Facial surfaces Occlusal/oral surfaces
0 No erosion. Surface with a smooth, silky glazed appearance, absence of developmental ridges possible No erosion. Surface with a smooth, silky-glazed appearance. Absence of developmental ridges possible
1 Loss of surface enamel. Intact enamel found cervical to the lesion concavity in enamel, the width of which clearly exceeding its depth, thus, distinguishing it from toothbrush abrasion, undulating borders of the lesions are possible dentine is not involved Slight erosion, rounded cusps, edges of restorations rising above the level of adjacent tooth surface, grooves on occlusal aspects. Loss of surface enamel. Dentine is not involved
2 Involvement of dentine for less than one-half of the tooth surface Severe erosion, more pronounced signs than grade 1. Dentine is involved
3 Involvement of dentine for more than one-half of the tooth surface