NIST, which was established in 1901 as the National Bureau of Standards (NBS), has a materials research program that is recognized worldwide. As a non-regulatory agency, NIST is conducting research on dental materials to support the safe, efficient and economical use of materials for the benefit of consumers and the practicing dental professional.
The first dental materials research project at the former bureau was for the U.S. Army Dental Corps in 1919. The Army asked NBS for assistance in writing a purchase standard based on physical property measurements for amalgam dental filling material. The report, which had an immediate influence on the manufacture of alloys for amalgams, provided dentists with the first unbiased source of information on the material.
The dental materials program at NIST is a cooperative activity involving researchers from the institute's Polymers Division (a part of the NIST Materials Science and Engineering Laboratory); research associates from the American Dental Association (ADA) Health Foundation, the National Institute of Dental Research (NIDR), and the dental materials industry; and guest scientists from the U.S. Navy Dental Corps and others from domestic and foreign universities in the dental field.
The NIST dental materials program is a long-standing model of cooperation between the private sector and government. Researchers from the dental profession, industry and government have worked together at NIST since 1920 to improve dental materials nd devices.
The National Institute of Dental Research, located in Bethesda, Md., was established in 1948 by Congress as one of the first three National Institutes of Health (NIH). It is the primary sponsor of dental research and related training in the United States.
NIDR conducts research through intramural programs and through grant-funded extramural programs that range from laboratory studies on the basic causes of craniofacial, oral and dental diseases to clinical trials of new diagnostics, therapies and materials, and oral health promotion. NIDR grants are a major source of funding for the ADA research associates at NIST.
NIDR established a joint research program at NIST in 1984 to study the chemistry of calcium compounds and how they relate to living systems. NIDR was interested in combining its biologically oriented work at NIH with existing NIST chemical research on calcium phosphate compounds in its effort to develop such compounds for dental and biomedical materials applications.
Both NIDR and NIST have a long-standing rapport with manufacturers and users in the dental industry. The NIDR sponsored program at NIST combines the institute's experience in developing dental material specifications with NIDR's mission to improve the nation's oral health. The joint program also is an important part of a major effort by NIST to transfer the federal investment in materials research to benefit the public.
The ADA, founded in 1859 and headquartered in Chicago, Ill., is the largest organization of dental professionals, representing more than 141,000 members in the United States.
The goal of the ADA is to "encourage the improement of the health of the public and to promote the art and science of dentistry."
The ADA established a research associate program at NBS in 1928 after a report was published by the bureau summarizing eight years of research on the composition, properties and techniques associated with the materials and accessories used in casting dental appliances.
Dr. Norris O. Taylor was the first ADA researcher at NBS. In 1930 he reported on a specification for dental amalgam that marked the beginning of an extensive specification program at NBS by the ADA. The specification program was moved to ADA headquarters in 1966.
The research activities of the ADA were transferred to the ADA Health Foundation, established in 1964 as a 501(c)(3) non-profit organization whose central mission is to advance the oral health of the public by providing funds for basic and applied dental research and education. The ADA research unit was renamed the Paffenbarger Research Center in 1985 in honor of Dr. George C. Paffenbarger, who was the unit's first director from 1929 to 1974.
The NIST program addresses primarily the development of new and improved dental materials, which represents $573 million of the more than $2 billion in dental equipment and supplies shipped by U.S. industry in 1995. Exports account for approximately 20 percent of domestic shipments, giving U.S. companies a positive balance of trade. The institute program also has included research on instruments, equipment and uses of materials to assist the dentist in diagnosis and treatment of dental diseases and in tooth restorations.
The major research areas include:
- new and improved ways to bond composite and other restorative materials to teeth;
- improvements in the durability and other properties of resins and composites used to protect and restore teeth;
- new cements for tooth restorations and a biocompatible calcium phosphate cement that forms the same composition as the natural minerals in teeth and bone;
- improved fluoride treatments and rinses to reduce tooth decay;
- esthetic glass-ceramics for tooth restorations;
- chewing gums and other applications of compositions that desensitize sensitive teeth and reverse early stages of tooth decay;
- an investigation of the instrumentation and techniques required for dentists to successfully use a NIST-developed metallic filling material that contains no mercury; and
- calcium phosphate-specific electrodes and microanalytical instrumentation techniques.
Approximately 40 dental materials scientists work at the institute. The majority are research associates employed by the ADA Health Foundation; others are intramural research staff from the NIDR; some are staff members in the NIST dental and medical materials group; and there are varying numbers of guest scientists from the armed forces, universities and dental manufacturers.
The research associates at NIST are scientists whose salaries are paid by the sponsoring organizations while they work at NIST on projects of mutual interest.
