ABSTRACTS 377 a hand and body lotion. Three preservative condi- tions were investigated to give unpreserved, mar- ginally preserved, and preserved products. The in vitro challenge test was based on the CTFA proce- dure but is modified to include product dilutions at four levels (30%, 50%, 70%, 100%). This mod- ification aided in classifying the preservative efficacy of the formulae. The preserved formulae passed the challenge test at all product concentration levels including the most stringent 30% level (Pass 30%). The marginally preserved formulae passed the chal- lenge test at only the 100% product concentration level (Pass 100%). The unpreserved formulae failed the challenge test. Data will be presented to show that the modified CTFA challenge procedure is pre- dictive of the potential for product contamination after consumer use. SESSION II PLAQUE AND GINGIVITIS CLAIMS FOR ORAL HYGIENE PRODUCTS Guidelines for the evaluation of products for the control of plaque and gingivitis Edgar W. Mitchell, Ph.D., American Dental As- sociation, 211 East Chicago Avenue, Chicago, IL 60611 The Council on Dental Therapeutics has reviewed laboratory and clinical studies on products for their safety and efficacy in the control of dental plaque and gingivitis. In its review of data from these studies the Council and its consultants concluded that there is considerable disagreement about the information necessary to conclusively demonstrate product efficacy. There is also disagreement re- garding the design of studies to evaluate these prod- ucts. In an attempt to resolve these issues, the Council developed, in consultation with more than 90 individuals and organizations, guidelines which will be used in reviewing these products in its ac- ceptance program. Products which meet the criteria in these guidelines will be eligible to receive the Seal of Acceptance of the Council. The guidelines and the rationale for their development will be pre- sented. Specific commercial products which have received the Seal of Acceptance and the studies which demonstrated their efficacy will be discussed. FDA and the regulation of prescription drug advertising and promotion Lloyd G. Millstein, Ph.D., Division of Drug Ad- vertising and Labeling, Food and Drug Adminis- tration, Rockville, MD 20857 Disclosures before the Kefauver Subcommittee in 1960-61 led committee members to conclude that advertising to the medical profession had resulted in serious abuses and required new specific controls for the protection of the public. Congress had de- cided that reforms in prescription drug advertising practices were needed because usually favorable fea- tures about a drug were presented in advertising, but side effects, contraindications, warnings, and other limitations regarding usefulness of the drug, as well as other defects that needed regulatory con- sideration, were somehow forgotten or deempha- sized. The Drug Amendments of 1962 corrected some of the prior deficiencies and later drug adver- tising regulations and administrative concepts pro- vided further authority to overcome continued abuses. The 70's began a new era in advertising compliance activities and management. With the evolution of new methods to provide information to the health community, the FDA has entered the 80's with new priorities to examine in the field of promotion and advertising. It continues to exercise oversight in 1) the growing interest to promote products, concepts, and procedures well in advance of their approval, 2) the emerging technologies in electronic communications that have provided mar- keters with more outlets from which to promote their wares to health providers, and 3) the interest in promoting prescription products directly to con- sumers. Because of these and other current issues, the FDA is concerned about turmoil in the mar- ketplace and whether further sanctions on current advertising practices will be necessary. Influence of mechanical aspects of dentifrice and toothbrush in plaque control L. P. Cancro, Morton Pader, Ph.D., Shirley S. Birenz, and Patricia Pretara Spanedda, Lever Brothers Co. Research Center, 45 River Road, Edgewater, NJ 07020 The toothbrush is the most popular mechanical de- vice for cleaning teeth. The efficiency of tooth- brushing is assessed in regard to varying brushing times, toothbrushing frequency, dentifrice load, and dentifrice abrasivity. Studies of the duration of toothbrushing time involving children and adults suggested that the average "scrub" time for children as well as adults is approximately 20 seconds. The wearout rate of toothbrushes is directly related to the number of filaments in a tuft and filament di- ameter, whereas cleansing features appear to have an inverse relationship to filament diameter: thicker filaments last longer but fail to clean as well as thinner filaments. Toothbrush configuration, shape, and size have not been clearly demonstrated to be dominant factors associated with toothbrush efficacy. A system facilitating plaque removal via com- bination of chemical and mechanical proce- dures

