[Federal Register Volume 59, Number 243 (Tuesday, December 20, 1994)] [Unknown Section] [Page 0] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 94-31161] [[Page Unknown]] [Federal Register: December 20, 1994] ======================================================================= ----------------------------------------------------------------------- DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 872 [Docket No. 92N-0281] Medical Devices; Classification of Temporomandibular Joint Implants AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. ----------------------------------------------------------------------- SUMMARY: The Food and Drug Administration (FDA) is classifying four temporomandibular joint (TMJ) implants, the total temporomandibular joint prosthesis, the glenoid fossa prosthesis, the mandibular condyle prosthesis, and the interarticular disc prosthesis (interpositional implant), into class III (premarket approval). These actions are being taken under the Federal Food, Drug, and Cosmetic Act (the act), as amended by the Medical Device Amendments of 1976 (the 1976 amendments) and the Safe Medical Devices Act of 1990 (the SMDA). EFFECTIVE DATE: January 19, 1995. FOR FURTHER INFORMATION CONTACT: Joseph M. Sheehan, Center for Devices and Radiological Health (HFZ-84), Food and Drug Administration, 2098 Gaither Rd., Rockville, MD 20850, 301-594-4765, ext. 157. SUPPLEMENTARY INFORMATION: I. Background In the Federal Register of September 18, 1992 (57 FR 43165), FDA issued a proposed rule to classify certain TMJ implants into class III. Initially, FDA provided for interested persons to submit written comments on the proposal by November 17, 1992. In response to a request for an extension of the comment period, in the Federal Register of December 1, 1992 (57 FR 56876), FDA extended the comment period until December 8, 1992. Subsequently, in the Federal Register of February 14, 1994 (59 FR 6935), FDA reproposed to classify two TMJ implants, the mandibular condyle prosthesis and the glenoid fossa prosthesis, into class III (premarket approval) to reflect the recommendation of the Dental Products Panel (the panel) with respect to the classification of these devices. II. Response to Comments The agency received 54 comments responding to the proposed rule and one comment responding to the reproposed rule. These comments were submitted by a law firm, oral and maxillofacial surgeons who placed TMJ implants, manufacturers and distributors of TMJ implants, and TMJ implant recipients. 1. In the preamble to the proposed rule, FDA advised interested persons that the agency lacked evidence that the total TMJ prosthesis was legally in commercial distribution before May 28, 1976. If the device was first introduced into interstate commerce after May 28, 1976, it would be in class III in accordance with section 513 of the act (21 U.S.C. 360c). FDA specifically requested comments on this issue. In response, FDA received several comments stating that the total TMJ prosthesis was legally in commercial distribution in the United States before May 28, 1976, and one comment to the contrary. FDA has determined, from information submitted in comments, that two firms, TMJ Implants, Inc., Golden, CO, and the Temporomandibular Joint Research Foundation, La Cresenta, CA, were commercially distributing the total TMJ prosthesis in the United States on or before May 28, 1976. Thus, the agency has concluded that the total TMJ prosthesis is, in fact, a preamendments device and should be classified along with the other TMJ implants. 2. Several comments stated that classification of TMJ implants into class III (premarket approval) might result in the unavailability of these devices for clinical use or in a movement to ban them. One manufacturer of total TMJ implants stated that, if the total TMJ implant is classified into class III, the expense of preparing a PMA would force that manufacturer to discontinue marketing the device. Under the statute, FDA classifies a device into class III, and subsequently requires submission of PMA's for the device, when FDA has determined that premarket approval is necessary to provide reasonable assurance of the safety and effectiveness of the device. The classification of a device, therefore, is based on considerations related to the safety or effectiveness of the device. FDA disagrees that classifying TMJ implants into class III will necessarily result in the unavailability and/or the banning of these devices because of the procedural safeguards contained in the statute. The effect of classifying a device into class III is to provide each manufacturer of the device with sufficient time to conduct necessary testing of the device (a minimum of 30 months) and