Guest scientists working at NIST have come from Howard University Dental School (Washington, D.C.), Tokyo Medical and Dental University (Japan), McGill University Dental School (Montreal, Canada), Western Ontario University Dental School (London, Canada), and the U.S. Naval Dental Clinic (Bethesda, Md.).
The program also has had recent industry support from SmithKline Beecham, Colgate-Palmolive, Osteogenics Inc. and Nabisco.
Approximately 55 ADA specifications have been developed and adopted by the American National Standards Institute (ANSI). While the first ones were based solely on materials research at NBS, those developed after 1966 under the ADA's Council on Dental Materials, Instruments and Equipment have involved participation by other research groups and manufacturers. The specification program is now carried out under the auspices of the ADA Council on Scientific Affairs.
Neither NIST nor the ADA have any regulatory role. For regulatory purposes, NIST and the ADA work with the Food and Drug Administration in the classification and review of products intended for human use under the provisions of the Safe Medical Devices Act of 1976, revised in 1990.
The ADA sponsors various specifications for dental materials, instruments and equipment through the procedures of ANSI Committee MD156. The committee includes representatives from industry, research laboratories, dental schools, federal agencies and others concerned with the development of voluntary standards. NIST researchers are among those participating on this committee.
Individual ental researchers and manufacturers participate in the development of international standards through ANSI, which is the U.S. member of the International Organization for Standardization (ISO) based in Geneva, Switzerland. The ADA also is the U.S. member of the International Dental Federation, based in London, which cooperates with the ISO in formulating international standards concerning the properties of dental products.
NIST dental researchers and medical industry representatives also participate in the development of test methods for medical and dental devices through ASTM Committee F-4 on Medical and Surgical Materials and Devices.
NIST and ADA researchers maintain contact with the American Dental Trade Association, which develops guidelines and procedures for more than 150 manufacturers and distributors of dental supplies, instruments and equipment, and the 3,000 member National Association of Dental Laboratories, which runs a laboratory certification program.
The ADA has a program used by manufacturers to certify that their products comply with ADA specifications. Manufacturers supply supporting test data to show compliance, and samples of products from the open market are evaluated by the ADA Research Institute in Chicago for compliance.
The ADA Health Foundation (ADAHF) has the option to retain title to any invention involving materials, instruments and equipment that is invented solely by ADA research associates at NIST. Thus, the ADAHF will be sole owner of these inventions and, as such, may choose to license these inventions to manufacturers. TheADAHF also agrees to grant the U.S. government a governmental use license, which is essentially a royalty-free type of license.
For NIST solely owned inventions, NIST scientists must assign all title, right and interest in each invention to NIST, on behalf of the U.S. government. NIST then may release these rights to employee inventors or to the ADAHF subject to a governmental use license.
In addition, NIST and the ADAHF have the option to retain joint title to inventions made jointly by ADAHF research associates and NIST employees. If either party does not wish to take title to a joint invention, it will offer to assign its interest to the other party subject to a non-exclusive, irrevocable, paid-up license to practice, or have practiced, the invention throughout the world. All licenses include the right to grant sublicenses.
The institute does not conduct clinical studies as part of the NIST dental materials research program. The ADA Health Foundation, however, conducts clinical studies at NIST under protocols approved by both the ADA and NIST Institutional Review Boards for the protection of human research subjects. These studies are partially supported by NIDR and are occasionally conducted in cooperation with universities and other research groups.
NIST collaborative research has made many contributions to improved dental science. They include:
- the invention of composite resins for esthetic tooth restorations and successful adhesion systems for bonding composites to hard tooth tissues;
- the synthesis of BIS-GMA, the most widely used polymric hardening component in composites, tooth sealants and orthodontic bracket bonding agents;
- the first radiation protection devices and procedures requiring less mercury; the panoramic X-ray machine; and
- the prototype for the modern high-speed dental drill.
The panoramic X-ray and high-speed drill not only have increased the comfort and effectiveness of dental treatment but have saved the nation several billion dollars by reducing the time required by dentists to treat patients. By decreasing the replacement costs of the less serviceable materials they replaced, dental composites were estimated in 1987 to save Americans more than the combined annual appropriated budgets of the three institutions that sponsored dental composites research at that time--NIST, NIDR and the ADA.
For additional information on the dental materials research programs, contact:
--Francis W. Wang, Group Leader, NIST Dental and Medical Materials Group, NIST, 100 Bureau Drive, Stop 8545, Gaithersburg, Md. 20899-8545, (301) 975-6726, fax: (301) 977-2018, e-mail: fwang@nist.gov.
Contact: inquiries@nist.gov
Last Update: April 9, 1999