Revision temporomandibular joint arthroplasty for the treatment of acquired metal allergy and review of the literature.

The purpose of this study was to examine the outcomes of patients who received revision temporomandibular joint (TMJ) arthroplasty for the treatment of acquired metal allergy. It was hypothesized that subjects would have significant improvements in pain, swelling, and function. Patients who underwent TMJ revision due to nickel allergy were identified retrospectively. Outcomes documented included the presence or absence of facial erythema and facial swelling. Maximum incisal opening was also measured. Additional outcomes collected included age at initial surgery, initial TMJ device type, presenting symptoms, and TMJ device used for surgical revision. Four patients were identified with a nickel allergy to their TMJ prosthesis (containing nickel). All subjects experienced pain and swelling as their primary symptoms prior to the revision, with two subjects showing dermatological symptoms of overlying erythema. The four female subjects underwent exchange of their previously implanted prosthesis with a titanium alloy prosthesis. Postoperatively, all subjects showed improvements in pain score, resolution of swelling and erythema, and improvements in maximum incisal opening. This small case series suggests that revision TMJ arthroplasty with a titanium alloy prosthesis is a potential treatment for acquired metal allergy from traditional TMJ prosthesis implantation.

Experimental Methods to Inform Diagnostic Approaches for Painful TMJ Osteoarthritis.

Temporomandibular joint (TMJ) osteoarthritis (OA) is a degenerative disease of the joint that can produce persistent orofacial pain as well as functional and structural changes to its bone, cartilage, and ligaments. Despite advances in the clinical utility and reliability of the Diagnostic Criteria for Temporomandibular Disorders, clinical tools inadequately predict which patients will develop chronic TMJ pain and degeneration, limiting clinical management. The challenges of managing and treating TMJ OA are due, in part, to a limited understanding of the mechanisms contributing to the development and maintenance of TMJ pain. OA is initiated by multiple factors, including injury, aging, abnormal joint mechanics, and atypical joint shape, which can produce microtrauma, remodeling of joint tissues, and synovial inflammation. TMJ microtrauma and remodeling can increase expression of cytokines, chemokines, and catabolic factors that damage synovial tissues and can activate free nerve endings in the joint. Although studies have separately investigated inflammation-driven orofacial pain, acute activity of the trigeminal nerve, or TMJ tissue degeneration and/or damage, the temporal mechanistic factors leading to chronic TMJ pain are undefined. Limited understanding of the interaction between degeneration, intra-articular chemical factors, and pain has further restricted the development of targeted, disease-modifying drugs to help patients avoid long-term pain and invasive procedures, like TMJ replacement. A range of animal models captures features of intra-articular inflammation, joint overloading, and tissue damage. Although those models traditionally measure peripheral sensitivity as a surrogate for pain, recent studies recognize the brain's role in integrating, modulating, and interpreting nociceptive inputs in the TMJ, particularly in light of psychosocial influences on TMJ pain. The articular and neural contributors to TMJ pain, imaging modalities with clinical potential to identify TMJ OA early, and future directions for clinical management of TMJ OA are reviewed in the context of evidence in the field.

Post-surgical neuromas in patients with total alloplastic temporomandibular joint reconstruction: a retrospective case series.

This study evaluated pain scores and maximal incisal opening (MIO) in patients with total alloplastic temporomandibular joints found to have post-surgical neuromas following revision arthroplasty, compared with patients who underwent revision arthroplasty without neuromas. 19 cases were reviewed of which 11 had neuromas excised. Data were available for 8 cases in the immediate postoperative period and 7 cases had follow-up data. 8 patients had revision arthroplasty with excision of scar tissue (7 with postoperative, 4 with long-term data). Follow-up ranged from 2 months to 5.9 years (mean 1.2 years). 6 of 8 patients obtained clinically significant pain reduction in the immediate postoperative period when their neuromas were excised, compared with 3 of 7 patients without neuromas. On long-term follow-up, 3 of 7 patients in the neuroma group had clinically significant pain reduction, 3 reported lower pain scores, 1 had no pain change. No patients had increased pain. 1 of 4 patients in the scar revision group had clinically significant pain reduction, 2 had no change, 1 reported increased pain. Mean MIO was 23 mm preoperative and 28 mm postoperative in patients with neuromas, compared with 27.75 mm and 31.25 mm, respectively, in patients without neuromas.