In the Root Caries Index, the numerator consists of which surfaces?

• A. Decayed root surfaces only
• B. Filled root surfaces only
• C. Decayed and filled root surfaces
• D. All root surfaces including sound

Answer: (C)

Root caries experience is captured by counting surfaces that have been affected by decay, whether currently decayed or previously decayed and filled. So the numerator includes root surfaces that are decayed or have been restored due to root caries. This reflects evidence of caries activity as it has occurred in the past or is present now. Surfaces that are sound aren’t included in the numerator because they show no caries experience. The denominator, by contrast, accounts for all root surfaces at risk (including sound ones), so the ratio expresses the proportion of surfaces with caries experience out of all surfaces available.