New York University College of Dentistry, New York, NY, USA.
University of Connecticut School of Dental Medicine, Farmington, CT, USA.
J Oral Rehabil. 2020 Nov;47(11):1319-1329. doi: 10.1111/joor.13087. Epub 2020 Sep 19.
Adverse effects of masticatory muscle injections of Botulinum Toxin (Btx) have been noted in animal and, less dramatically, human studies.
Among women treated in multiple community-based private practices, to compare TMJ bone density and mandibular condylar volume between patients with myofascial TMJD receiving multiple masticatory muscle Btx treatments and similarly diagnosed women not receiving such treatment.
Cohorts consisted of women whose treatment charts indicated a diagnosis of myofascial TMJD: 35 received at least 2 Btx treatment cycles; 44 received none. Bone density at pre-specified regions of interest (ROI) was defined by grey scale values from Cone Beam CT, adjusting for a fixed density phantom included in each scan. Mean bone density and mandibular condyle volume were compared between groups. Dose-response effects were tested within the Btx-exposed group.
The mean density of primary and secondary ROIs was similar between exposure groups, as was condylar volume. Among Btx-exposed women, increasing dose of Btx to the temporalis muscle was inversely proportional to the density of the trabecular area of the mandible body. Many Btx-exposed women received smaller doses of Btx to the masseter muscles than in most TMJD Btx clinical trials.
Masticatory muscle injections of Btx failed to produce clinically significant TMJ bone-related changes. Should Btx receive regulatory approval for treatment of myofascial TMJD, a phase IV study is recommended to evaluate potential adverse effects of Btx on bone and muscle when administered at higher doses and/or for more treatment cycles.
肉毒杆菌毒素（Btx）在咀嚼肌注射中的不良反应已在动物研究中有所报道，在人类研究中则相对不那么显著。
在多个基于社区的私人诊所接受治疗的女性中，比较患有肌筋膜颞下颌关节紊乱（TMJD）并接受多次咀嚼肌 Btx 治疗的患者与未接受此类治疗的具有相同诊断的女性之间的 TMJ 骨密度和下颌髁突体积。
队列由治疗图表显示肌筋膜 TMJD 诊断的女性组成：35 名患者接受了至少 2 个 Btx 治疗周期；44 名患者未接受任何治疗。通过 Cone Beam CT 中的灰度值定义特定感兴趣区域（ROI）的骨密度，对每个扫描中包含的固定密度幻影进行调整。比较两组之间的平均骨密度和下颌髁突体积。在 Btx 暴露组中测试剂量反应效应。
暴露组之间主要和次要 ROI 的平均密度相似，髁突体积也是如此。在接受 Btx 治疗的女性中，颞肌接受的 Btx 剂量增加与下颌骨体的小梁区域密度成反比。许多接受 Btx 治疗的女性接受的咬肌 Btx 剂量比大多数 TMJD Btx 临床试验中的剂量小。
咀嚼肌注射 Btx 未能产生临床上显著的 TMJ 与骨骼相关的变化。如果 Btx 获得治疗肌筋膜 TMJD 的监管批准，建议进行一项 IV 期研究，以评估在更高剂量和/或更多治疗周期下 Btx 对骨骼和肌肉的潜在不良影响。
