Table 1. .

Eligibility Criteria Considered for the Systematic Review

Domain	Inclusion Criteria	Exclusion Criteria
Participants	▪ Animal subjects subjected to relapse without any form of retention, immediately following orthodontic tooth movement	▪ Animal subjects with any form of retention before or during the period of relapse
Interventions	▪ Local or systemic administration of pharmacological agents during the period of relapse (excepting those substances that are administered once for a long period of time, such as the bisphosphonates)	▪ Administration of substances that are experimental or not prescribed to humans ▪ Simultaneous administration of substances not considered in the present review ▪ Simultaneous use of other types of interventions intended to affect OR
Comparisons	▪ Placebo intervention or no intervention	▪ Studies with only baseline controls not subjected to OTM or control group with retention appliance
Outcomes	▪ Quantitative data regarding tooth movement relapse following OTM (rate of relapse, percentage relapse, amount of relapse, etc.)	▪ Qualitative assessments regarding tooth movement relapse ▪ Inadequate definition of outcomes
Study design	▪ Experimental prospective controlled studies	▪ Noncomparative studies (case reports and case series) ▪ Systematic reviews and meta-analyses ▪ In vitro or ex vivo studies ▪ Opinions and editorials