university collegium; a profession based on scientific principles. This evolution has coincided with a remarkable improvement in dental public health in countries with strong academic ~ dental programs. Most people in industrialised countries now can expect to retain a functional dentition throughout life. Caries rates are markedly reduced in great part due to fluoride use, one of the most cost-effective public-health measures lmown. Periodontal diseases can be minimised with excellent oral hygiene and chemotherapeutic agents. However, there is more to do. Routine dental care (tooth, gingival) is expensive. For many poor people in industrialised countries, and most people in other regions of the world, there is no access to care and dental health showed little improveA street dentist in the Far East ment in the past century. In many countries, care for dental and oral tissues, and general medical care are separated. Oral medical (stomatological) disorders are commonly neglected because neither dentists nor physicians take responsibility for them. Comprehensive care for dental and oral diseases is generally not a part of health-care planning, nor a right of, society in the same way that other medical care is viewed. Rather, it is perceived as a luxury. Dentistry is also experiencing a struggle for identity, torn between not having broken free of its technical and proprietary roots (eg, current US emphasis on aesthetic dentistry) and becoming more biomedical and academic in outlook. These directional pulls are mutually exclusive and will lead ultimately to a fracture of the existing profession. In 25 years, health care for the mouth will be two-tiered, perhaps like the situation for ocular tissues in which ophthalmology and optometry give different levels of care. The forces driving this change will be societal, economic, and biological. In industrialised societies the internet has made health consumers better and more easily informed. Knowledgeable people will recognise that diseases in the mouth are similar and related to pathologies elsewhere. Patients will realise that the forces that separate dentistry from the rest of medicine are historical, political, and inappropriate. Pressure will develop to include the mouth in health-care programmes. Many more people will have access to care. The cost to society of managing the resulting expanded patient population will be prohibitive if care is provided by the traditional university-trained, but technically oriented, dentists. There will be economic pressure to change the way dental care is delivered. Prevention will be stressed, with caries and periodontal diseases managed like other infectious diseases. Planners will rediscover earlier research studies showing that trained dental auxiliaries are able to provide quality primary dental care, including simple dental restorations. Expanded roles for allied dental workers will allow cost-effecrive oral care, even in non-industrialised countries. The need for oral-health-care providers at the doctoral level will decrease, and their focus will shift to complicated dental and oral surgical procedures, stomatological disorders, and supervising a staff of trained and prevention-oriented primary providers. Medical training will incorporate care of the mouth, and oral health will be integrated fully with general health. Although biological factors have had an effect on dental practice (eg, antibiotics, AIDS), major cell and molecular biological advances have not greatly influenced care of the mouth. However, many topflight non-dentally-trained basic scientists are being recruited to study fundamental biological questions using traditionally dental models, such as tooth development and oral microbial colonisation. The separation from medicine that plagues clinical dentistry does not exist to the same degree in the biomedical sciences. Indeed, the connection between the dental research community and the biomedical research community is one squrce of the tension existing within dentistry. Forefront biomedical technologies are being applied to dental and oral diseases. For example, emerging principles of tissue engineering are being used to regenerate periodontal bone using biodegradable substrates seeded with growth factors. Viral-mediated gene transfer is being tested as a way to repair irradiationdamaged salivary glands and to redesign glands to have endocrine functions. A monoclonal antibody generated in transgenic plants can protect patients against oral streptococci. In the next 100 years, dramatic reduction in the common dental diseases that have been a source of pain and misery to people throughout history. A biotechnological breakthrough (eg, a mouthrinse with peptides generated by combinatorial chemistry) will disrupt dental plaque and be the fluoride of the new century. I expect that my successor writing in The Lancet's 21st century celebratory issue will state that dentistry has attained the crowning achievement for a health profession; virtually eliminating the need for itself by 2099! there will be a worldwide