The document discusses the Oral Hygiene Index (OHI) and its simplified version (OHI-S) as tools for assessing oral hygiene and the extent of periodontal disease. These indices quantify oral hygiene through the evaluation of debris and calculus on specific tooth segments and help in classifying different forms of periodontitis. It also details the clinical features and classifications of periodontitis, highlighting its impact on dental health and the importance of measurement in ongoing care.

1. ORAL HYGIENE INDEX (OHI)
ORAL HYGIENE INDEX SIMPLIFIED (OHI-S)
CLASSIFICATION & EXTENT OF PERIODONTITIS
ORAL HYGIENE INDEX (OHI)
ORAL HYGIENE INDEX SIMPLIFIED (OHI-S)
CLASSIFICATION & EXTENT OF PERIODONTITIS
Harshada shirsat
(IVTH BDS)
Harshada shirsat
(IVTH BDS)

2. WHAT ARE INDICES?
Dental index or indices are devices to find out the
incidence, prevalence and severity of the disease, based on
which preventive programs can be adopted.
An index is an expression of the clinical observation in a
numerical value. It helps to describe the status of the
individual or group with respect to a condition being
measured.
"A numerical value describing the relative status of a
population on a graduated scale with definite upper and
lower limits, which is designed to permit and facilitate
comparison with other populations classified by the same
criteria and methods”
- Russell A.L.

3. DEFINITION

4. ORAL HYGIENE INDEX (OHI)
(developed in 1960 by John C. Greene and Jack R.
Vermillion)
It was depicted as a sensitive, simple and rapid method for
assessing group or individual oral hygiene quantitatively.
Methodology:
The Oral Hygiene Index comprises of 2 components,
1) The Debris Index (DI)
2) The Calculus Index (CI).
Each segment is examined for debris or calculus.From
each segment one tooth is used for calculating the
individual index, for that particular segment. The tooth
used for the calculation must have the greatest area
covered by either debris or calculus.

5. Segment 1: Distal to the right
cuspid on the maxillary arch
Segment 2: Mesial to the right
and left first bicuspids on the
maxillary arch
Segment 3: Distal to the left
cuspid on the maxillary arch
Segment 4: Distal to the left
cuspid on the mandibular arch
Segment 5: Mesial to the right
and left first bicuspids on the
mandibular arch
Segment 6: Distal to the right
cuspid on the mandibular arch
.

6. Rules:
1. Only fully erupted permanent teeth are scored.
(occlusal or incisal surface has reached the occlusal
plane)
2. Third molars are not included.
3. The scoring for the buccal/labial and lingual surfaces is
based on the tooth in the designated segment that has
the greatest surface area of debris for the DI or
supragingival and subgingival calculus for the Ci.
Therefore, the buccal/labial score and the lingual score
for a segment need not be taken from the same tooth.

7. No 23 explorer (Shepherd’s hook)
Move the explorer along the buccal/ labial and lingual surface
and look for amount of debris collected on explorer.
Procedure:
• For the Debris Index,

8. A No. 23 explorer is used for estimating the amount of
supragingival and subgingival calculus.
• For the Calculus Index,
Supragingival Calculus
Denotes deposits usually white to yellowish brown in colour
occlusal to free gingival margin
Subgingival Calculus
Denotes deposits usually light brown to black in colour,apical to
free gingival margin

10. Calculation:
The buccal/labial and lingual scores are tabulated and totaled for
each segment and arch. The debris and calculus scores are
tabulated separately and the indices for each are calculated
independently.

12. SIMPLIFIED ORAL HYGIENE INDEX (OHI-S)
(developed in 1964 by John .C Greene and
Jack R. Vermillion.)
Why OHI-S was Needed?
Even though the Oral Hygiene Index was determined to be simple
and sensitive, it was time-consuming and required more decision
making.
The Simplified Oral Hygiene Index (OHI-S) differs from the Oral
Hygiene Index in,
• The number of tooth surfaces scored (6 rather than 12)
• The method of selecting the surface to be scored
• The scores, which can be obtained
However, the criteria and scoring for the tooth surfaces remain
the same.

