The present study sought to evaluate the characteristics of tooth wear in subjects with an acidic diet in relation to subjects with substantially different nutritional patterns. The evaluation included medieval skulls (group 1, n = 102, abrasive nutrition), study models of individuals living on an acidic diet (group 2, n = 100) and randomly selected subjects (group 3, n = 100, average Western diet). Wear was visually recorded on oral, vestibular and occlusal/incisal surfaces using quantitative and morphological criteria. The mean age was 42.3 +/- 15.3 yr in group 1, 40.9 +/- 11.2 yr in group 2 and 36.7 +/- 11.7 yr in group 3. Group 1 exhibited the most pronounced substance loss, followed by groups 2 and 3. On occlusal surfaces, cupping was common in group 1 followed by group 2, but was rare in group 3. An inverse relation was found for facets. On buccal surfaces, no substance loss was observed in group 1, whereas in group 2, 63% had at least one tooth with a buccal lesion compared to 8% in group 3. The occlusal substance loss observed in subjects exposed to acids may be interpreted as increased abrasion/demastication of acid-softened dental hard tissues. The occurrence of concavities on smooth surfaces appears to be significant for the diagnosis of dental erosion.