Table 1: Ordinal scoring system.

Score Surface Criterion
0 OI No loss of enamel surface characteristics
1 OI Loss of enamel surface characteristics
2 O
I
Enamel loss just exposing dentine <1/3 of the surface
Enamel loss just exposing dentine
3 O
I
Enamel loss just exposing dentine >1/3 of the surface
Enamel loss and substantial dental loss but no pulp exposure
4 O
I
Complete enamel loss, or pulp exposure or 20 dental exposure
Pulp exposure or 20 dental exposure

O=Occlusal; I=Incisal