210 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS (13) J. Garcia Dominguez, F. Balaguer, J. L. Parra, and C. M. Pelejero, The inhibitory effect of some amphoteric surfactants on the irritation of alkylsulfates, Int. J. Cosmet. Sci., 3, 57-68 (1981). (14) R. Ernst, Surface active betaines as protective agents against denaturation of an enzyme by alkyl sulfate detergents, J. Am. Oil Chem. Soc., 57, 93-98 (1980). (15) K. Miyazawa, M. Ogawa, and T. Mitsui, The physico-chemical properties and protein denaturation potential of surfactant mixtures, Int. J. Cosmet. Sci., 6, 33-46 (1984). (16) Patent, Fr. 1,403,213, Marchon Products Ltd., May 1965. (17) J. Garcia-Dominguez, J. L. Parra, M. R. Infante, C. M. Pelejero, F. Balaguer, and T. Sastre, A new approach to the theory of adsorption and permeability of surfactants on keratinic proteins: The specific behavior of certain hydrophobic chains, J. Soc. Cosmet. Chem., 28 165-182 (1977).

J. Soc. Cosmet. Chem., 37, 211-223 (July/August 1986) Parameters for assessing the cleaning power of toothpastes H.-J. KLf3PPEL, W. PLOGER, F. FORG, and W. UMBACH Henkel KGaA, D-4000 Di•)seldorf, P.O. Box 1100, West Germany Received December 12,1985. Synopsis The cleaning effect of a dentifrice with respect to dental stain is usually regarded as dependent on the extent of its dentin abrasion. Accordingly, the use of products with high cleaning power is supposed to necessarily involve the risk of possible damage to dentin at the dentin-enamel junction. Our own tests, however, have shown that for nonscratching and polishing toothpastes this relationship only exists theoretically. Under given conditions, enamel abrasion is obviously the major factor in achieving a good cleaning effect. On the basis of this concept, marketable products can be developed with high cleaning power and low dentin abrasion. INTRODUCTION It goes without saying nowadays that the use of dentifrice in the form of a toothpaste or toothpowder is indispensable to maintaining good oral hygiene. Its purpose is to keep teeth free of bacterial plaque, extrinsic dental stain, and tartar. This is generally achieved by the tooth cleaning agents (synonyms: polishing agents, abrasives) and sur- factants contained in these dentifrices (1). The view may be correct that plaque removal is also possible merely with toothbrush and water given appropriate time and effort. Clinical tests conclusively prove, however, that the results of toothbrushing with a dentifrice are considerably more favorable and enduring (2,3). The polishing effect of the dentifrice may also be significant at least to some extent, as smooth surfaces become less quickly re-infested with bacteria than rough ones (4-8). After all, the removal of extrinsic dental stain is not possible without cleaning agents anyway (9-13). According to the current state of knowledge, dental stain arises due to pellicle discoloration. This may, for example, be due to the con- sumption of tea or coffee, the smoking of tobacco, or the use of prophylactic or medic- inal preparations such as chlorhexidine mouthwash solutions (14-18). As early as 1907, Miller (19) recognized that certain cleaning agents can cause unaccept- able abrasive damage to the tooth, especially at the sensitive enamel-cementum bor- derline (20). Since then, the question has been raised as to what properties cleaning Dedicated to Dr. Konrad Henkel on the occasion of his 70th birthday. 211