Cellular and Molecular Biology, Physiology and Biotechnology Branch
Division of Basic and Translational Sciences
OBJECTIVE
We are seeking Concept Clearance for a Request for Proposal (RFP). The goals of this initiative are:
- to establish and maintain a national registry of patients who have had or will receive TMJ implants;
- to collect medical information on the enrollees from their health care provider records and interviews in order to document the state of the TMJ in patients before and after implant removal;
- to retrieve and maintain a collection of TMJ implants from these patients to correlate the condition of a retrieved implant with the medical state of the patient; and
- to develop a process to make TMJ implants available to biomedical researchers studying medical implant performance.
In order to accomplish these objectives, the registry will consist of individuals who have had or currently have a partial or total TMJ implant and who are willing to participate in biomedical studies of the natural history of the consequences of this procedure. To date, there has not been a systematic investigation of the natural history of any TMJ implant other than reports of failures. Since long term data on the behavior of implants and the host response are essential to determining the feasibility of TMJ implants, this registry will serve as a national resource for the biomedical research community engaged in the study of the natural history of patients with TMJ implants, and in the improvement of the performance of this form of medical implant.
BACKGROUND
About 3-5% of Americans are affected by TMD. An estimated 100,000 patients (one patient may have received multiple devices, left, right/ 1st, 2nd etc) have received TMJ devices (Stan Mendenhall, Orthopedic Networks, Ann Arbor, MI). Although long-term data on the behavior of implanted devices and host responses are essential inputs to the development process, there are no systematic programs for the retrieval and analysis of TMJ implants in this country. Over the past 15 years there have been numerous scientific reports of the failure of TMJ implants. Despite these reports and the considerable publicity given in public hearings to the consequences of TMJ implant failure, there has not been any systematic study of the medical consequences of TMJ implants, or any studies correlating retrieved implant status to the medical condition of the host. In January 2000, The NIH sponsored a technology assessment conference "Improving Medical Implant Performance Through Retrieval Information: Challenges and Opportunities" that underscored the importance of implant retrieval and analysis in the process of improving the design and use of implants and recommended registries as an approach to address this problem. Subsequent to this NIH conference a FDA Dental Prodeucts Panel meeting was held where it was revealed that there was a paucity of natural history data on patients who had received the TMJ implant under review for approval. Thus, a registry of patients who currently have TMJ implants or who have had TMJ implants would allow investigators to conduct systematic investigations of the consequences of TMJ implant surgery. Information gained by the registry will provide insight into the strengths and weaknesses of the design of these devices, and will enable improvements in future product design. The registry would act as a source of implant material for investigators in the field of medical implant analysis and design. Investigators who have worked on biocompatibility problems of other types of implants might also be interested in expanding their studies to TMJ implants. Access to a sufficiently large number of implants is a hurdle that a registry could help them overcome.
CURRENT PORTFOLIO OVERVIEW
While the NIDCR is the lead NIH Institute regarding TMD research, it currently has little activity in its Extramural Program in the critical areas identified above. Scientists in the Institute's Intramural Program have contacted conducted? a study of the medical condition of a group of about 60 implant patients. These data are currently under review for publication. However, this was not a systematic study of the natural history of implant patients; rather it was a one-time medical assessment of a self-selected group of patients. Therefore, the NIDCR wishes to develop an initiative on TMJ implant retrieval and analysis. Implant retrieval and analysis is of critical importance in the process of improving care of patients in need of implants.
RECOMMENDATIONS FROM RECENT WORKSHOPS
At the 2000 Technology Assessment Conference "Improving Medical Implant Performance Through Retrieval Information: Challenges and Opportunities" the panel addressed a number of key questions (e.g., what information is necessary to evaluate and improve implant and material performance and device design? what future research and institutional support is necessary to ensure continuing advances in implantable devices? what are the patient, health care provider, and societal expectations of the lifetime costs? what are the risks and benefits of medical implants?) and provided recommendations for future research, some of which are listed below:
- the medical device industry should build on their existing strengths to enhance the process of implant retrieval and analysis by sharing information regarding adverse experiences with interested parties;
- patients should be provided with a card containing information about their implant(s), including date of implantation, make, model, and serial number. The card should also serve as an implant "donor" consent form, analogous to an organ donor card, to simplify post-mortem retrieval;
- the NIH and the FDA should be encouraged to develop an aggressive educational program for teaching patients, policymakers, the medical community, and device manufacturers about the importance of device retrieval and analysis. To support this activity, the NIH and the FDA should develop a Web site that links to databases of devices;
- health care practitioners and researchers should define a standard of care in medical implant retrieval and analysis to moderate some of the legal system's disincentives.
The summary of the recommendations of the conference has been published on the BECON web site ( http://consensus.nih.gov/2000/2000MedicalImplantsta019html.htm )
The recommendations of the Technology Assessment Conference will be used as a basis for the development of the RFP.
SCIENTIFIC OPPORTUNITIES
There is a need to document the natural history of patients who have received or currently have different types of TMJ implants. This initiative could serve to attract scientists with expertise in the medical and engineering analysis of implant patients to address problems related to TMJ implants. The availability of a resource containing patient records and retrieved implants is crucial to stimulating scientific investigation in this area.
COLLABORATIVE ACTIVITIES
The recent marketing approval of the TMJ Concepts Patient-Fitted TMJ Reconstruction Prosthesis System highlights the need for the development of this area of research. The Food and Drug Administration (FDA) has expressed an interest in co-sponsoring an initiative to establish a national registry of TMJ implant patients and retrieved TMJ implants.
FUNDING MECHANISMS
The Chronic Diseases Branch recommends the use of the contract mechanism as this would allow the Institute to insure the availability of all registry records and materials to the scientific community as well as having the Government retain ownership to them.
REFERENCES
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Fontenot, M. G., and Kent, J. N. In vitro wear performance of proplast TMJ disc implants. J. Oral Maxillofac. Surgery, 50: 133-139, 1992
Rippert, E. T., Flanigan, T. J., and Middlebrooks, M. M. New design for silastic implants in temporomandibular joint surgery. J. Oral Maxillofac. Surgery, 44: 163-164, 1986
Rooney, T. P., Haug, R. H., Toor, A. H., and Indresano, A. T. Rapid condylar degeneration after glenoid fossa prosthesis insertion: Report of three cases. J. Oral Maxillofac. Surgery, 46: 240-246, 1988