title: An investigation on the simultaneously recorded occlusion contact and surface electromyographic activity for patients with unilateral temporomandibular disorders pain.
abstract: The present study examined if unilateral pain from temporomandibular disorders (TMD) was associated with the occlusion contacts and surface electromyographic (SEMG) activities of jaw-closing muscles. Eleven patients with unilateral TMD pain and 20 healthy volunteers who all had Angle's Class-I occlusions were enrolled. The numbers and load distributions of the occlusion contacts and the SEMG activities of the anterior temporalis (TA) muscles and masseters muscles (MM) during maximal voluntary clenching (MVC) in the centric and eccentric positions were simultaneously recorded on both sides. The pain was not associated with occlusal contact numbers or load distributions. The SEMG activities of the pain-side TA and bilateral MM were lower during centric MVC compared with controls. The SEMG activities of the non-pain-side TA and the normalized SEMG activities of the bilateral TAs and MMs were higher during protrusive MVC (p<0.05). During pain-side MVC, the normalized SEMG activities of the working-side MM and balancing-side TA were higher than those of the controls. In conclusion, the TMD pain side was not associated with the occlusal contacts, but the patients with TMD had TA and MM SEMG activities during different tasks that differed from controls and that did not seem related to the pain side.
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
authors.forename: Bao-Yong
authors.initials: BY
authors.lastname: Li
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
authors.forename: Shao-Xiong
authors.initials: SX
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology, School of Stomatology, The Fourth Military Medical University, Xi'an, China. Electronic address: mqwang@fmmu.edu.cn.
authors.forename: Mei-Qing
authors.initials: MQ
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D003766:Dental Occlusion; D004576:Electromyography; D005260:Female; D006801:Humans; D008406:Masseter Muscle / Q000502:physiology / Q000503:physiopathology*; D009119:Muscle Contraction; D013703:Temporal Muscle / Q000502:physiology / Q000503:physiopathology*; D013706:Temporomandibular Joint Dysfunction Syndrome / Q000503:physiopathology*
keywords: Bite force; Electromyography; Jaw-closing muscle; Occlusal contact; T-Scan