[Dental foci. Role, treatment and prophylaxis in patients at risk].

A dental focus usually is a localized chronic infection that under certain circumstances may result in severe local or systemic disease. The most important dental foci are periodontitis, periapical lesions, advanced carious lesions, nonvital pulp, partially impacted teeth and root tips. Local effects of dental foci particularly are processes that may come to expression because of a compromised immunological defence, such as osteoradionecrosis. Systemic effects are mainly caused by transient bacteraemia which can occur spontaneously out of dental foci or after manipulations such as brushing, flossing and dental treatment. Well known examples are infectious endocarditis, fever during chemotherapy and hematogenous infections of total joint prostheses. For all patients at risk (a.o. endocarditis, endoprosthesis, chemotherapy, radiotherapy) it is important that dental foci are treated. Because in most patients the risk factors are present lifelong, a healthy dentition and a healthy periodontium are the best way of prevention.