title: Strontium ranelate improved tooth anchorage and reduced root resorption in orthodontic treatment of rats.
abstract: The anchorage mechanisms currently used in orthodontic treatment have various disadvantages. The objective of this study was to determine the applicability of the osteoporosis medication strontium ranelate in pharmacologically induced orthodontic tooth anchorage. In 48 male Wistar rats, a constant orthodontic force of 0.25 N was reciprocally applied to the upper first molar and the incisors by means of a Sentalloy(®) closed coil spring for two to four weeks. 50% of the animals received strontium ranelate at a daily oral dosage of 900 mg per kilogramme of body weight. Bioavailability was determined by blood analyses. The extent of tooth movement was measured both optometrically and cephalometrically (CBCT). Relative alveolar gene expression of osteoclastic markers and OPG-RANKL was assessed by qRT-PCR and root resorption area and osteoclastic activity were determined in TRAP-stained histologic sections of the alveolar process. Compared to controls, the animals treated with strontium ranelate showed up to 40% less tooth movement after four weeks of orthodontic treatment. Gene expression and histologic analyses showed significantly less osteoclastic activity and a significantly smaller root resorption area. Blood analyses confirmed sufficient bioavailability of strontium ranelate. Because of its pharmacologic effects on bone metabolism, strontium ranelate significantly reduced tooth movement and root resorption in orthodontic treatment of rats. Strontium ranelate may be a viable agent for inducing tooth anchorage and reducing undesired root resorption in orthodontic treatment. Patients under medication of strontium ranelate have to expect prolonged orthodontic treatment times.
authors.affiliation: Department of Orthodontics, University Hospital of Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany. Electronic address: christian.kirschneck@ukr.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Kirschneck
authors.affiliation: Department of Orthodontics, University of Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany. Electronic address: michael.wolf@ukb.uni-bonn.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Wolf
authors.affiliation: Department of Orthodontics, University Hospital of Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany. Electronic address: claudia.reicheneder@ukr.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Reicheneder
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany. Electronic address: ulrich.wahlmann@ukr.de.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wahlmann
authors.affiliation: Department of Orthodontics, University Hospital of Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany. Electronic address: peter.proff@ukr.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Proff
authors.affiliation: Department of Orthodontics, University Hospital of Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany. Electronic address: piero.roemer@ukr.de.
authors.forename: Piero
authors.initials: P
authors.lastname: Roemer
mesh_terms: D000818:Animals; D008297:Male; D008963:Molar / Q000187:drug effects; D010010:Osteoclasts / Q000187:drug effects; D053245:RANK Ligand / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012391:Root Resorption / Q000188:drug therapy*; D013876:Thiophenes / Q000494:pharmacology*; D014087:Tooth Movement Techniques / Q000379:methods
chemical_list: D053245:RANK Ligand; D013876:Thiophenes; C081587:strontium ranelate
keywords: Cone-beam computed tomography; Orthodontic tooth movement; Quantitative real time PCR; Root resorption; Strontium ranelate; Strontium ranelate (PubChem CID: 6918182); Tooth anchorage