then to submit a PMA to FDA by a date to be set in a future regulation under section 515(b) of the act (21 U.S.C. 360e(b)(1)). That regulation is promulgated using notice-and-comment rulemaking, in conjunction with which manufacturers are permitted to petition for reclassification. Moreover, pursuant to section 501(f) of the act (21 U.S.C. 351(f)(1)), a preamendments device may continue to be sold throughout this time period and while a PMA is pending. FDA is not attempting to ban TMJ implants by classifying them into class III. In fact, by eventually requiring submission of PMA's for these devices, FDA will be giving manufacturers the opportunity to establish that the devices are safe and effective. The classification of a device into class III neither results in nor is it related to the banning of a device under section 516 of the act (21 U.S.C. 360f). 3. Several comments stated that, for reconstruction of the temporomandibular joint, non-ProplastTM TMJ implant devices are superior to autogenous materials. One comment stated that partial fossa protheses are safe and effective. Comments from patients and TMJ prostheses manufacturers stated that they experienced favorable results following implantation of the total TMJ prosthesis. In classifying these devices, FDA is determining the level of regulatory control needed to provide reasonable assurance of their safety and effectiveness. Whether non-ProplastTM TMJ implants are superior in safety and effectiveness to autogenous materials, or whether partial fossa prostheses are perceived as safe and effective, is not relevant to this determination. In accordance with section 513(a)(3) of the act, the agency relies on valid scientific evidence to determine the classification of a device. According to Sec. 860.7(c)(2) (21 CFR 860.7(c)(2)), valid scientific evidence includes evidence from well-controlled investigations, partially controlled studies, studies and objective trials without matched controls, well-documented case histories conducted by qualified experts, and reports of significant human experience with a marketed device. Valid scientific evidence does not include isolated case reports, random experience, reports lacking sufficient details to permit scientific evaluation, or unsubstantiated opinions. Thus, the isolated case reports, random testimonials, and unsubstantiated opinions received in response to the proposed rule cannot be regarded as valid scientific evidence upon which the classification of TMJ implants can be based. 4. One comment stated that the agency's failure to provide the panel information relating to TMJ devices made of materials other than ProplastTM limited the panel's consideration and should limit the scope of its classification recommendation accordingly. FDA disagrees with this comment. As stated in the legislative history of the Medical Device Amendments of 1976: In requiring a panel's classification recommendation to include a summary of the reasons for the recommendation and a summary of the data upon which the recommendation is based, the objective is to assure that the record accurately reflects the basis for the panel's recommendations. The use of the term ``data'' is not intended to refer only to the results of scientific experiments but should also consist of less formal evidence, other scientific information, or judgments of experts when available. The requirement is not intended to imply that a panel must have received evidence with respect to safety and effectiveness of a device before it can make a classification recommendation. Under this premise, the burden of providing evidence substantiating the safety and effectiveness of a device rests on the manufacturers, and the absence of sufficient data may be referred to in a panel's recommendation as the reason for classification of a device into class III. (See H. Rept. No. 94-853, 94th Cong., 2d sess. 40 (1976), p. 40). 5. One comment asserted that the references cited by FDA in the proposed rule classifying the total TMJ implant did not exist at the time of the panel meeting and, therefore, could not have been evaluated by the panel when making its recommendation. FDA disagrees with this comment. It is true that some of the information cited by FDA in support of its proposed classification of the total TMJ implant did not exist at the time of the panel's April 21, 1989, meeting. However, the proposed rule reflected not only the panel's recommendations, but also FDA's determinations regarding the proper classification of these devices. The proposed rule did not state or imply that the panel relied on all the data cited by the agency in support of the proposed rule. 6. Several comments suggested that, when classifying these