Biomechanical stress regulates mammalian tooth replacement.

Xiaoshan Wu,Songlin Wang

doi:10.15698/cst2020.03.215

Abstract

Cyclical renewal of integumentary organs, including hair, feathers, and teeth occurs throughout an organism's lifetime. Transition from the resting to the initiation stage is critical for each cycle, but the mechanism remains largely unknown. Humans have two sets of dentitions—deciduous and permanent—and tooth replacement occurs only once. Prior to eruption of the permanent tooth (PT), the successional dental lamina (SDL) of the PT can be detected as early as the embryonic stage, even though it then takes about 6–12 years for the SDL to develop to late bell stage. Little is known about the mechanism by which resting SDL transitions into the initiation stage inside the mandible. As a large mammal, the miniature pig, which is also a diphyodont, was a suitable model for our recent study (EMBO J (2020)39: e102374). Using this model, we found that the SDL of PT did not begin the transition into the bud stage until the deciduous tooth (DT) began to erupt.

Highlights

The deciduous tooth (DT) eruption released a biomechanical stress of about 3-20 kPa inside the mandible
We found that the successional dental lamina (SDL) of permanent tooth (PT) did not begin the transition into the bud stage until the deciduous tooth (DT) began to erupt
Our study identified biomechanical stress-associated Wnt modulation as an initiator of organ renewal, and this finding could be valuable for future study of integumentary organ regeneration

Summary

Introduction

The DT eruption released a biomechanical stress of about 3-20 kPa inside the mandible. * Corresponding Author: Songlin Wang, Tel:+86-010-57099478; E-mail: slwang@ccmu.edu.cn Transition from the resting to the initiation stage is critical for each cycle, but the mechanism remains largely unknown. Little is known about the mechanism by which resting SDL transitions into the initiation stage inside the mandible.

Results

Conclusion