The ultimate goal of the Institute continues to be that of reducing the prevalence of oral-facial malfunction, irrespective of whether it expresses itself in the form of dental caries, periodontal disease, oral cancer or of anomalous oro-facial development. This essential end point can be attained only upon the accumulation and application of a substantially larger body of information regarding causal factors than is presently at hand.

Implementation of the Institute's mission is being served simultaneously by a tripartite research approach involving: 1) basic laboratory investigations of relevance to oro-facial disease; 2) clinical and applied investigations relating to specific disease entities; and 3) epidemiological and field studies, largely directed toward determining feasibility and efficacy of concepts and/or technics generated by the laboratory and clinical endeavors to alleviate oro-facial disease.

Dental Caries

PROGRAM PLANS IN 1967 AND 1968

Basic laboratory studies in the Institute have already demonstrated that a strain of streptococcus is strongly implicated in the genesis of dental decay in laboratory animals. Clinical investigation of so-called "caries susceptible" humans has also revealed that similar bacteria may be isolated from the oral cavity. The recent development of technics which permit isolation, cultivation, and preservation of the human bacterial sample now provides the means whereby additional laboratory and clinical studies may be undertaken, with particular reference to characterizing the organism in terms of its metabolic requirements. and ultimately in terms of its vulnerability to specific antibiotic or related prophylactic measures.

Moreover, these technical developments now permit additional epidemiological study directed toward elucidation of the factors which may influence the preva lence and virulence of this and related organisms in large patient populations. Notwithstanding the probable role of oral microorganisms in the genesis of dental decay, it is now well established that the addition of fluoride, either by direct (topical) application to the teeth, or by its inclusion in the drinking water, can alter the dental enamel in such a way as to make it less susceptible to decay. The Institute takes pride in its past role in the development of this significant contribution to the nation's health, and maintains a strong interest in gathering further knowledge concerning the as yet incompletely documented potential of this unique substance. Consequently, basic laboratory investigations on the mechanism by which the fluoride ion alters enamel structure, especially with respect to its possible use in reversing the early caries process, are con

tinuing. Similarly, considerable effort is being expended in the area of field testing, with emphasis on the epidemiological efficacy of newer methods of topical application of fluoride to the teeth of young people.

Peridontal Disease

As in the case of dental caries, laboratory animal experiments have now revealed that a filamentous microorganism, previously isolated from a diseased periodontium, elicits a response in the host which is clinically similar to human periodontitis. The significance of this finding to the human condition, however, requires much additional study, particularly in terms of characterization of the organism, as well as of its incidence in the normal and diseased human oral cavity.

Laboratory and clinical studies, which emphasize our need to know much more regarding the chemical and metabolic properties of the oral connective tissues, continue to be an integral facet of the Institute's total research endeavor. These studies are designed to determine the nature of the factors which normally influence the synthesis and breakdown of the major structural constituents of connective tissue, proteins, collagen, and elastin, the integrity of which is seriously compromised in periodontal disease. At the clinical level, too, greater emphasis is to be given to the possible role of systemic factors, including nutrition, drugs and hormones, systemic diseases, etc., in determining the susceptibility to and severity of periodonitis. Further clinical and epidemiological effort will be applied to the performance of the relationship between the various clinical signs of periodontal disease and its pattern of development, with the ultimate goal of determining rational methods of clinical therapy, which up to this point in time have been largely empirical.

Oral Cancer

Certain white patches of tissue on the lip, tongue or mouth lining, generally categorized as leukoplakia, are thought to be precancerous. Current research will be expanded to seek more definitive information on the nature of tissue changes in leukoplakia, utilizing biochemical and ultrastructural methods in the laboratory. In addition, clinical and epidemiological investigations of the prevalence and natural history of leukoplakia, with particular reference to environmental factors which may increase the probability of malignant transformation in the lesion, will form an integral part of the total Institute effort with regard to oral cancer.

Growth and Development

Oral clefts, which are among the most common oral-facial defects at birth, result from a failure of the right and left segments forming the lip and the roof of the mouth to unite along a line beginning at the lip and extending through the hard and soft palate. Thus, there is no intact partition between the oral and nasal cavities. Dental abnormalities, such as malformed teeth and arches, are characteristic of this condition. Total collapse of the maxillary arch is common with attendant orthodontic, prosthodontic, and orthopedic problems. Impairment of speech, breathing, and swallowing, and increased susceptibility to upper respiratory infections frequently result.

