Vibration paradox in orthodontics: Anabolic and catabolic effects

Abstract

Vibration in the form of High Frequency Acceleration (HFA) is anabolic on the craniofacial skeleton in the absence of inflammation. Orthodontic forces trigger an inflammation-dependent catabolic cascade that is crucial for tooth movement. It is unknown what effect HFA has on alveolar bone if applied during orthodontic treatment. The objectives of this study are to examine the effect of HFA on the rate of tooth movement and alveolar bone, and determine the mechanism by which HFA affects tooth movement. Adult Sprague Dawley rats were divided to control, orthodontic force alone (OTM), and different experimental groups that received the same orthodontic forces and different HFA regimens. Orthodontic tooth movement was assessed when HFA parameters, frequency, acceleration, duration of exposure, and direct or indirect application were varied. We found that HFA treatment significantly enhanced the inflammation-dependent catabolic cascade during orthodontic tooth movement. HFA treatment increased inflammatory mediators and osteoclastogenesis, and decreased alveolar bone density during orthodontic tooth movement. Each of the HFA variables produced significant changes in the rate of tooth movement and the effect was PDL-dependent. This is the first report that HFA enhances inflammation-dependent catabolic cascades in bone. The clinical implications of our study are highly significant, as HFA can be utilized to enhance the rate of orthodontic tooth movement during the catabolic phase of treatment and subsequently be utilized to enhance retention during the anabolic remodeling phase after orthodontic forces are removed.

Effects of two frequencies of vibration on the maxillary canine distalization rate and RANKL and OPG secretion: A randomized controlled trial

“…Neither 30 or 60 Hz vibratory stimulus accelerated the rate of canine distalization nor increased inflammatory cytokine secretion in this study. The insignificant effects of 30 Hz vibration are in accordance with previous clinical studies, but in contrast to some animal studies . Low‐frequency vibratory stimulus (5‐20 Hz) did not exert an acceleratory effect in a mouse study .…”

“…Low‐frequency vibratory stimulus (5‐20 Hz) did not exert an acceleratory effect in a mouse study . However, 30, 60 and 120 Hz vibration significantly accelerated molar movement (by 1.45‐, 2.1‐ and 2.4‐fold, respectively) compared to controls in a rat study, and 125 Hz vibration significantly increased canine distalization and IL‐1β secretion in a clinical trial . These findings indicate vibration exerts a dose‐response effect on orthodontic tooth movement, and that 30 and 60 Hz vibration may have no influence or may be inadequate to stimulate additional release of inflammatory cytokines from PDL and alveolar bone cells compared to orthodontic force only.…”

“…The insignificant effects of 30 Hz vibration are in accordance with previous clinical studies, 11,12 but in contrast to some animal studies. 6,7 Low-frequency vibratory stimulus (5-20 Hz) did not exert an acceleratory effect in a mouse study. 9 However, 30, 60 and 120 Hz vibration significantly accelerated molar movement (by 1.45-, 2.1-and 2.4-fold, respectively) compared to controls in a rat study, 6…”

“…6,7 Low-frequency vibratory stimulus (5-20 Hz) did not exert an acceleratory effect in a mouse study. 9 However, 30, 60 and 120 Hz vibration significantly accelerated molar movement (by 1.45-, 2.1-and 2.4-fold, respectively) compared to controls in a rat study, 6…”

“…Vibratory stimulus has been proposed as an approach to accelerate tooth movement . In vitro studies suggest vibration may accelerate tooth movement by inducing inflammatory mediators, though animal studies have reported conflicting results and vibration did not accelerate irregularity index improvements in clinical studies . Nevertheless, the ability of vibration to increase the distance of tooth movement is controversial .…”