Influence of corticosteroid therapy on orthodontic tooth movement: A narrative review of studies in animal-models.

The aim was to assess the influence of corticosteroid therapy (CST) on orthodontic tooth movement (OTM). A narrative review of studies performed in animal models. Indexed databases were searched up to and including May 2018 to address the following focused question: "Does CST affect OTM?" The following eligibility criteria were imposed: (a) original studies; (b) presence of a control group (OTM without CST); (c) intervention: effect of CST on OTM; and (d) statistical analysis. Quality assessment was performed using the Animal Research Reporting In Vivo Experiment (ARRIVE) guidelines. Case series, case reports, commentaries, historic reviews and letters to the Editor were excluded. Ten studies performed on animal models were included. The experimental duration ranged between 3 and 49 days. Two studies reported that CST decreases the magnitude of OTM, two studies showed no significant influence of CST on OTM, and two studies found that CST increases OTM. Two studies reported CST significantly decreases bone density and increases bone resorption during OTM. In one study, CST significantly decreased orthodontically induced root resorption. The minimum, median and highest scores (out of 20) based on ARRIVE guidelines were 7, 15.5 and 18, respectively. The influence of CST on OTM in animal models remains debatable.