Micro-Osteoperforations Induce TNF-α Expression and Accelerate Orthodontic Tooth Movement via TNF-α-Responsive Stromal Cells.

Ria Kinjo,Takahiro Noguchi,Yasuhiko Nara,Jinghan Ma,Itaru Mizoguchi,Kayoko Kanou,Aseel Marahleh,Hideki Kitaura,Saika Ogawa,Fumitoshi Ohori,Adya Pramusita

doi:10.3390/ijms23062968

Ria Kinjo, Takahiro Noguchi + Show 9 more

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https://doi.org/10.3390/ijms23062968

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Abstract

Micro-osteoperforations (MOPs) have been reported to accelerate orthodontic tooth movement (OTM), and tumor necrosis factor (TNF)-α has been reported to play a crucial role in OTM. In this report, the influence of MOPs during OTM was analyzed. We evaluated the expression of TNF-α with and without MOPs by RT-PCR analysis. A Ni-Ti closed coil spring was fixed between the maxillary left first molar and the incisors as an OTM mouse model to move the first molar in the mesial direction. MOPs were prepared on the lingual side and mesial side of the upper first molars. Furthermore, to investigate the target cell of TNF-α for osteoclast formation during OTM with MOPs in vivo, we created four types of chimeric mice in which bone marrow of wild-type (WT) or TNF receptor 1- and 2-deficient mice (KO) was transplanted into lethally irradiated WT or KO mice. The results showed that MOPs increased TNF-α expression, the distance of tooth movement and osteoclast formation significantly. Furthermore, mice with TNF-α-responsive stromal cells showed a significant increase in tooth movement and number of osteoclasts by MOPs. We conclude that MOPs increase TNF-α expression, and tooth movement is dependent on TNF-α-responsive stromal cells.

Highlights

We found that tumor necrosis factor (TNF)-α plays important roles in an orthodontic tooth movement (OTM) mouse model by using both TNF receptor 1- and TNF receptor 2-deficient (KO)
The results of this study suggested that the response of stromal cells to TNF-α is a crucial factor for osteoclast formation and bone resorption in OTM [37]
The findings showed that the response of stromal cells to TNF-α is a crucial factor for osteoclast formation and bone resorption in OTM

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. A key concern for orthodontics is the lengthy duration of orthodontic treatment. Shortening the duration of orthodontic treatment is an active research area. Many methods have been tested to accelerate tooth movement, including biological, mechanical, physical and surgical approaches [1]. Surgical procedures are the most consistent and achieve the desired results. Surgical methods that accelerate orthodontic tooth movement are based on the regional acceleratory phenomenon (RAP), which involves an enhanced remodeling process in response to harmful stimuli [2]

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