Elsayed Nagwan, Shimo Tsuyoshi, Harada Fumiya, Takeda Shigehiro, Hiraki Daichi, Abiko Yoshihiro, Nakayama Eiji, Nagayasu Hiroki
Division of Oral and Maxillofacial Surgery, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, 061-0293, Japan; Division of General Dental Sciences I, Department of Oral Rehabilitation, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, 061-0293, Japan.
Division of Reconstructive Surgery for Oral and Maxillofacial Region, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, 061-0293, Japan; Division of General Dental Sciences I, Department of Oral Rehabilitation, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, 061-0293, Japan.
Int J Surg Case Rep. 2021 Jan;78:120-125. doi: 10.1016/j.ijscr.2020.11.150. Epub 2020 Dec 2.
Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a new clinical entity that presents mainly with trismus due to hyperplasia of the masseter aponeurosis and temporalis muscle tendon. However, the etiological factors of this disease are unknown; it is often mistreated as temporomandibular joint disorder (TMD).
We report a 32-year-old female patient complaining of bilateral pain in her jaw and difficulty opening her mouth. She was first diagnosed as TMD and treated with a splint; however, her symptoms did not improve. Clinical examination revealed a square mandible, tenderness in the left and right temporalis muscles and masseter muscles, and tenderness along the anterior border of the masseter muscle. Her maximum mouth-opening was 30 mm. Short TI inversion recovery magnetic resonance imaging showed areas of low intensity at the anterior border of the masseter muscle and around the coronoid process where the temporalis muscle tendon attaches. Consequently, the diagnosis made based on the clinical and radiographic findings was MMTAH. Bilateral coronoidectomy was performed, followed by a rehabilitation program for six months. The maximum opening was maintained at 48 mm two years after the operation.
MMTAH was treated as type 1 TMD until it was recognized as a new disease at the conference for the Japanese Society for Oral and Maxillofacial Surgeons. Since then, many clinicians have become aware of this particular condition, and different treatment modalities have been proposed.
Clinicians should consider MMTAH as a differential diagnosis when the patient's chief complaint is gradually decreasing mouth-opening.
咀嚼肌肌腱 - 腱膜增生（MMTAH）是一种新的临床病症，主要表现为因咬肌腱膜和颞肌肌腱增生导致的牙关紧闭。然而，该病的病因尚不清楚；它常被误诊为颞下颌关节紊乱病（TMD）。
我们报告一名32岁女性患者，主诉双侧颌部疼痛及张口困难。她最初被诊断为TMD并接受了咬合板治疗；然而，她的症状并未改善。临床检查发现下颌呈方形，左右颞肌和咬肌有压痛，咬肌前缘有压痛。她的最大张口度为30毫米。短TI反转恢复磁共振成像显示咬肌前缘及颞肌肌腱附着处的冠状突周围有低信号区。因此，根据临床和影像学检查结果诊断为MMTAH。进行了双侧冠状突切除术，随后进行了为期六个月的康复计划。术后两年最大张口度维持在48毫米。
在日本口腔颌面外科医师协会会议上，MMTAH在被确认为一种新疾病之前一直被视为1型TMD。从那时起，许多临床医生已经意识到这种特殊情况，并提出了不同的治疗方式。
当患者的主要诉求是张口度逐渐减小 时，临床医生应将MMTAH作为鉴别诊断考虑。
