In order to use the ICDAS criteria the following conditions are essential to enable examiners to assess each of the caries codes accurately: overhead operating light; cleaned teeth and compressed air.  Since caries forms in areas of plaque stagnation it is essential that the teeth are cleaned with at least a toothbrush and floss before conducting an examination using the ICDAS criteria.

Those teaching ICDAS should at least be familiar with the ICDAS e-learning material which is available for free use from here ICDAS.org website

Explanation to the table

Column 1: Relationship between scores 0-6 in the table and histological depth

Scores  Histological depth 

0  No enamel demineralization or a narrow surface zone of opacity (edge phenomenon) 

1  Enamel demineralization limited to the outer 50% of the enamel layer

2  Demineralization involving between 50% of the enamel and 1/3 of the dentine

3  Demineralization involving the middle 1/3 of the dentine, clinically microcavitated

4 (3)  Demineralization involving the middle 1/3 of the dentine, clinically shadowed

5 (4)  Demineralization involving the inner 1/3 of dentine± into the pulp, clinically cavitated but the cavitation < ½ the surface

6 (4)  Demineralization involving the inner 1/3 of dentine± into the pulp, clinically cavitated but the cavitation > ½ the surface

See table at the end of this page      Modified from Ekstrand et al., 1997

Column 2: Terms of increasing severity stages of caries for lay persons

Column 3: Terms for the visual apperance for increasing severity stages of caries for professionals

Column 4 Related scores to coulmn 3

Column 5: Activity assessment posibilities for the scores in column 4 and thus also columns 3 and 2. +=active lesion;- =arrested lesion

Column 6: Scores for radiographical classification of lesion severity:

  0=no radiolucency 

  1= radiolucency in outer ½ of the enamel

  2= radiolucency in inner ½ of the enamel± EDJ 

  3= radiolucency limited to the outer 1/3 of dentine

  4= radiolucency reaching the middle 1/3 of dentine

  5= radiolucency reaching the inner 1/3 of dentine, clinically cavitated

  6= radiolucency into the pulp, clinically cavitated

Column 7: Scores for Fibre-optic translumination (FOTI); classification of lesion severity: Proximal and occlusal

  0= no shadow or stained area

  1= Lesion stays the same width when transilluminated/Thin grey shadow into enamel when transilluminated

  2= Wide grey shadow into enamel when transilluminated 

  3= Wide grey shadow into enamel with no evidence of dentine shadow

  4= Orange/brown or bluish/black shadow < 2mm in width

  5= Shadow as described above and/or transillumination light is blocked > 2mm in width

  6= Large area of frank cavitation with likely pulpal involvement

Column 8: Risk assessment:h=high, m=medium, l=low

Column 9: PTO = Preventive treatment option; OTO = Operative treatment option

Column 10: p = progressing; a = arrested; r = regressing