Abstract
The aim of this article is to review the progress and current opinions of this problem. There are three different ways linking oral infection to secondary diseases.
These are metastatic infection, metastatic injury, and metastatic inflammation. The most frequent oral (dental) foci are the consequences of long time persistence of microbial plaque (caries, apical periodontitis, marginal periodontitis).
For exclusion of dental focal infection an evaluation of oral hygiene and appropriate motivation of patient with correct instruction in dental hygiene is necessary.