ABSTRACT
The objective was to assess how ovariectomy or the administration of artificial female sex hormones affects orthodontic tooth movement (OTM) with fixed appliances. An electronic search of indexed databases was completed without language or time restrictions up to June 2022. The following eligibility criteria were utilized: (i) prospective original controlled clinical studies; (ii) experimental studies on animal models; (iii) subjects undergoing orthodontic therapy with fixed appliances; (iv) clearly defined control groups not undergoing ovariectomy or administration of artificial female sex hormone; and (v) studies with experimental groups receiving the intervention of interest (ovariectomy or artificial female sex hormone administration). Review articles, letters to the editor, case reports, case series, commentaries, cross-sectional studies, retrospective studies, and studies with no well-defined control group were excluded. The quality of the available evidence and the risk of bias within the studies were assessed. All disagreements were resolved via discussion. Seven animal studies were included in the systematic review. Five studies reported that ovariectomy increased the rate of orthodontic tooth movement. Two studies reported that the administration of artificial female sex hormones decreased the rate of orthodontic tooth movement. There is an association between ovariectomies and OTM and between the administration of artificial female sex hormones and OTM. The full extent of the association remains unclear due to the biases that are present and the length of time of orthodontic therapy.
