PERIODONTAL DISEASE INDEX (PDI)

PERIODONTAL DISEASE INDEX (PDI)



PERIODONTAL DISEASE INDEX (PDI)

The periodontal disease index (PDI) was developed by Sigurd P. Ramfjord in 1959.

Objective:
The following objective were incorporated into the design of the index,
 To assess the prevalence and severity of gingivitis and periodontitis within the individual dentitions and in population groups.
 To provide accurate recordings for clinical trials of preventive and therapeutic trials of preventive and therapeutic procedures in periodontics.

Components:
The Three Components are,
 Plaque component
 Calculus component
 Gingival & Periodontal Component

Scoring Methods:
Only six selected teeth are scored for assessment of the periodontal status of the mouth, however, for short term clinical trials and where a limited number of patients are available, one may concern all of the teeth in the mouth. The six selected index teeth are,
16-Maxillary right first molar.
21-Maxillary left central incisor.
24-maxilary left first premolar.
36-Mandibular left first molar.
41-Mandibular right central incisor.
44-Mandibular right first premolar.

PLAQUE COMPONENT OF THE PERIODONTAL DISEASE INDEX

The surfaces scored are the facial, lingual, mesial and distal.

Instruments Used:
Mouth Mirror and a dental explorer

Method:
Scoring of plaque is done after staining with Bismarck Brown solution. Bismarck brown solution is placed in a dappen dish and two Richmond cotton pellets are placed in the dish until they appear completely saturated with the solution. One cotton pellet is removed with a cotton plier and touched gently on to the lingual and buccal surfaces of the mandibular teeth. The second pellet is touched on to the palatal and buccal surface of the maxillary teeth. The occlusal surfaces are also rubbed with the pellet. The second pellet is touched on to the palatal and buccal surface of the maxillary teeth. The occlusal surfaces are also rubbed with the pellet. So the disclosing flows over all the surfaces of the teeth. The patient is then instructed to spit and rinse thoroughly twice. The scoring is then done, by noticing the stained surfaces.
 SHICK & ASH MODIFICATION OF PLAQUE CRITERIA.

CALCULUS COMPONENTS OF THE PERIODONTAL DISEASE INDEX
The alculus component of the periodontal Disease index (PDI) ASSESSES THE PRESENCE AND EXTENT OF CALCULUS ON THE FACIAL (Bucclal/labial) and lingual surfaces of the 6 index teeth.

Instruments Used:-
Mouth Mirror and a dental explorer.

Calculation:-
The Calculation score per tooth are totaled and then divided by the number of teeth examined to yield the calculus score person.
The calculus component of PDI also has a high degree of examiner reproducibility and also can be performed quickly.

Instrument Used:-
Mouth mirror and University of Michigan Number 0 probe.
The University of Michigan Number 0 probe is graduated at 3, 6 and 8mm. from the end making it necessary to estimate intervening measurement.

Method:-
The probe should be held with alight grasp the end of the probe should be placed against the enamel surface coronally to the margin of the gingival so that the angle formed by the working end of the probe and long axis of the crown of the tooth is approximately 450. Minimal force should be used to pass the probe in an apical direction maintaining contact with the tooth. The probe should always be pointed towards the apex of the tooth or the central axis in case of multirooted teeth.
The buccal measurements should be made at the middle of the buccal surfaces. The mesial measuring should be made of the buccal aspect of the interpromixat contact area with neighboring tooth present and the probe pointing in the direction of the long axis o the tooth to he scored.

COMMUNITY PERIODONTAL INDEX OF TREATMENT NEEDS (CPITN)
The Community periodontal index of Treatment Needs” (CPITN) was developed for the “Joint Working committee” of the “World Health Organization” and “Federation Dentaire International” and “Federation Dentaire international” (W.H.O/F.D.I) by jukka Ainamo, David Barmes, George Beagrie, Terry Cutress, Jean Martin, and Jennifer Sardo-infirri in 1982.

Advantages:-
 Simplicity
 Spped
 International uniformity.

Limitation:-
 Does not record the position of the gingival margin.
 Does not provide assessment of past periodontal breakdown.
 CPITN is not a diagnostic tool and should not be used for planning of specific clinical treatment for individual patients.

Procedure:-
The dentition is divided into sextants (sixths of the dentition) for assessment of periodontal treatment needs. Each sextant is given a score.

Examination Probe:-
The recommended periodontal probe for use with CPITN was first described by WHO (TRS 621-1978). This probe was designed for two purposes, namely measurement of pocket depth and detection of subgingival calculus. The CPITN probe is both thin in the handle and is of very light weight (5 gms) This probe is particularly designed for gentle manipulation of the often very sensitive soft tissues around the teeth.
The pocket depth is measured through color coding with a black mark starting at 3.5 mm and ending at 5.5 mm diameter that allows easy detection of subgingival calculus. This feature combined with the light probe weight facilitates the identification of the base of the pocket, thus decreasing the tendency for false reading by measurement.

