Mean plaque score at the gingival margin across examined sites — 0 to 3
Enter how many sites scored at each grade (usually four sites per tooth).
Grade 0 — no plaque
Grade 1 — plaque film, detected only by running a probe
Grade 2 — moderate plaque, visible to the naked eye
Grade 3 — abundant plaque at the margin / in the pocket
Enter a site count for every grade (use 0 where none)
Evidence
Original publication
Silness J, Löe H. Periodontal disease in pregnancy. II. Correlation between oral hygiene and periodontal condition. Described the Plaque Index (PlI): each of four surfaces per tooth is scored 0–3 for the amount of plaque at the gingival margin, assessed with a probe; the case score is the mean of all sites.
Acta Odontologica Scandinavica, 1964
Open source
Guideline
The Plaque Index is the companion measure to the Gingival Index and is used to relate oral-hygiene status to gingival inflammation and to monitor plaque-control instruction over time.
Last reviewed: 2026-09
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MedScore is an educational and clinical decision-support tool. It does not provide a diagnosis, a treatment, or a drug-dosing recommendation, and it does not replace clinical judgement or local guidelines. Confirm every result against the original source before acting on it. The treating clinician remains responsible for all decisions.