Abrasion, derived from the Latin verb abradere, nhrasi, ahrasum (to scrape off,), describes the wearing away of a substance or structure through mechanical processes, such as grinding, rubbing or scraping.
The clinical term dental abrasion or abrasio dentium is used to describe the pathological wearing away of dental hard tissue through abnormal mechanical processes involving foreign objects or substances repeatedly introduced in the mouth and contacting the teeth.
Depending on the etiology, the pattern of wear can be diffuse or localized. Based on the clinical observation of the frequent coincidence of smooth-surface and/or cervical abrasion and extensive oral hygiene, the latter has been incriminated to be a main etiological factor in dental abrasion .
Both patient factors and material factors have been found to influence the prevalence of abrasion. Patient factors include brushing technique, frequency of brushing, time spent on brushing, force applied during brushing, where on the dental arch brushing is started, etc.
Material factors refer to type of material, stiffness and end-rounding of toothbrush bristles, tufted sign of the brush, flexibility and length of the toothbrush grip, as well as abrasiveness, pH and amount of dentifrice used.
Abrasion on proximal tooth surfaces may be caused by extensive use of interdental cleaning devices such as tooth picks or interdental brushes, especially when they are inserted along with toothpaste or toothpowder.
Occupational abrasion, i.e. excessive tooth wear due to any professional cause such as abrasive dust at the work place, holding nails between the teeth biting thread, etc. are only rarely seen today.