Myrlund 2015.

Study characteristics
Methods	Setting: "Patients recruited from Tromsø, Norway; Public Dental Service Competence Centre of Northern Norway (TkNN) and the University student clinic (UTK). All treatment carried out at TkNN". Design: parallel (2 arms) No. of centres: 1 Study duration: 1 year
Participants	Inclusion criteria: "early mixed dentition with upper central incisors and first molars fully erupted; Angle Class I or Class II occlusion with one or more of the following characteristics: deep bite (≥2/3 overlapping of the incisors), increased overjet ≥5 mm, moderate anterior crowding in combination with an overjet of ≥4 mm". Exclusion criteria: children with Angle Class III malocclusion, crossbites, or retroclined upper incisors Participant sampling: N = 48 selected Group 1 (n = 25): 12 female, 13 male (mean age of 7.7 ± 0.6 years) Group 2 (n = 13): 11 female, 12 male (mean age of 7.7 ± 0.5 years) Sex: 23 female, 25 male Dropouts: 2 (4.2%); 1 from each group
Interventions	Orthodontic intervention: removable appliances and auxiliaries Eruption guidance appliance versus no active treatment (control)
Outcomes	Crowding, lower incisors to mandible, upper incisors to maxilla
Notes	Funding source: “LM‐Instruments Oy, Finland, has supplied the study with free LM activators for the patients”
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Adequate method of randomisaton “For the randomization, each subject was given an identification number. The numbers were written on a closed raffle ticket and put in a hat from where 25 subjects were blindly drawn to the experimental group, the remaining 23 subjects comprising the control group. Drawing was performed by an independent person (HK)."
Allocation concealment (selection bias)	Low risk	Adequate allocation concealment “To avoid any allocation bias, all clinical characteristics and personal data of the patients were concealed at this point.”
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible to blind participants and personnel due to the different interventions used
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Adequate blinding of assessors “Before measuring, all study casts were pooled together and labelled by only numbers to hide any identification of group, patient name, or date of the model from the investigator. Similarly, all cephalograms were blinded before tracing by numbering the X‐rays randomly.”
Incomplete outcome data (attrition bias) All outcomes	Low risk	Low dropout rate “After 1 year, one boy from the treatment group (refused treatment after 6 months) and one girl from the control group (moved) had dropped out, resulting in 24 and 22 subjects in the treatment and control groups, respectively.”
Selective reporting (reporting bias)	Low risk	All outcomes reported
Other bias	Low risk	None identified