What is the purpose of using fluoride in treating root surface caries?

Fluoride plays a critical role in the treatment of root surface caries primarily by protecting dentine and cementum. The application of fluoride enhances the remineralization process, helping to restore minerals lost due to decay on these exposed tooth surfaces. Dentine, which is the tissue beneath the enamel, and cementum, which covers the root surface, are both susceptible to decay when exposed due to gum recession or other factors.

Fluoride helps to reinforce these tissues by forming a more acid-resistant mineral phase in the tooth structure. This not only aids in remineralizing the affected areas but also reduces the risk of further demineralization and cavities. While protecting enamel and other aspects might seem relevant, the targeted benefit in treating root caries is significantly aimed at dentine and cementum, where the cariogenic process is actively impacting the tooth.