Objective: The objective was to systematically-review the effect of statin drugs on orthodontic-tooth-movement (OTM). Design: The focused-question was “Does statin therapy affect OTM?” PubMed, Ovid Medline, Cochrane Library, Scopus, EMBASE and Web of Science databases were searched without time and language restrictions using different key words. Studies assessing the effect of adjunctive statin administration on OTM compared with orthodontic treatment alone were included. The search was performed up to and including December 2018. Data regarding the study design/grouping, subjects, age/gender, duration of follow-up, outcome variables and parameters related to OTM and statins administration were evaluated. Results: Nine studies (1 clinical and 8 studies performed in animal-models) were included. Six studies used Simvastatin, whereas three studies used Atorvastatin. Six experimental studies and one clinical study reported reduction in OTM upon statin administration. Two experimental studies reported no effect of statin administration on OTM. In 90 % of the studies, the risk-of-bias was high. Conclusion: Based upon the high risk-of-bias and methodological inconsistencies among the included studies, the influence of statin delivery on OTM remains debatable.