Longitudinal assessment of large-scale MRI data for elucidation of pathological progression mechanism of temporomandibular disorders

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K17165
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Osaka University
• Principal Investigator: Takaoka Ryota 大阪大学, 歯学部附属病院, 医員 (20733968)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 顎関節症 / 変形性顎関節症 / 関節円板側方転位 / Subchondral cyst / MRI

Outline of Final Research Achievements

The present study longitudinally investigated subchondral cyst (SC) in temporomandibular joint (TMJ). Based on the result, SCs tended to form in anterosuperior and central parts of the condyle where mechanical loading was likely to be applied. SCs were strongly associated with abnormal joint disc position. In addition, two-thirds of SCs resolved over time, accompanying the resorption and deformation of the condyle and eminence.
The present study also had observed sideways disc displacement in 23 TMJs for 4-9 years by using MRI. This longitudinal study revealed that in some TMJs, the degree of sideways displacement changed, but there was no case in which the sideway displacement changed to the anterior disc displacement

Free Research Field

顎関節症

Academic Significance and Societal Importance of the Research Achievements

Subchondral cyst(SC)は変形性顎関節症と診断される決定的な画像所見であるにもかかわらずその病態は明らかになっていない．本研究において顎関節円板転位がSCの発生条件の一つであることが明らかとなり，またSCを有する患者は保存療法のみでも安定した経過を辿ることが明らかとなった．また，関節円板側方転位の病態も明らかではなかったが，本縦断研究により，円板側方転位は円板前方転位とは異なるメカニズムで発症し，独自の経過を辿る可能性が示唆された．