14. Rules
•At least two of the six possible tooth surfaces must
have been examined.
•Third molars are included only if they are functional
•Natural teeth with full crown restorations and surfaces
reduced in height by caries or trauma are not scored.
•If an index tooth/ substitute cannot be scored,it is
marked with X in a box
Mouth mirror, No. 23 explorer (Shepherd's Hook)
Instruments Used-

15. The oral hygiene examination and scoring for the DI always should
precede the oral examination and scoring for the CI.

17. INTERPRETATION

19. For an individual score-
• Scores are calculated to one decimal place
For a group of individuals-
• The debris and calculus scores are obtained by calculating
the average of the individual scores.
• The group scores may be calculated to one or two decimal
places, depending on the sample size.
Uses of OHI-S Index :
• It has been widely used in studies of the epidemiology of
periodontal disease.
• It is useful in evaluation of dental health education programs
in public school systems.
• It is used in evaluating the cleansing efficiency of tooth
brushes.
• It is used to evaluate an individual's level of oral cleanliness

20. PERIODONTITIS
Periodontitis is defined as "an inflammatory disease of the
supporting tissues of the teeth caused by specific
microorganisms or groups of specific microorganisms,
resulting in progressive destruction of the periodontal
ligament and alveolar bone with increased probing depth
formation, recession, or both."
The clinical feature that distinguishes periodontitis from
gingivitis is the presence of clinically detectable attachment
loss as a result of inflammatory destruction of the periodontal
ligament and alveolar bone. This loss is often accompanied by
periodontal pocket formation.

21. AAP held an International Workshop for the Classification of
Periodontal Diseases in 1999
CLASSIFICATION
Classification of the different forms of periodontitis was simplified
to describe three general disease forms:
1) CHRONIC PERIODONTITIS
2) AGGRESSIVE PERIODONTITIS
3) PERIODONTITIS AS A MANIFESTATION OF SYSTEMIC
DISEASE

22. Chronic periodontitis may be further subclassified into
localized and generalized forms and characterized as mild,
moderate, or severe based on the common features described
previously and the following specific features:
• Localized form: <30% of teeth involved
• Generalized form: >30% of teeth involved
• Mild: 1 to 2 mm clinical attachment loss (CAL)
• Moderate: 3 to 4 mm clinical attachment loss (CAL)
• Severe: 5 mm or more clinical attachment loss (CAL)

23. Clinical Attachment Loss:
Is the measurement of distance from cemento-enamel
junction (CEJ) to the apical extent (depth) of periodontal sulcus
It involve two measurments-
1)pocket probing depth
2)gingival margin level

24. First, measure the pocket depth with periodontal Probe
Then, measure the distance from marginal gingiva to
the CEJ
• If the gingival margin level above the level of CEJ, then
assign a negative sign to the number (e.g., 1, -2, -3...)
• If the gingival margin level at the same level of CEJ,
then the number is ZERO
• If the gingival margin level below the level of CEJ, then
assign a positive sign to the number (e.g., +1. +2, +3....)
HOW TO MEASURE?
NOW WE ADD THE TWO NUMBERS TOGETHER, AND
THE RESULT IS THE CLINICAL ATTACHMENT LOSS

25. Examples:
• Periodontal pocket depth = 2 And Gingival margin level=+1
Clinical attachment loss = 2 + 1=3
• Periodontal pocket depth = 5 And Gingival margin level= -2
Clinical attachment loss = 5 - 2 = 3

26. The following characteristics are common to patients with
chronic periodontitis:
• Prevalent in adults but can occur in children
• Amount of destruction consistent with local factors
• Associated with a variable microbial pattern
• Subgingival calculus frequently found
• Slow-to-moderate rate of progression with possible periods o
rapid progression
• Possibly modified by or associated with the following:
Systemic diseases such as diabetes mellitus and human
immunodeficiency virus (HIV) infection
Local factors predisposing to periodontitis
Environmental factors such as cigarette smoking and
emotional stress

27. Thank You !!
Thank You !!