Key Differences Between Caries and Dental Erosion

Generalities can be confusing. Caries is often described as the loss of minerals by the direct action of acids on the teeth, and dental erosion is also defined in a similar way. While both statements are true, of primary importance is the type of acid, where the acid comes from and specific sites on the tooth surface to which these acids are directed. It is important to differentiate enamel damage due to caries vs. damage that results from dental erosion. Both the etiology and symptoms of these two processes differ significantly, as do the appropriate management strategies for each (Table 3).

One major difference between caries and dental erosion needs to be clearly understood. Caries is a process that begins with demineralization and, at early stages, can be reversed, either through the natural process of remineralization or through enhanced remineralization due to fluoride therapy. Dental erosion, on the other hand, is essentially a non-reversible process that results in permanent damage to the tooth structure.

Table 3. Key differences between caries and dental erosion.

Graphic of a tooth.Photo of cavities in teeth.Photo of tooth erosion.
Key ComparisonsCavitiesErosion
Type of processMineral ChangeMineral Loss
Tooth site(s) affectedEnamel & dentinEnamel & dentin
Primary causeBacterial acidsDietary acids
Primary site(s) of damageSubsurface, under plaqueExposed, plaque free surface
ConditionsExposure to weak acids for prolonged periods of time, usually at a pH above 4.0Repeated exposure to dietary or gastric acids, generally below pH 4.0, for short time periods
ResultSub-surface phenomenon with intact outer layer of enamelSurface softening leading to loss of surface mineral
Reversible?Reversible in early stagesIrreversible surface loss
Contributing factorsBuffering by saliva helps neutralize bacterial acidsSaliva and pellicle overwhelmed by dietary and gastric acids
Preferred therapeutic approachPrevention as well as reversal of early damagePrevention is critical for managing
Fluoride effectiveness------------------------
Sodium fluorideYesMinimal
Sodium monofluorophosphateYesMinimal
Stannous fluorideYesYes