devices, FDA should distinguish TMJ prostheses containing ProplastTM from those not containing that material. These comments recommended that only devices containing ProplastTM should be classified. Some comments stated that the risks to health identified in the proposed rule are based only on data associated with the failure of TMJ prostheses containing ProplastTM. One comment stated that ProplastTM implants and non-ProplastTM implants (specifically cobalt chrome and polymethylmethacrylate (PMMA) prostheses) should be classified separately because the difference in the material used in these implants significantly affects their safety and effectiveness. Several comments stated that surgeons and TMJ implant manufacturers had observed no specific cases of the risks to health identified in the proposed rule in several patients implanted with a non-ProplastTM total TMJ prosthesis. Some comments stated that these risks to health were not observed in patients implanted with TMJ prostheses manufactured by specific manufacturers. In contrast, several comments said that these risks were observed often in patients implanted with TMJ implants containing ProplastTM. According to Sec. 860.5(c)(3), when FDA initially classifies a device, it may consider safety and effectiveness data developed for other devices of the same generic type. A generic type of device includes devices that do not differ significantly in purpose, design, material, energy source, function, or any other feature related to safety and effectiveness, and for which similar regulatory controls are sufficient to provide reasonable assurance of safety and effectiveness (see Sec. 860.3(i)). The transcript of the April 21, 1989, panel meeting demonstrates that the panel considered TMJ implants composed of various materials, i.e., silicone, ProplastTM, dural grafts, fascia, vitallium, acrylic, meniscle and silastic, before making its recommendations with respect to classification. Evidence submitted during the panel meeting revealed that similar risks and similar safety and effectiveness concerns are associated with all TMJ implants, regardless of material composition. Based on the evidence provided, the panel concluded that TMJ devices composed of different materials raise the same safety and effectiveness questions. Thus, the panel concluded, and FDA agrees, that TMJ implants of all materials should be regulated within the four generic types of devices identified because the devices do not differ significantly in the safety and effectiveness questions raised and, consequently, similar regulatory controls will be needed to provide reasonable assurance of their safety and effectiveness. 7. Comments stated that one of the health risks identified in the proposed rule, loosening of the total TMJ prosthesis, is directly related to the health of the bone at the implant interface. These comments asserted that loosening of the device does not occur unless there is a void of suitable bone. As stated in the preamble to the proposed rule, FDA has determined that the screws used to anchor the implant may loosen, resulting in implant loosening or displacement which may cause changes in bite, difficulty in chewing, limited joint function and unpredictable wear on implant components (see Refs. 2 through 5). The agency has not received any new information to cause FDA to change its opinion. 8. Some comments asserted that FDA should classify all the TMJ implants into class II because special controls would allow the agency to impose special conditions on these devices, such as postmarket surveillance. One of these comments, received from a TMJ implant manufacturer, recommended that FDA classify TMJ cobalt-chrome-PMMA implants into class II. FDA disagrees with these comments. FDA believes that insufficient information exists to establish that special controls would provide reasonable assurance of the safety and effectiveness of these devices. FDA believes that a PMA is necessary to provide such assurance. Furthermore, postmarket surveillance is not limited to class II devices. Thus, at some future time, FDA may request that manufacturers of TMJ implants conduct postmarket surveillance of these devices. 