Quantitative evaluation of masseter muscle stiffness in patients with temporomandibular disorders by shear wave elastography

• Project/Area Number: 25861838
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Niigata University
• Principal Investigator: TAKASHIMA Makiko 新潟大学, 医歯学総合病院, 医員 (10547590)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000); Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2014: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2013: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 顎関節症 / 筋筋膜痛 / せん断弾性波 / エラストグラフィ / 超音波診断装置 / 筋痛障害 / せん断弾性波伝搬速度 / 咀嚼筋障害 / 筋電図測定

Outline of Final Research Achievements

We aimed to quantify masseter muscle stiffness in patients with masticatory myofascial pain. Masseter muscle stiffness was measured by　shear wave elastography, which expresses stiffness as shear wave velocity (Vs). Muscle stiffness was 1.96 m/s (4.18 kPa) in 13 patients in Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) group Ia, 2.00 m/s (4.34 kPa) in 13 patients in RDC/TMD group Ib and 1.27 m/s (1.75 kPa) in 24 control subjects. Vs was significantly greater in groups Ia and Ib than in control (Steel&Dwass test, p < 0.05). Characteristic pain intensity (CPI) became clear as an independent factor impacting Vs (partial regression coefficient = 0.625; multiple regression analysis, p < 0.05). Masseter muscles stiffness correlated with CPI (Spearman’s rank order test, p < 0.05) and was about two-fold greater in groups Ia and Ib than in healthy subjects.

Research Products

• [Presentation] 咀嚼筋痛障害患者の終日咬筋の筋活動分析 (2014)
  • Author(s): 高嶋真樹子, 河村篤志, 白井友恵, 荒井良明, 高木律男
  • Organizer: 一般社団法人日本顎関節学会総会・学術大会
  • Place of Presentation: 九州大学医学部百年講堂（福岡）
  • Year and Date: 2014-07-19 – 2014-07-20