Fig. (3) Mean Canary Numbers (CNs) for ICDAS II Groupings and clinical situation. Panels A and B). Mean Canary Numbers from all smooth (A) and occlusal (B) surface scans by ICDAS II Grouping: 0 (healthy), 1-2 (early caries), 3-4 (moderate caries), 5-6 (advanced caries). Single asterisk (*) indicates statistical significance (P<0.0083) between 0 (healthy) and all other groups. Double asterisk indicates statistical significance (P<0.0083) between the 1-2 (early caries) and the 5-6 (advanced caries) groups. Panels C and D). Mean Canary Numbers from all smooth (C) and occlusal (D) surface scans by clinical situation. Asterisk (*) indicates statistical significance (P<0.004) between sound and each of the other groups. “N” indicates the total number of scanned surfaces used in the calculation of each mean. Error bars represent the SEM.