9. One comment urged that the total temporomandibular joint prosthesis and the interarticular implant be given high priority in calling for PMA's. One comment disagreed, stating that FDA cannot give the total TMJ prosthesis high priority in calling for PMA's when the panel recommended low priority. Another comment expressed concern that manufacturers of these prostheses will not have to submit PMA's to FDA for at least 2\1/2\ years and will be permitted to market the devices in the interim. Pursuant to sections 501(f) and 515(b) of the act, TMJ implant manufacturers may continue to commercially distribute their devices without filing a PMA for 30 months after the effective date of the final rule classifying these implants into class III or until 90 days after FDA issues a final rule requiring premarket approval for the devices, whichever is later. Moreover, section 515(i) of the act shows a clear congressional intent that FDA move forward with requiring the submission of PMA's for all preamendments devices. Thus, regardless of the priority assigned for calling for PMA's, eventually PMA's will be required for all class III preamendments devices that are not reclassified. Furthermore, it should be noted that a panel recommendation is only a recommendation that FDA may adopt or reject. FDA believes that it is appropriate to require PMA's for all TMJ implants as soon as possible under the act. 10. Two comments objected that the glenoid fossa prosthesis and the mandibular condyle prosthesis should not be classified into class III because the panel did not recommend that they be classified into class III. Subsequent to issuing the proposed rule, the panel reconvened on February 11, 1993, and recommended that the mandibular condyle prosthesis and the glenoid fossa prosthesis be classified into class III. Based on this recommendation, FDA issued a reproposed rule in the Federal Register of February 14, 1994 (59 FR 6935), to classify the devices into class III. 11. One comment stated that the classification process for the TMJ implants was flawed and should be reinitiated because of events which transpired between the April 1989 panel recommendation and the issuance of the proposed rule. During this time, the SMDA was passed. Among other things, the SMDA changed the classification definitions for medical devices. FDA disagrees with this comment. It is the agency's position that the SMDA does not require the agency to obtain a new classification recommendation from a panel which had recommended classification under the previous standard. As stated previously, the agency is not bound to adopt a panel's recommendation. Moreover, in light of the significant risks to health identified by the panel, FDA believes it is extremely unlikely that the panel would have recommended that the devices be classified into class II under the new definition. 12. On its own initiative, FDA has deleted the words, ``naturally occurring'' from the identifications of glenoid fossa prosthesis and mandibular condyle prosthesis because the standard of care now indicates that these devices may now interface not only with naturally occurring surfaces but also with artificial surfaces. III. References The following referencees have been placed on display in the Dockets Management Branch (address above) and may be seen by interested persons between 9 a.m. and 4 p.m., Monday through Friday. 1. Transcripts of the Dental Products Panel meeting, April 21, 1989. 2. Transcripts of the Dental Products Panel meeting, February 11, 1993. 3. Fontenot, M. G., and J. N. Kent, ``In-vitro and In-Vivo Wear Performance of TMJ Implants,'' abstract, International Association of Dental Research, 1991. 4. Kent, J. N., and M. S. Block, ``Comparison of FEP and UPE Glenoid Fossa Prosthesis,'' abstract, International Association of Dental Research, 1991. 5. ``Clinical Information on the Vitek TMJ Interpositional (IPI) Implant and the Vitek-Kent (VK) and Vitek-Kent 1 (VK-1) TMJ Implants,'' and ``Vitek Patient Notification Program,'' an FDA publication, 1991. 6. Kent, J. N., ``VK Partial and Total Joint Reconstruction,'' Current Concepts of TMJ Total Joint Replacement, University of Medicine and Dentistry of New Jersey, pp. 1-8, March 1992. 7. Primely, D., Jr., ``Histological and Radiological Evaluation of the ProplastTM-Teflon Interpositional Implant in Temporomandibular Joint Reconstruction Following Meniscectomy,'' thesis, Master Degree in Oral Maxillofacial Surgery, University of Iowa, May 1987. 8. Westlund, K. J., ``An Evaluation Using Computerized Tomography of Clinically Asymptomatic Patients Following Meniscectomy and Temporomandibular Joint Reconstruction Using the ProplastTM-Teflon Interpositional Implant,'' thesis, Masters Degree in Oral and Maxillofacial Surgery, University of Iowa,May 1989. 9. Wagner, J. D., and E. L. Mosby, ``Assessment of ProplastTM-Teflon Disc Replacements,'' Journal of Oral and Maxillofacial Surgery, 48:1140-1144, 1990. 10. Florine, B. K., et al., ``Tomographic Evaluation of Temporomandibular Joints Following Discoplasty or Placement of Polytetrafluoroethylene Implants,'' Journal of Oral and Maxillofacial Surgery, 48:183-188, 1988. 11. Heffez, L., et al., ``CT Evaluation of TMJ Disc Replacement with a ProplastTM Teflon Laminate,'' Journal of Oral and Maxillofacial Surgery, 45:657-665, 1987. 