This paper is the transcription of the course of Dr. Jens Pindborg, from Denmark, on the Ateneo Argentino de OdontologÃa, November 1988. The author provides current information on AIDS, epidemiologic factors, etiology, clinical and oral manifestations, associated diseases and treatment. Special emphasis are made in candidiasis lesions, gingival disease, oral viral Hairy leukoplakia and Kaposi's sarcoma.