They are progressive and slowly damage the tooth.
These lesions are defined as wear or loss of the hard dental tissue known as enamel and dentin.
Abfraction is a loss of tooth structure of variable size, observed as a deep, wedge-shaped cavity, with defined edges, near or at the level of the gum.
Abrasion refers to the loss of dental structure due to a mechanical cause. It is observed as lines or ridges on the tooth.
Erosion is evident damage to the dental structure. It is caused by chemical agents, specifically acids of external or internal origin.
The treatment of these injuries depends directly upon the type of injury, the origin, and the medical and dental history of each patient.