Oral diagnosis and treatment planning: part 2. Dental caries and assessment of risk.

Dental caries or tooth decay may be defined as a dynamic process causing progressive destruction of hard tooth substance (enamel, dentine and cementum) involving demineralisation of the inorganic portion of the tooth, and dissolution of the organic portion. The onset and progression of carious lesions involves multiple host, micro-organism and substrate factors interacting in a continuous flux. The diagnosis of initial lesions remains a challenge for practitioners and, despite numerous studies, the assessment of future caries risk is still based largely on a patient's past caries experience. If caries is allowed to progress then pulpitis will occur, which may result in subsequent pulpal necrosis and lead to a local periapical and perhaps a systemic infection.