Experimental validation of sleep regulatory factors involved in the diurnal variation of sleep bruxism

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K24069
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0907:Oral science and related fields
• Research Institution: Osaka University
• Principal Investigator: haraki shingo 大阪大学, 歯学研究科, 招へい教員 (70845982)
• Project Period (FY): 2019-08-30 – 2022-03-31
• Keywords: 睡眠時ブラキシズム

Outline of Final Research Achievements

In this study, polysomnography (PSG) testing was performed on two consecutive nights in a sleep laboratory in young healthy adults. The severity of sleep bruxism (SB) was then diagnosed, and the influence of diurnal variation on the SB diagnosis was examined. Subsequently, in the severe SB group, we examined the relationship between variability of masticatory muscle activity and sleep. The results showed that rhythmic masticatory muscle activity (RMMA), a diagnostic marker of SB, decreased on the first night of PSG testing due to the first night effect, and that the diurnal variability of RMMA was greater in the severe SB group. In addition, the variability was influenced by the changes of arousal occurrence related to ultradian rhythms, rather than the increase of arousal-related variables.

Free Research Field

睡眠歯科

Academic Significance and Societal Importance of the Research Achievements

歯科の臨床現場ではすでに様々な治療方法が提案されているが、睡眠時ブラキシズムの診断方法は確立されておらず、病態生理は不明である。本研究では、第一夜効果による睡眠の質の低下がRMMAの発生を誘発するものでないことを明らかにした点が学術的に意義がある。また睡眠時ブラキシズムの日間変動の動態に関する生理学的機序を明らかにすることは、睡眠時ブラキシズムの診断や治療の評価において、科学的アプローチを明確にする一助となったと考えている。