Successful rehabilitation of the cleft palate child involves the coordinated efforts of many specialists, including orthodontists, prosthodontists, plastic and oral surgeons, otolaryngologists, phychologists, speech therapists, and social workers. It is estimated that the total direct costs for treatment of a single case, covering the period from birth to sixteen years of age, run from $5,000 to $10,000, with variations depending upon the region of the United States in which treatment is given.

In order to clarify the role of genetics and environmental factors in the incidence of cleft palate, detailed genetic, social, medical, and reproductive histories of 100 Pennsylvania families with oral clefts are being obtained. Information emerging from this investigation, as well as currently supported studies on twins, will be useful for both predictive and counseling purposes.

Included in this net increase is $18,000 for mandatory items such as annualization of positions new in 1967, offset by $7,000 for one less day of pay in 1968. There is also an increase of $159,000 for centrally furnished services from the National Institutes of Health Management fund.

These funds will be utilized primarily in research and development of a satisfactory adhesive dental restorative material in collaboration with industrial laboratories, universities, and research organizations.

Collaborative research activity will further emphasize research on implantation and transplantation technics, including basic studies related to tissueimplant/transplant reactions.

In addition it is planned to study the natural cements produced by barnacles, and possibly other aquatic animals or plants, which naturally withstand temperature changes, pressures, reactive chemicals, and still adhere for years to anything solid in an aqueous environment. Moreover, these cements attract mineral salts from water to increase the area of attachment as time goes on. Included in this net increase is $2,000 for centrally furnished services from the National Institutes of Health Management Fund.

Biometric and epidemiological field studies require the application of dental and medical knowledge to human population studies and require original research in mathematical statistics, demography and general methodology for data handling, reduction and analysis.

Epidemiologic studies are being conducted to further clarify the interactions of factors responsible for tooth decay; that is, to determine whether decay producing organisms are natural inhabitants of the oral cavity or whether organisms must be transmitted to the oral cavity before the disease can be established. Another approach is an investigation of the geographic pathology of caries. In this connection, it is planned to conduct field studies in various areas of the Middle East and Africa, such as Ethiopia, where one of the lowest frequencies of tooth decay in the world is found, before encroachments of civilization change this pattern.

Similarly invaluable knowledge can be gained about periodontal disease and growth and development from studies of groups of individuals still living under relatively primitive conditions.

The genetic factor in studies of a broad segment of general population is very much in evidence. For the first time, it has been demonstrated in clinical surveys that heredity is a factor in dental caries.

Included in this net increase is $2,000 for centrally furnished services from the National Institutes of Health Management Fund.

The funds for this activity support the Institute's scientific, managerial, and clerical staff, the National Advisory Dental Research Council and various other subcommittees in the direction and coordination of the grants program. The Council and staff are responsible for stimulating research interest in areas of critical need, reviewing, analyzing, and processing of the research and training grant applications, as well as maintaining a continuing review of ongoing research and training programs.

Included in this net increase is $21,000 for centrally furnished services from the National Institutes of Health Management Fund, offset by $1,000 for one less day of pay in 1968.

This activity supports the overall administration, coordination, and direction of the varied programs and activities of the Institute. The Director and his immediate staff are responsible for the overall program development and review of new areas of focus and interest, as well as introducing new knowledge into current operating programs.

Included in this net increase is $4,000 for centrally furnished services from the National Institutes of Health Management Fund.

NATIONAL INSTITUTE OF ARTHRITIS AND
METABOLIC DISEASES

WITNESSES

DR. G. DONALD WHEDON, DIRECTOR, NATIONAL INSTITUTE OF ARTHRITIS AND METABOLIC DISEASES

DR. JAMES A. SHANNON, DIRECTOR, NATIONAL INSTITUTES OF HEALTH

DR. BENJAMIN T. BURTON, ASSOCIATE DIRECTOR FOR PROGRAM ANALYSIS AND SCIENTIFIC COMMUNICATION, NATIONAL INSTITUTE OF ARTHRITIS AND METABOLIC DISEASES

W. GILBERT BAYLIS, EXECUTIVE OFFICER, NATIONAL INSTITUTE OF ARTHRITIS AND METABOLIC DISEASES

RICHARD L. SEGGEL, EXECUTIVE OFFICER, NATIONAL INSTITUTES OF HEALTH

CHARLES MILLER, FINANCIAL MANAGEMENT OFFICER, NATIONAL INSTITUTES OF HEALTH

DR. WILLIAM H. STEWART, SURGEON GENERAL

G. R. CLAGUE, ACTING CHIEF FINANCE OFFICER

JAMES B. CARDWELL, DEPUTY ASSISTANT SECRETARY, BUDGET