Study Random selection
in the population 		Definition of inclusion
and exclusion criteria 		Report of losses
to follow-up 		Validated
measurements 		Statistical
analysis 		Risk of
bias
Froum et al. [16] Yes Yes No Yes No High
Tarnow et al. [17] Yes Yes No Yes No High
Tawil et al. [24] Yes Yes No Yes No High
Wallace et al. [25] No Yes No Yes No High
Choi et al. [26] Yes Yes Yes Yes Yes Low
Barone et al. [27] Yes Yes Yes Yes Yes Low
García-Denche et al. [28] Yes Yes No Yes Yes Moderate