Update on the vitek partial and total temporomandibular joint systems

Area of Science:

• Oral and Maxillofacial Surgery
• Biomaterials Science
• Orthopedic Surgery

Background:

• Temporomandibular joint (TMJ) disorders often necessitate surgical intervention.
• Previous generations of TMJ implants, such as VK I, have demonstrated variable long-term success rates.
• Understanding the comparative performance of different TMJ prostheses is crucial for clinical decision-making.

Purpose of the Study:

• To compare the long-term success rates and clinical outcomes of VK I and VK II temporomandibular joint prostheses.
• To identify the primary failure modes associated with VK I implants.
• To evaluate the impact of prior surgical history on total TMJ replacement outcomes.

Main Methods:

• A retrospective recall study involving 262 patients who received VK I (N=138) or VK II (N=124) partial or total temporomandibular joint implants between 1982 and 1990.
• Analysis of cumulative success rates up to 10 years for VK I and up to 6 years for VK II.
• Assessment of patient-reported outcomes including pain relief, interincisal opening, diet, and overall satisfaction.
• Evaluation of implant material failure and the efficacy of secondary procedures like rib grafts.

Main Results:

• VK II total joints exhibited a cumulative success rate of approximately 80% up to 6 years, significantly higher than VK I's approximately 20% up to 10 years.
• Material wear of the Teflon fluorinated ethylene propylene polymer surface was the primary cause of VK I failure; VK II prostheses showed no material failures.
• Patients reported better pain relief, increased interincisal opening, improved diet, and greater satisfaction with VK II implants.
• Previous TMJ surgery negatively impacted the success of both VK I and VK II total joint placement; rib grafts were not effective after prosthesis removal in multiply operated patients.

Conclusions:

• The VK II temporomandibular joint prosthesis demonstrates superior long-term success rates and improved patient-reported outcomes compared to the VK I prosthesis.
• Material failure, specifically wear of the polymer surface, is a significant limitation of the VK I implant.
• Total temporomandibular joint replacement should be reserved for cases where conservative or alternative surgical methods have failed, and vigilant monitoring of implants is essential.