[Oral precancer and cancer].

We reviewed the concept of oral precancerous lesions, oral cancer, and the possibility of early diagnosis. With the keywords: premalignant oral lesions prevention, a search was performed over the past 10 years. Also clinical trials are searched from January 2011 until today with the keywords: oral cancer prevention AND dentistry. It is emphasized that there can be no significant changes related to the concept of precancerous lesions and cancer, and those relating to the early diagnosis. Despite the numerous described methods of screening, biopsy remains the most useful test, and therefore it is essential, mainly if we consider the new possibilities of molecular studies.