It is defined as physiologic wearing away of tooth as a result of tooth to tooth contact a as in mastication. Everyone wears down their teeth in one way or another during a lifetime, thus everyone suffers at least some attrition.
It is defined as pathological wearing of tooth substance, through some abnormal mechanical process, like from misuse of toothpaste on virtually any surface exposed to toothbrush bristles or toothpaste.
It is a wedge shaped defect limited to cervical area of teeth. It may resemble cervical abrasion or erosion. There is loss of cervical tooth structure secondary to repeated flexure of tooth caused by occlusal stress. It is thought that lateral occlusal forces bend the tooth with tensile stress concentrated in cervical fulcrum area, leading to disruption of enamel and dentin bonds. Once damaged the area may be enlarged secondary by abrasion, attrition, erosion.