The effect of low intensity pulsed ultrasound in a 3D ex vivo orthodontic model

Objectives: This study investigated the effects of low intensity pulsed ultrasound (LIPUS) on dentoalveolar structures during orthodontic force application using a novel organ culture system. Methods: Mandibles were dissected from 28-day-old male Sprague Dawley rats, sliced into 1.5 mm and cultured at 37 degrees C and 5% CO(2), prior to application of a 50 g force to each mandible slice. Slices were randomly divided into three groups of control, 5 and 10 min LIPUS application and cultured for five days before histological and histomorphometrical analysis. Results: Cementum and predentine thickness and subodontoblast and periodontal ligament cell counts were increased in the ultrasound groups, with increases statistically significant in the 10 min treated groups. Odontoblasts remained viable during LIPUS exposure and osteoclast activity was increased by LIPUS. Conclusions: LIPUS may influence remodelling of the dentine-pulp complex and associated tissues during orthodontic force application ex vivo. (C) 2011 Elsevier Ltd. All rights reserved.