Fluoride and Dental Erosion

While dental erosion, like caries, is a mineral process, the erosion process follows a somewhat different pathway.38,50 There is little possibility of reversal, as erosive acids are able to overwhelm the protective pellicle layer and soften outer surfaces of the tooth; these softened surfaces can then be lost to abrasive forces, resulting in permanent and irreversible loss of tooth structure (Figure 12).

Figure 12.
Diagram showing dental erosion.
Dental Erosion. Erosion processes result in permanent loss of surface mineral structure.

It is well accepted that fluoride helps keep teeth strong. However, recent studies have demonstrated that all fluorides are not alike with their ability to help prevent dental erosion. While there would likely be a greater incidence of dental erosion in the absence of fluoride, the data suggest that most fluorides do not provide a high level of benefit against the increasing levels of challenge teeth are facing in today’s environment. In spite of the fact that almost 100% of the world’s toothpastes contain fluoride, the incidence and prevalence of dental erosion both appear to be on the rise. These data suggest many fluoride products may not be sufficiently effective to protect teeth against erosive acid challenges. However, one of the currently used sources of fluoride, stannous fluoride (SnF2) (Figure 13), has been demonstrated in a broad range of studies to be unique in its ability to help prevent the initiation and progression of dental erosion. These include both laboratory51-54 and human in situ erosion clinical studies.55-60 Different from other sources of fluoride used, stannous fluoride deposits a retentive, acid resistant barrier layer onto exposed tooth surfaces that is protective against both the initiation and progression of dental erosion (Figure 14).61

Figure 13.
Diagram showing stannous fluoride molecule.
Stannous fluoride (SnF2) is unique among the sources of fluoride routinely used for toothpaste formulations.
Figure 14.
Diagram showing enamel windows exposed to erosion cycling.
SnF2 helps prevent erosion by depositing an acid resistant barrier layer on exposed tooth surfaces, thus preventing the initiation and progression of irreversible damage.
Adapted from Faller; Cosmetics & Toiletries, 2012.62