Chen Chen-Kun, Tang Yueh-Bih
Taipei, Taiwan From the Division of Plastic Surgery, Department of Surgery, National Taiwan University Hospital.
Plast Reconstr Surg. 2007 Dec;120(7):1859-1864. doi: 10.1097/01.prs.0000287136.22709.77.
Paralysis of the marginal mandibular branch of the facial nerve is frequently seen in patients with oromandibular reconstructions or facial palsy. However, deformities caused by overpulling of the depressor muscles of the contralateral lower lip without being antagonized by the diseased counterpart is often quite conspicuous. Depressor myectomy of the contralateral lower lip therefore provides a method for correcting the dynamic deformity.
Seventy-six patients with paralysis of the marginal mandibular branch of the facial nerve were treated with either surgical depressor myectomy of the lower lip (25 patients), depressor myectomy with subsequent botulinum toxin injection (eight patients), or only chemical depressor myectomy with botulinum toxin injections (43 patients).
Good to fair results were always achieved, with near balance of the lower lip during mouth opening and in facial expressions. Surgical myectomy may still result in recurrence in eight patients (24 percent), which will necessitate further treatment with botulinum toxin injections.
Using myectomy for paralysis of the marginal mandibular branch of the facial nerve can be an effective treatment for this significant deformity. Chemical myectomy with botulinum toxin injection is a safe and convenient mode of treatment; however, the disadvantage is that it needs repeated injections and costs more.
面神经下颌缘支麻痹在口腔颌面部重建或面瘫患者中较为常见。然而，由于患侧下唇降肌失去拮抗作用，对侧下唇降肌过度牵拉所导致的畸形往往十分明显。因此，对侧下唇降肌切除术为矫正这种动态畸形提供了一种方法。
76例面神经下颌缘支麻痹患者接受了以下治疗：下唇降肌手术切除（25例）、下唇降肌切除后注射肉毒杆菌毒素（8例）或仅注射肉毒杆菌毒素进行化学性降肌切除（43例）。
治疗效果良好至中等，张口和面部表情时下唇基本平衡。手术切除降肌后仍有8例（24%）复发，需进一步注射肉毒杆菌毒素治疗。
对于面神经下颌缘支麻痹，采用降肌切除术是治疗这种严重畸形的有效方法。注射肉毒杆菌毒素进行化学性降肌切除是一种安全、便捷的治疗方式；然而，缺点是需要重复注射且费用较高。
