Physical Wear – Abrasion, Attrition, Non-Carious Cervical Lesion

Abrasion is commonly associated with cervical region (gingival margin). This association has been linked to Non-Carious Cervical Lesion (NCCL), which are V-shape cavities seen running horizontally along the gingival margin of some teeth in some patients. Studies have shown that NCCL is created with horizontal brushing with commercial toothpastes.⁶ Toothbrushes without toothpaste do not create these lesions. There is no correlation between firmness of toothbrush or abrasive index and the size of the NCCL; however, the various shapes of NCCL are due to toothbrush filament deflection.⁶ The amount and direction of filament deflection is affected by stiffness, juxtaposition of teeth, contours of gingival and teeth, and pressure. However, NCCL can be exacerbated by demineralization by erosive agent. Tooth wear by attrition is the physical loss of mineralized tooth substance caused by tooth-to-tooth contact without the influence of any other factor, as can be seen in bruxism. This can also be exaggerated by demineralization from erosive agents. Thus, the four tooth wear types are interrelated in the mechanism of formation.

Figure 1. Abrasion

Figure 1. Abrasion

Figure 2. Attrition

Figure 2. Attrition