RANKL and OPG expression: Jiggling force affects root resorption in rats

ABSTRACT Objective: To immunohistochemically investigate the longitudinal changes in root resorption by jiggling force in experimental animal models. Materials and Methods: Fifty-six 12-week-old male Wistar rats were used. The maxillary first molars were alternately moved in the buccal and lingual direction in 28 rats (experimental group) using an experimental appliance to produce jiggling forces of 10 g. In another 28 rats (control group), the maxillary first molars were moved in only the lingual direction with a force of 10 g. After 1, 3, 7, 10, 14, 17, and 21 days, the maxillae were resected and subjected to immunohistochemical analysis. The resorption area was quantified histomorphometrically and the number of odontoclasts on the root surface was counted. Expression of RANKL and OPG was also examined by immunohistochemical staining. Results: The root resorption area and the number of odontoclasts were significantly greater in the experimental group than in controls. Odontoclasts were detected in the r...