Plaque Index Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 27, 2026
Disclaimer: This calculator is provided for informational and educational purposes only and does not constitute financial, medical, legal, or other professional advice. Always consult a qualified professional before making decisions based on these results.
Plaque Index Calculator
The Silness-Loe Plaque Index is a standard clinical and research tool for quantifying plaque buildup at the gumline, scoring individual tooth surfaces on a 0-3 scale and averaging across all surfaces examined.
Plaque Index = Average of all surface scores (0-3 scale each)
Scoring Scale
| Score | Description |
|---|---|
| 0 | No plaque |
| 1 | Thin film of plaque, only detected by running a probe across the surface |
| 2 | Moderate plaque visible to the naked eye |
| 3 | Heavy plaque accumulation filling the space between tooth and gum |
Example
Surface scores of 0, 1, 1, 2, 0, 1:
Average = (0+1+1+2+0+1)/6 = 0.833 (good oral hygiene)
This index is frequently used in dental research to compare brushing techniques, oral hygiene products, or track improvement over time in a clinical setting. This tool is educational only and does not replace a professional dental exam.