378 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS R. L. Goldemberg, Rakuma Laboratories, Inc., P.O. Box 2083, South Hackensack, NJ 07606 The development of a new modality for plaque re- moval is described--use of a plaque-loosening dental rinse prior to brushing. The functionality of such pre-rinses mandates formulations different from products intended for postbrushing or mouth- freshening uses. The pre-brushing rinse has a higher pH and contains surfactants and analgesic ingredi- ents. Antimicrobial activity is secondary in terms of functionality of such pre-rinses. Significant effi- cacy of this dental rinse has been demonstrated in laboratory and clinical tests. Chlorhexidine•a unique chemical for control of gingivitis W. Briner, Ph.D., The Procter and Gamble Co., 11511 Reed Hartman Highway, Cincinnati, OH 45241. Chlorhexidine has been shown effective in control- ling gingivitis for months and can be a lifesaving drug in the immunosuppressed. Chlorhexidine is a bisbiguanide of the following structure: NH NF Cl- O- NH.C.NH.C.NH. (CH2)6.NH.C.NH.C.NH - \•-Cl NH NH Chemistry, Toxicity, and Uses: It has the charac- teristics of a cationic surfactant. Chlorhexidine is relatively nontoxic. It is poorly absorbed in the gut, most passing through unchanged. The reported side effects from oral use include extrinsic staining of teeth and a slight transient desquamation, neither of which limits usefulness of the drug. It is used in surgical scrubs, disinfection of contact lenses, etc. It is available in some countries as a dental gel or as a mouthrinse. Microbiology: Chlorhexidine is a broad spectrum antimicrobial agent which is effective against a number of oral microorganisms. After a single rinse with chlorhexidine, about 30% is retained in the oral cavity and this is slowly released into saliva, maintaining effective levels for several hours. This is perceived as contributing to the efficacy of chlor- hexidine in the mouth. In humans, slight (about twofold) increases in resistance of oral bacteria to chlorhexidine have been observed during mouthrins- ing. However, these increases dissipated or disap- peared after cessation of use and did not limit ef- ficacy of the drug. In vivo studies: Studies in dogs have shown chlor- hexidine effective in controlling gingivitis for up to seven years with no loss of alveolar bone. No mean- ingful increases in resistance of oral bacteria were observed. Under the severe challenge of the exper- imental gingivitis model in humans, no oral hy- giene for three weeks, a chlorhexidine mouthrinse maintained gingivial health virtually unchanged from baseline. In clinical trials of 19nger duration, chlorhexidine mouthrinses have been shown to re- duce gingivitis up to 80% in comparison with pla- cebo' while establishing a level of gingival health similar to that of chlorhexidine in the experimental gingivitis model. Reductions in the number of bac- teria in the oral cavity have been documented during rinsing with chlorhexidine. In immunosup- pressed patients undergoing bone marrow trans- plants, a chlorhexidine mouthrinse has been shown to decrease candida and candida-associated mor- bidity and mortality. In this setting it may be con- sidered a lifesaving drug. Chlorhexidine today is the standard of comparison for any agent claiming antigingivitis efficacy. In clinical trial, chlorhexidine has produced reductions in gingivitis up to 80% while maintaining excellent gingival health for months. It can be a lifesaving drug in immunosuppressed patients. Essential oils Robert C. Emling, University of Pennsylvania, School of Dental Medicine, 4001 Spruce Street, Philadelphia, PA 19104 Essential oils, such as thymol, menthol, and euca- lyptol, have been used in mouth rinses for over 100 years. These ingredients in mouth rinses have been documented to be antibacterial in laboratory tests. With the scientific association of microorganisms and plaque formation, and the suspected involve- ment of this process with carious lesions and gin- givitis, the effect of essential oils on these processes have taken on new interests. For the past decade, products containing essential oils have been studied clinically for their role in oral health status. The studies have assessed short-term effects which occur within one or two weeks. Other studies have run for six months. Some studies have been conducted with no other oral hygiene than the mouth rinse alone, while others have allowed the use of the mouth rinses in an unsupervised setting of "usual home care." Almost uniformly, the results of the studies have been favorable to the products con- taining essential oils. In general, these products have retarded the development of plaque and have reduced the severity of gingivitis. The studies have also compared products containing essential oils to control groups using only a vehicle, or against plain water rinses. The results of these assessments have generally shown products containing essential oils to be more effective than the controls, thus pointing to the fact that these agents are active ingredients. Sanguinaria/sanguinarine in the control of plaque and gingivitis G. Lee Sourhard, Ph.D., Vipont Laboratories, Inc., Fort Collins, CO 80524 In the past few years sanguinaria products have been