Introduction

Recurrent temporomandibular joint dislocation can be a painful, frustrating, and difficult clinical condition for patients. There are many causes of temporomandibular joint (TMJ) hypermobility and dislocation, including intrinsic and extrinsic trauma, connective tissue disorders, psychogenic disorders, and association with specific pharmacologic therapies. Likewise, there is a plethora of surgical and non-surgical therapies that have been described for treatment of chronic TMJ dislocation. These include intraarticular injection of sclerosing agents or autologous blood, plication of capsular TMJ ligaments¹, endoscopic anchoring procedures², surgically induced mechanical impediments to translation (i.e. LeClerc procedure³), lateral pterygoid myotomy⁴, and articular eminectomy (Myrhaug technique)⁵. Each of these interventional modalities attempts to address the problem of TMJ dislocation at different presumed causative etiologies, which include ligamentous hyperlaxity, lateral pterygoid hyperactivity, and/or a prominent articular eminence that (when combined with hypermobility) results in anterior dislocation, but inhibits reduction of the dislocated condyle back into the glenoid fossa. For example, articular eminectomy theoretically reduces an interfering eminence to allow for condylar reduction while still allowing for hyper-translation.  In contrast, sclerosing agents and plication procedures theoretically induce scarring to reduce the laxity of the ligamentous structures and inhibit hypermobility. Though each method addresses the problem in a different manner, they all share a common goal of reducing or eliminating episodes of recurrent dislocation. The use of botulinum toxin (BTX) injections has been previously described as a novel non-surgical treatment modality for TMJ dislocation. This intervention eliminates lateral pterygoid muscle hyperactivity as the causative etiology of TMJ open lock without the associated surgical morbidity of a lateral pterygoid myotomy, which could be considered the surgical equivalent. This course will discuss two cases and review the literature.

Author

Dr. Matthew Mynsberge
Dr. Mynsberge is Chief Resident, Oral and Maxillofacial Surgery at Indiana University School of Medicine and Dentistry.

with Dr. Joseph Heidelman & Dr. Jeffrey Bennett