Electronic search strategy.

Database	Search strategy
CENTRAL (The Cochrane Library)	#1 orthodontic* OR orthodontic tooth movement" OR "orthodontic Treatment" OR "orthodontic Therapy" #2 accelerat* OR rapid* OR short* OR speed* OR fast #3 (surgical OR invasive OR minimally invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #4 (non-surgical OR non-invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #5 #1 AND #2 #6 #3 AND #5 #7 #4 AND #5
EMBASE	#1 orthodontic* OR orthodontic tooth movement" OR "orthodontic Treatment" OR "orthodontic Therapy" #2 accelerat* OR rapid* OR short* OR speed* OR fast #3 (surgical OR invasive OR minimally invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #4 (non-surgical OR non-invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #5 #1 AND #2 #6 #3 AND #5 #7 #4 AND #5
PubMed	#1 orthodontic* OR orthodontic tooth movement" OR "orthodontic Treatment" OR "orthodontic Therapy" #2 accelerat* OR rapid* OR short* OR speed* OR fast #3 (surgical OR invasive OR minimally invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #4 (non-surgical OR non-invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #5 #1 AND #2 #6 #3 AND #5 #7 #4 AND #5
Scopus	#1 TITLE-ABS-KEY (orthodontic* OR "orthodontic tooth movement” OR "orthodontic Treatment" OR "orthodontic Therapy"). #2 TITLE-ABS-KEY (accelerat* OR rapid* OR short* OR speed* OR fast) #3TITLE-ABS-KEY (“surgical” OR “invasive” OR “minimally invasive”) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #4 TITLE-ABS-KEY (“non-surgical” OR “non-invasive”) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #5 #1 AND #2 #6 #3 AND #5 #7 #4 AND #5
Web of Science	#1TS = (orthodontic OR "orthodontic tooth movement” OR "orthodontic Treatment" OR "orthodontic Therapy"). #2TS = (accelerat* OR rapid* OR short* OR speed* OR fast) #3TS = (surgical OR invasive OR minimally invasive) AND TS = (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #4TS = (non-surgical OR non-invasive AND TS = (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*) #5 #1 AND #2 #6 #3 AND #5 #7 #4 AND #5
Google Scholar	#1 (orthodontic OR "orthodontic tooth movement” OR "orthodontic Treatment" OR "orthodontic Therapy") AND (accelerat* OR rapid* OR short* OR speed* OR fast) AND (surgical OR invasive OR minimally invasive ) AND (combine* OR join* OR associate*) #2 (orthodontic OR "orthodontic tooth movement” OR "orthodontic Treatment" OR "orthodontic Therapy") AND (accelerat* OR rapid* OR short* OR speed* OR fast) AND (non-surgical OR non-invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicat*)
Trip	(orthodontic* OR "orthodontic tooth movement” OR "orthodontic Treatment" OR "orthodontic Therapy") AND (accelerate* OR rapid* OR short* OR speed* OR fast) AND (surgical OR invasive OR minimally invasive) AND (combine* OR join* OR associate*) OR (non-surgical OR non-invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicate*)
OpenGrey (http://www.opengrey.eu/)	#1 acceleration AND tooth movement #2 orthodontic AND acceleration #3 (surgical OR invasive OR minimally invasive ) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicate*) #4 (non-surgical OR non-invasive) AND (combine* OR join* OR associate*) AND (multiple or repeat* or duplicate*)
PQDT OPEN (from proQuest)	#1 acceleration AND tooth movement #2 orthodontic AND acceleration
World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) Search Portal	(orthodontic OR ‘tooth movement’ OR ‘orthodontic tooth movement’) AND (accelerate* OR rapid* OR short* OR speed* OR fast)
ClinicalTrials.gov	(orthodontic OR ‘tooth movement’ OR ‘orthodontic tooth movement’) AND (accelerate* OR rapid* OR short* OR speed* OR fast)