Oral Hygiene Index Simplified (OHI-S)

Dental Indices

• A dental index is an objective mathematical description of a disease or condition based on carefully determined criteria under specified circumstances.
• Properties of an index:
  • Validity: accurately reflects the extent or degree of the disease or condition.
  • Reliability: gives the same results with limited tolerance each time it is applied.
• Importance of an index: used to compare oral health status of a population following intervention and treatment.

Criteria for Selecting an Index

• Choose an index that addresses specific information of interest.
• The index should be suitable for the population.
• Choose an index that provides valid estimates of disease in the population.

Reasons for Developing New Indices

• To compare oral health status of a population following intervention or treatment.
• Population shifts and changes in disease experience.

Types of Dental Indices

• Caries indices:
  • DMF (Decay, Missing and Filled Index)
  • UTN (Unmet Restorative Needs)
  • RCI (Root Caries Index)
• Plaque and oral hygiene indices:
  • Oral Hygiene Index Simplified (OHI-S)
• Indices of periodontal health:
  • Russell's Periodontal Index (RPI)
  • Gingival Index of Loe and Silness
  • NIDR Gingival Index
  • Community Periodontal Index of Treatment Needs (CPITN)

Oral Hygiene Index Simplified (OHI-S)

• Measures plaque and calculus in 2 components:
  • Debris Index
  • Calculus Index
• Scores are added to have a single score.
• Index teeth: 16 bu, 11 la, 26 bu, 46 li, 31 la, 36 li.

Russell's Periodontal Index (RPI)

• Assigns a numeric score to each tooth in the mouth and takes an average of these values for a Periodontal Index score.
• Index teeth: 16, 21, 24, 44, 41, 36.
• Range of Russell score: 0 (no inflammation or disease evident) to 8 (advanced destruction with loss of masticatory function).

Gingival Index of Loe and Silness

• Evaluates gingival health.
• Uses the cervico-enamel junction (CEJ) as a reference point and a special periodontal probe, the National Institute for Dental Research (NIDR) probe.
• Measures loss of attachment as the sole indicator of periodontal health and disease.
• Scoring is on a scale of 0 to 3.

Community Periodontal Index of Treatment Needs (CPITN)

• Designed for epidemiologic surveys of periodontal health.
• Uses the CPITN-E probe and 10 index teeth that represent 6 segments of the mouth.
• Assesses pockets, bleeding, and plaque retentive factors (calculus and overhanging restorations).
• Designed to assess periodontal treatment needs rather than periodontal status.