The objective of this proposal is to seek continued support for the development and operation of an interdisciplinary Center for Research in Oral Biology. The purpose of the Center is to assist in the national effort to reduce the toll of oral disease and to promote the general level of oral health. The Center seeks to develop and support meritorious and relevant research projects by creating an intellectual and physical environment conducive to optimal research productivity and collaboration, by providing opportunities for significant interaction among investigators with diverse backgrounds, and by encouraging the incorporation of relevant research findings into dental education, dental practice and the surrounding community. The Center strives to maintain a balance between basic biologic and clinical research, to increase the level of research effort in oral microbiology, especially as it pertains to the periodontal diseases, and to encourage research efforts in the School of Dentistry. During the upcoming grant period, emphasis will continue to be placed on analysis of mechanisms of tissue alteration in the periodontal diseases and in application of currently existing basic knowledge to the problems of diagnosis and management of these diseases. Other major components of the research program concern normal and abnormal connective tissue structure and metabolism, bone and calcification, keratinization, regulation of the antibody response, salivary secretion and the function of saliva in maintenance of oral health.