Visualization of mandibular movement relative to the maxilla during mastication in mice: integration of kinematic analysis and reconstruction of a three-dimensional model of the maxillofacial structure

Go Yasuda; Emi Moriuchi; Ryo Hamanaka; Ayumi Fujishita; Tomoko Yoshimi; Kana Yamamoto; Kaori Hayashida; Yoshiyuki Koga; Noriaki Yoshida

doi:10.1186/s12903-021-01879-4

Visualization of mandibular movement relative to the maxilla during mastication in mice: integration of kinematic analysis and reconstruction of a three-dimensional model of the maxillofacial structure

BMC Oral Health. 2021 Oct 14;21(1):527. doi: 10.1186/s12903-021-01879-4.

Authors

Go Yasuda¹, Emi Moriuchi², Ryo Hamanaka¹, Ayumi Fujishita¹, Tomoko Yoshimi², Kana Yamamoto¹, Kaori Hayashida¹, Yoshiyuki Koga², Noriaki Yoshida³

Affiliations

¹ Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan.
² Department of Orthodontics, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan.
³ Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan. nori@nagasaki-u.ac.jp.

Abstract

Background: Mastication is one of the most fundamental functions for the conservation of human life. To clarify the pathogenetic mechanism of various oral dysfunctions, the demand for devices for evaluating stomatognathic function has been increasing. The aim of the present study was to develop a system to reconstruct and visualize 3-dimensional (3D) mandibular movements relative to the maxilla, including dynamic transition of occlusal contacts between the upper and lower dentitions during mastication in mice.

Methods: First, mandibular movements with six degrees of freedom were measured using a motion capture system comprising two high-speed cameras and four reflective markers. Second, 3D models of maxillofacial structure were reconstructed from micro-computed tomography images. Movement trajectories of anatomical landmark points on the mandible were then reproduced by integrating the kinematic data of mandibular movements with the anatomical data of maxillofacial structures. Lastly, 3D surface images of the upper dentition with the surrounding maxillofacial structures were transferred to each of the motion capture images to reproduce mandibular movements relative to the maxilla. We also performed electromyography (EMG) of masticatory muscles associated with mandibular movements.

Results: The developed system could reproduce the 3D movement trajectories of arbitrary points on the mandible, such as incisor, molars and condylar points with high accuracy and could visualize dynamic transitions of occlusal contacts between upper and lower teeth associated with mandibular movements.

Conclusions: The proposed system has potential to elucidate the mechanisms underlying motor coordination of masticatory muscles and to clarify their roles during mastication by taking advantage of the capability to record EMG data synchronously with mandibular movements. Such insights will enhance our understanding of the pathogenesis and diagnosis of oral motor disorders by allowing comparisons between normal mice and genetically modified mice with oral behavioral dysfunctions.

Keywords: EMG; Jaw movements; Mastication; Motion capture; Mouse; Rigid transformation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Biomechanical Phenomena
Mandible / diagnostic imaging
Mastication*
Maxilla* / diagnostic imaging
Mice
Movement
X-Ray Microtomography