INDICES

Index is a graduated scale having upper and lower limits, with scores on the scale corresponding to specific criteria which is designed to permit and facilitate comparison with other population classified by same criteria and methods- Russel AL
Ideal requisites of an Index:

Simplicity
Objectivity
Validity
Reliability
Acceptability
Quantifiability

1.ORAL HYGIENE INDEX:

Proposed by John C Green & Jack R Vermillion in 1960
Consist of 2 components: a) Debris index (DI)
b) Calculus index (CI)

2.OHI SIMPLIFIED:

By J C Green, J R Vermillion, 1964
Only fully erupted permanent teeth are scored.

Natural teeth with full crown restorations and surfaces reduced in height by caries or trauma are not scored.
An alternative tooth is then examined

3. PLAQUE INDEX:

Silness & Loe in 1964
Surfaces examined: D M L B
Teeth examined: 16,36,12,32,44,24

4. GINGIVAL INDEX:

Loe H & Silness J in 1963
Most widely used index
Surfaces examined: M L D F
Only quantitative changes are assessed
Tooth examined- 16,12,24,36,32,44
A blunt periodontal probe is used to assess the bleeding potential of the tissues.