Temporomandibular joint reconstruction with total alloplastic joint replacement

Abstract

This paper is a preliminary paper which presents the early findings of an ongoing prospective trial on the use of the TMJ Concepts and Biomet Lorenz total joint replacement systems for the reconstruction of the temporomandibular joint (TMJ).Total alloplastic replacement of the TMJ has become a viable option for many people who suffer from TMJ disease where surgical reconstruction is indicated. Degenerative joint diseases such as osteoarthritis, rheumatoid arthritis, psoriatic arthritis, TMJ ankylosis, malunited condylar fractures and tumours can be successfully treated using this technique.There are a number of TMJ prostheses available. Two of the joint replacement products, which have been found to be most reliable and have FDA approval in the United States, are the TMJ Concepts system and the Biomet Lorenz system, and for this reason they are being investigated in this study.This study presents the findings of seven patients with a total of 12 joint replacements using either the TMJ Concepts system or the Biomet Lorenz joint system. Two patients (3 joints) had the TMJ Concepts system and five patients (9 joints) had the Biomet Lorenz system.Although still early, the results were generally pleasing, with the longest replacement having been in position for three years and the most recent six months. The average postoperative mouth opening was 29.7 mm (range 25-35 mm) with an average pain score of 1.7 (range 0-3, minimum score of 0 and maximum 10). Complications were minimal and related to sensory disturbance to the lip in one patient and joint dislocation in two patients.

Adaptability of stock TMJ prosthesis to joints that were previously treated with custom joint prosthesis

“…In patients whose medical conditions and/or difficulty secondary to c-spine instability places them at a risk for general anaesthesia, a stock prosthesis remains a viable option. The anatomical fit of the components enhances the effectiveness and long-term stability of total alloplastic TMJ devices 5,12,13 . Opponents of the stock joint system state that in general, stock joints have an inferior fit, but the narrow or offset mandibular components of the system allow for unusual anatomy.…”

“…When a component of the joint is extensively damaged, degenerated or lost, replacement with an alloplastic implant is the ideal approach to achieve functional and symptomatic improvement in the adult patient 3,4,14 . Total TMJ replacement as a unit has been shown to be superior to partial TMJ replacement 5 . The two systems used most often are the TMJ Concepts 1 7,10,16 .…”

Alloplastic total temporomandibular joint replacement using stock prosthesis: a one-year follow-up report of two cases

“…In the case of extensive congenital bone defect, customized prosthesis is likely to be more desirable than stock prosthesis and is available with an efficient design for posterior stop after orthognathic surgery13. Meanwhile, some literatures suggested that the titanium backing of fossa component osseointegrated with the temporal bone may be unfavorable for re-operation14.…”

Interpositional Arthroplasty in the Treatment of Temporomandibular Joint Ankylosis: A Review of Literature

“…The authors obtained excellent long-term postoperative results in 6 patients. Jones [28] also used alloplastic material for reconstruction of TMJ. The results of this study show an increase in mandibular opening from the preoperative average of 14.4mm to an average opening of 29.7mm postoperatively.…”

“…This situation may be the trigger for unfavorable results with total reconstructions [28]. Metal-on-metal joints also lead to considerably more cobalt and chromium in the body and the long-term effects of this accumulation are not known, therefore it may lead to an increase in cell toxicity, hypersensitivity and carcinogenesis [28] The occurrence of metal hypersensitivity is significantly greater with the metal-onmetal joints. The wear particles from these metals have been shown to be a problem [28,29].…”