Low-Intensity Pulsed Ultrasound Accelerates Tooth Movement via Activation of the BMP-2 Signaling Pathway

Abstract

The present study was designed to determine the underlying mechanism of low-intensity pulsed ultrasound (LIPUS) induced alveolar bone remodeling and the role of BMP-2 expression in a rat orthodontic tooth movement model. Orthodontic appliances were placed between the homonymy upper first molars and the upper central incisors in rats under general anesthesia, followed by daily 20-min LIPUS or sham LIPUS treatment beginning at day 0. Tooth movement distances and molecular changes were evaluated at each observation point. In vitro and in vivo studies were conducted to detect HGF (Hepatocyte growth factor)/Runx2/BMP-2 signaling pathways and receptor activator of NFκB ligand (RANKL) expression by quantitative real time PCR (qRT-PCR), Western blot and immunohistochemistry. At day 3, LIPUS had no effect on the rat orthodontic tooth movement distance and BMP-2-induced alveolar bone remodeling. However, beginning at day 5 and for the following time points, LIPUS significantly increased orthodontic tooth movement distance and BMP-2 signaling pathway and RANKL expression compared with the control group. The qRT-PCR and Western blot data in vitro and in vivo to study BMP-2 expression were consistent with the immunohistochemistry observations. The present study demonstrates that LIPUS promotes alveolar bone remodeling by stimulating the HGF/Runx2/BMP-2 signaling pathway and RANKL expression in a rat orthodontic tooth movement model, and LIPUS increased BMP-2 expression via Runx2 regulation.

Effect of low-intensity pulsed ultrasound on the activity of osteoclasts: An in vitro study

“…In the other hand, osteoblasts seem to respond differently from cementoblasts after LIPUS application, as previously reported (ElBialy et al, 2011;Xue et al, 2013;Al-Daghreer et al, 2014). In the in vivo experiment performed by Inubushi et al (2013), osteoclasts located along the bone surface were otherwise increased after LIPUS application in one of the experimental groups.…”

“…Histological findings demonstrated increased alveolar bone remodeling due to the elevated number of osteoclast (OC) cells along the bone surfaces of the moved teeth that were subjected to ultrasound application (ElBialy et al, 2011;Inubushi et al, 2013;Xue et al, 2013;Al-Daghreer et al, 2014). The LIPUS-driven increase in the OC number might be attributed to the stimulation of their differentiation as a result of an upregulation of the RANK-L gene expression in osteoblasts (Inubushi et al, 2013;Xue et al, 2013), which generates the most important mediator for osteoclastogenesis (Titorencu, Pruna, Jinga, & Simionescu, 2014).…”

Low-intensity pulsed ultrasound enhances bone morphogenetic protein expression of human mandibular fracture haematoma-derived cells

“…2 Fávaro-Pípi et al found that LIPUS stimulation in rats significantly increased BMP-4 expression on days 7 and 25. 9 10,23 In this study using MHCs extracted from human mandibular fracture sites, only BMP-4 expression was increased in the absence of LIPUS application on days 4 and 8 (Fig. 1).…”

Influence of Low-Intensity Pulsed Ultrasound Stimulation on Expression of Bone-Related Genes in Rat Bone Marrow Cells

“…The present study shows an increase in the expression of Cbfa1/Runx2 and Cox-2 mRNA at an early stage, supporting the previous studies. It was previously reported that LIPUS increased orthodontic tooth movement distance and the BMP-2 signaling pathway in a rat model 17) . 16) .…”