Subjective and Functional Outcomes Following TMJ Reconstruction With Custom-made Total Joint Prostheses
Temporomandibular disorder (TMD) is a collective term that embraces a variety of clinical complaints involving the muscles of mastication, the temporomandibular joint (TMJ), or associated orofacial structures.1 TMD exists due to a diverse collection of conditions affecting the muscular system, TMJ or both. 2A common theme seen in TMD patients is pain and dysfunction. The majority of these patients can be managed with conservative/non-surgical therapy because the origin of their discomfort/dysfunction stems from the muscles of mastication rather than from the TMJ. However, pain and dysfunction from certain TMJ pathologies can be treated predictably and successfully with artificial joint reconstruction.
Method.
This retrospective study evaluated treatment records of 30 of 59 end-stage TMJ patients over a span of 4 years. The selected patients matched the adequate inclusion criteria for follow up and/or complete records. Etiologies to end-stage TMJ ranged from trauma, benign pathology, osteoarthritis, reactive arthritis, ankylosis, idiopathic condylar resorption, and connective tissue/autoimmune diseases. 27 had bilateral replacement of joints, 3 had unilateral replacement, 11 of the 30 had a combined maxillary osteotomy with bilateral replacement of joints. CAD/CAM custom-made TMJ total joint prostheses used in this study have been manufactured by TMJ Concepts Inc in Ventura, CA.3
Patients were assessed at presurgery (T1) and at the longest available follow-up (T2). Patients rated themselves in five categories: facial pain/headache, TMJ pain, jaw function, diet and disability. Subjective ratings were made using a scale ranging from 0 to 10: for pain ratings, 0 = no pain to 10 = worst pain imaginable; for jaw function, 0 = normal to 10 = no function; for diet, 0 = no restriction to 10 = liquids only; and for disability, 0 = no disability to 10 = totally disabled.3 Objective functional assessments were performed by measuring the maximum interincisal opening (MIO) and lateral excursion movements at T1 and T2. The relative improvement percentages were determined by comparing the changes as a percentage of the starting values using the following formula: Improvement percentage (IP) = 100 x (T2 - T1)/T1.3
Results.
The average age at surgery was 41.7 years (range 13-67 years), and the average post-surgical follow-up was 16.1 months (range 6 to 37 months). Facial pain/headache decreased 5 points, representing an improvement percentage (IP) of 69.13%; TMJ pain decreased 5 points, IP 74.90%; jaw function improved 5 points, IP 81.25%; diet improved 5 points, IP 80.91%; and disability decreased 4 points, IP 79.89%. MIO increased 73.14%, from 22.83 at T1 to 39.53 mm at T2, but lateral excursion decreased 44.23%, from 3.47 to 1.93mm.
Conclusions.
Our present study demonstrated significant and substantial improvement for facial pain/headaches, TMJ pain, jaw function, diet, disability and MIO following TMJ reconstruction with custom-made total joint prosthesis. We found no difference in groups that had > 2 or more surgeries compared to those with < 2 or no prior surgeries. The documented success and effectiveness of TMJ Concepts to treat pain and dysfunction has been previously documented.3 Our results regarding pain and dysfunction improvements parallel previously reported studies in the literature.
References.
- De Leeuw R. Orofacial pain: guidelines for classification, assessment, and management. 4th edition. Chicago: Quintessence Publ. Co.; 2008.
- Bagheri. S.C. Current Therapy in Oral and Maxillofacial Surgery. 1st Edition.