Oral Hygiene Index
Oral Hygiene Index-Simplified (OHI-S) · Also known as: OHI-S, simplified oral hygiene index, debris index, calculus index
The Oral Hygiene Index-Simplified (OHI-S) is a rapid, non-invasive assessment tool that evaluates the amount of plaque (debris) and calculus on tooth surfaces. Developed by Greene and Vermillion in 1964, it comprises two subscales: the Debris Index-Simplified (DI-S) measuring soft deposits and the Calculus Index-Simplified (CI-S) measuring hard deposits. The OHI-S is widely used in dental research, public health surveys, and clinical practice to assess oral hygiene status and evaluate the effectiveness of preventive interventions.
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When to use it
Use the OHI-S for rapid screening in clinical practice, baseline assessment before preventive education, and evaluation of the effectiveness of oral hygiene interventions. It is ideal for large-scale surveys where quick assessment is essential. Assume teeth are not heavily stained (extrinsic stains may obscure debris assessment). Prefer OHI-S when a simple, reproducible measure is needed; use more detailed plaque indices (e.g., Plaque Index) for detailed assessment of plaque microbiology or when individual tooth-surface analysis is critical.
Strengths & limitations
- Simple, quick to administer (typically 2–5 minutes) without requiring specialized equipment or dyes
- Standardized scoring system enabling comparison across individuals and populations
- Non-invasive visual assessment without patient discomfort
- Dual assessment of debris and calculus provides a comprehensive view of oral hygiene and mineralization
- Well-validated in numerous epidemiological studies and clinical trials
- Examiner subjectivity in assessing coverage percentages and distinguishing debris from extrinsic stains
- Visible plaque only; does not capture subgingival plaque or early biofilm formation not visible to the eye
- Index teeth may not represent overall oral hygiene if other areas have significantly different levels of deposits
- Cannot distinguish between different types of debris (food particles vs. bacterial plaque) or pathogenicity of biofilm
- Extrinsic stains from tobacco, coffee, or dietary substances can be mistaken for debris
Frequently asked
Can OHI-S be used to assess plaque microbiology or predict caries risk?
No. OHI-S is a visual assessment of debris and calculus quantity, not microbial composition or pathogenicity. It does not directly predict caries or periodontal disease risk; it indicates the level of oral cleanliness. Combining OHI-S with other risk indicators (dietary habits, fluoride exposure) provides better prediction.
How should extrinsic stains be handled during OHI-S assessment?
Extrinsic stains from tobacco, coffee, or dietary sources are not counted as debris. Use visual judgement and, if uncertain, gently rinse the surface with air-water spray to distinguish stains from actual deposits. Document if staining limits visibility.
Should subgingival calculus be included in the OHI-S score?
Yes, the Calculus Index-Simplified explicitly includes subgingival calculus when visible. Use light explorer pressure to gently lift the gingival margin and assess subgingival deposits without causing tissue trauma.
How does OHI-S compare to other plaque indices like the Plaque Index (PI)?
OHI-S is quick and assesses visible debris and calculus without dyes or probing. The Plaque Index (Silness and Löe) uses dye disclosure to identify plaque on all surfaces and is more detailed. Choose OHI-S for rapid screening; use PI for research requiring detailed plaque documentation.
Sources
- Greene, J. C., & Vermillion, J. R. (1964). The simplified oral hygiene index. Journal of the American Dental Association, 68(1), 7-13. DOI: 10.14219/jada.archive.1964.0034 ↗
- Vermillion, J. R., Arbuckle, G. B., & Spolsky, V. W. (1974). A comparison of the effectiveness of mechanical and chemotherapeutic plaque removal. Journal of the American Dental Association, 88(4), 862-865. link ↗
- Löe, H. (1967). The gingival index, the plaque index and the retention index systems. Journal of Periodontology, 38(6), 610-616. DOI: 10.1902/jop.1967.38.6.610 ↗
How to cite this page
ScholarGate. (2026, June 3). Oral Hygiene Index-Simplified (OHI-S). ScholarGate. https://scholargate.app/en/dentistry/oral-hygiene-index
Which method?
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