Although the dermatologist spends many years in preparation for practicing his specialty, most curricula do not include even one course in dentistry which points out the relationship of dentofacial variations or pathological conditions with the skin and mucous membranes. Van Studdiford, in 1953,1wrote on certain aspects of this subject, but there has been a paucity of such information in the dermatological literature. Some of the associations stressed in this paper are not found in standard dermatology textbooks. The scope of this paper will be limited to those conditions of the skin or mucous membranes which are caused from or associated with variations of the natural or artificial teeth or their supporting osseous structures. No attempt will be made to include the numerous pathological conditions of the soft tissue about the oral cavity which are not so related. Mandibular Prognathism Mandibular prognathism is a condition in which the