It has been established that a host must be present for caries to develop. Here, three host factors - the tooth, saliva, and the oral cavity’s immune response - are introduced, and their roles in the caries process are explained.

Clinical Significance Snapshots

In managing patients at risk of dental caries, how should I approach managing ‘host’ factors involved in the caries process?

The two tissues of the host affected by dental caries are the enamel and the dentin. In young persons, enamel is the main tissue that is affected, as no dentin is exposed directly to the oral cavity. Later in life, when gingival recession has exposed the roots of the teeth, dentin becomes exposed to the oral cavity. So, as a first line of defense, it is important to protect the enamel and try to prevent gingival recession.

First, saliva bathes all tissues exposed to the oral cavity. In healthy individuals, there is an adequate flow (quantity) of this fluid that helps flush away cariogenic foods, and the fluid is saturated with respect to calcium, which reduces demineralization and encourages remineralization (quality). The effects of medication are the most common problem that leads to a lack of saliva. Many prescription and OTC medicines, and some recreational drugs, reduce the flow of saliva and cause Xerostomia or dry mouth. In cases of dry mouth, caries and erosion are highly prevalent. It is important that the dental professional checks for adequate quantity and quality of saliva, and consults with the patient’s physician if necessary.

Second, the hard tissues should be protected by a plentiful exposure to fluoride. Brushing twice daily with a fluoride toothpaste is clinically proven to reduce dental caries by more than 50%. Fluoride can also be applied in the office or at home by the use of rinses, gels, and similar products. The roots can be protected from risk of root caries by preventing gingival recession first and foremost, and by practicing safe and gentle oral hygiene methods. If roots are exposed, they can also be treated with fluoride compounds, and the patient should be advised of the increased risk of dental caries and the need for thorough oral hygiene of the exposed root surfaces.