Numerous grading systems exist for the quantification of tooth wear, each unfortunately with its own particular shortcomings. In this dissertation a new and comprehensive tooth wear evaluation system is described. In it, the existing terminology is adapted to distinguish among mechanical-intrinsic (formerly attrition), mechanical-extrinsic (formerly abrasion), chemical-intrinsic (formerly erosion) and chemical-extrinsic (formerly erosion). In order to indicate the degree of wear, the terms mild, moderate, severe and extreme are used. On the basis of previous systems, 3 gradings scales were developed and tested for reliability for use in the dentist’s clinic, on dental casts and on intra-oral photographs. The grading scales were shown to be reliably applicable intra-orally, on the dental casts and on intra-oral photographs, particularly on occlusal/incisal surfaces. The findings of this research have resulted in the development of a modular Tooth Wear Evaluation System (TWES) in order to quantify, qualify, monitor and establish the likely causes of tooth wear. The evaluation system can also be used to determine management/treatment options.