12. Ryan, D. E., ``Alloplastic Implants in the Temporomandibular Joint,'' Oral and Maxillofacial Surgery Clinics of North America, 1:427, 1989. 13. Valentine, J. D., ``Light and Electron Microscopic Evaluation of ProplastTM II TMJ Disc Implants,'' Journal of Oral and Maxillofacial Surgery, 47:689-696, 1989. 14. Logrotteria, L., et. al., ``Patient with Lymphadenopathy Following Temporomandibular Joint Arthroplasty with ProplastTM,'' The Hour of Craniomandibular Practice, vol. 4, No. 2:172-178, 1986. 15. Berarduci, J. P., et al., ``Perforation into Middle Cranial Fossa as a Sequel to Use of a ProplastTM-Teflon Implant for Temporomandibular Joint Reconstruction,'' Journal of Oral and Maxillofacial Surgery, 46:496-498, 1990. 16. Berman, D. N., and S. L. Pronstein, ``Osteo Phytic Reaction to a Polytetrafluoroethylene Temporomandibular Joint Implant,'' Oral Surgery, Oral Medicine, Oral Pathology (continues the Oral Surgery Section of the American Journal of Orthodontics and Oral Surgery), 69:20-23, 1990. IV. Environmental Imapct The agency has determined under 21 CFR 25.24(e)(2) that this action is of a type that does not individually or cumulatively have a significant effect on the human environment. Therefore, neither an environmental assessment nor an environmental impact statement is required. V. Analysis of Impacts FDA has examined the impacts of the final rule under Executive Order 12866 and the Regulatory Flexibility Act (Pub. L. 96-54). Executive Order 12866 directs agencies to assess all costs and benefits of available regulatory alternatives and, when regulation is necessary, to select regulatory approaches that maximize net benefits (including potential economic, environmental, public health and safety, and other advantages; distributive impacts; and equity). The agency believes that this final rule is consistent with the regulatory philosophy and principles identified in the Executive Order. In addition, the final rule is not a significant regulatory action as defined by the Executive Order and so is not subject to review under the Executive Order. The Regulatory Flexibility Act requires agencies to analyze regulatory options that would minimize any significant impact of a rule on small entities. Because this rule does not impose any new requirements, the agency certifies that the final rule will not have a significant economic impact on a substantial number of small entities. Therefore, under the Regulatory Flexibility Act, no further analysis is required. List of Subjects in 21 CFR Part 872 Medical devices. Therefore, under the Federal Food, Drug, and Cosmetic Act, and under authority delegated to the Commissioner of Food and Drugs, 21 CFR part 872 is amended as follows: PART 872--DENTAL DEVICES 1. The authority citation for 21 CFR part 872 continues to read as follows: Authority: Secs. 501, 510, 513, 515, 520, 701 of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 351, 360, 360c, 360e, 360j, 371). 2. New Secs. 872.3940, 872.3950, 872.3960, and 872.3970 are added to subpart D to read as follows: Sec. 872.3940 Total temporomandibular joint prosthesis. (a) Identification. A total temporomandibular joint prosthesis is a device that is intended to be implanted in the human jaw to replace the mandibular condyle and augment the glenoid fossa to functionally reconstruct the temporomandibular joint. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. The effective date of the requirement for premarket approval has not been established. See Sec. 872.3. Sec. 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the temporomandibular joint to augment a glenoid fossa or to provide an articulation surface for the head of a mandibular condyle. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. The effective date of the requirement for premarket approval has not been established. See Sec. 872.3. Sec. 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to replace the mandibular condyle and to articulate within a glenoid fossa. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. The effective date of the requirement for premarket approval has not been established. See Sec. 872.3. Sec. 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc prosthesis (interpositional implant) is a device that is intended to be an interface between the natural articulating surface of the mandibular condyle and glenoid fossa. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. The effective date of the requirement for premarket approval hasnot been established. See Sec. 872.3. Dated: November 25, 1994. D. B. Burlington, Director, Center for Devices and Radiological Health. [FR Doc. 94-31161 Filed 12-19-94; 8:45 am] BILLING CODE 4160-01-F