This part of ISO/TS 14569 specifies test methods for the assessment of resistance to wear of materials occurring on the occlusal surfaces of restorations, in or on natural teeth or on artificial teeth, as a result of physiological activity in the mouth. Some of the proposed methods include wear from foodstuff as well as, or only, wear by direct contact. The test methods shown in Table 1 are described. This part of ISO/TS 14569 is not applicable to phenomena such as the marginal degradation and loss of substance by chemical processes, swelling, splintering of edges, or wear from toothbrushing.