What role does saliva play in dental health?

Saliva plays a crucial role in maintaining dental health, primarily through its ability to help neutralise acids in the oral cavity that are produced by bacteria during the digestion of sugars. This neutralisation is essential because a more acidic environment can lead to the demineralisation of tooth enamel, ultimately resulting in tooth decay and caries. Saliva contains bicarbonate, which acts to buffer these acids, thereby protecting the teeth and maintaining a balanced pH level in the mouth. Additionally, saliva provides essential minerals like calcium and phosphate, which are important for the remineralisation of enamel, further contributing to oral health.

In contrast, the other options presented describe either negative effects associated with acidity or irrelevant functions of saliva. For example, while an increase in acidity can lead to dental erosion, saliva actually works to counter this effect. Promoting tooth decay is contrary to the protective functions of saliva, and reduced ability to taste does not properly reflect the primary role of saliva in dental health maintenance. Thus, option B accurately encapsulates the protective and neutralising properties of saliva against caries.