Probing Procedure:-
A tooth is probed to determine pocket depth and to detect subgingival calusus and bleeding response. The probing force can be divided into a working component to determine pocket depth and sensing component – to detect subgingival calculus.
The probe is inserted between the tooth and the gingival calculus.
The probe is inserted between the tooth and the gingiva, and the sulcus depth or pocket depth is noted against the color code or measuring lines. The ball end of the probe should be kept in contact with the root surface.

Codes & Criteria:-
The appropriate code for each sextant is determined with respect to the following criteria. The codes are listed in descending order of severity as follows:-

INDICES USED FOR ASSESSMENT:

Decayed- MISSING – FILLED TEETH INDEX (DMFT INDEX)

Advantages:-
 Simple
 Rapid
 Versatile
 Universally accepted and applicable measurement that has been used widely for several decades.

Procedure:-
The DMFT index is applied only to permanent teeth. It is composed of three components,
D- Used to describe decayed teeth.
M- Used to describe missing teeth due to caries.
F- Used to describe teeth that have been previously filled due to caries.

Instruments used:-
Primary tooth retained with the permanent successor erupted. The permanent toth is evaluated since a primary tooth is never included in this index.

Principle and rules in recording DMFT:-
 No tooth must be counted more than once. It is either decayed, missing, filled or sound.
 Decayed, missing, and filled teeth should be recorded separately since the components of DMF are of great interest.
 When counting the number of decayed teeth, also include those teeth, which have restorations with recurrent decay.
 A Tooth may have several restorations but it is counted as one tooth.
 A tooth is considered to be erupted when the occlusal surface or incisal edge is totally exposed or can be exposed by gently reflecting the overlying gingival tissue with the mirror or explorer.
 A tooth is considered to be present even though the crown has been destroyed and only the roots are left.

Calculation of the index:-
The maximum number for an individual DMFT score is 28 or 32, if the third molars are included.
A) Individual DMFT-
Total each component, i.e. D, M, & F separately, then, total D + M + F = DMF
For Example, a DMFT score of 3+2+5=10 for an individual means that 3 teeth are decayed, 2 teeth are missing, and 5 teeth have fillings. Furthermore, it also means that 18 (i.e. 28-10=18) teeth are intact.

B) Group Average:-
Total the D, M AND F for each individual. Then, divide the total DMF by the number of individuals in the group.
Average DMFT = Total DMF/ Total number of the subject examined.

Limitations Of DMFT Index:-
 DMFT index can be invalid in older adults because teeth can become last for reasons other than caries.
 DMFT index can be misleading in children whose teeth have been lost due to orthodontic reasons.
 DMFT index is of little use in studies of root caries.

DECAYED-MISSING FILLED TOOTH SURFACES INDEX (DMFS)

Procedure:-
The DMFS index is applied only to permanent teeth surfaces. It is composed of three components,
D- Used to describe decayed teeth surfaces.
M-Used to describe missing teeth surfaces due to caries.
F-Used to describe teeth surfaces that have been previously filled due to caries.

Advantages:-
The DMFS index is more sensitive and is usually the index of choice in a clinical trial of a caries- preventive agent.

Limitation:-
 A DMFS examination takes longer,
 Is more likely to produce inconsistencies in diagnosis.
 May require the use of radiographs to be fully accurate.

Instruments Used:-
 Mouth Mirror
 Explorer

The Surfaces examined are:-
 For posterior Teeth: Five Surfaces: Facial, Lingual, mesial, distal and occlusal.
 For anterior teeth: Four surfaces: Facial, Lingual, mesial, and distal.

Calculation of DMFS index:-
If 28 teeth are examined (i.e. third molars are excluded)
26 posterior teeth (16X5) = 80 surfaces
12 anterior teeth (12X4) = 48 surfaces
Total = 128 Surfaces
If third molars are included (4X5) = 20 surfaces
Total = 148 surfaces
The principle, rules, criteria and calculation for DMFS index is the same as that for DMFT index.

CARIES INDICES FOR PRIMARY:-

The Def index was described by Gruebbel A.O. in 1944, as an equivalent index to DMF index, or measuring dental caries in primary dentition.

Calculation of Def index:-
For deciduous or primary teeth, the maximum deft score for an individual would be 20 and the maximum score for the ‘defs’ will be 88 since primary dentition has a maximum of 20 teeth.

ROOT CARIES INDEX:-
The root caries index (RCI) was developed by Ralph V Katz in 1979, to make the simple prevalence measures for root caries more specific by including the concept of teeth or risk for root caries.
RCI is based on the requirement that gingival recession must occur before root surface lesions can be. Teeth with gingival recession represent the true intraoral unit at risk, thus preventing an underestimation of the attack rate of root caries. Therefore, only teeth with gingival recession are examined.

Procedure:-
To obtain the RCI, each of the four surfaces, the mesial, distal, buccal (labial), and lingual, of a root are examined for single tooth. All teeth are examined in both the lower and upper arch. For teeth with multiple roots (i.e. two or three roots) and extreme recession, it is the suggested rule that when multiple types of root surfaces are exposed, the most severely affected root surface be occurrence is judged to be rare. The root surfaces are characterized and recorded as
R-M+ Recession present, Surface normal or sound
R-D = Recession present, with a decayed root
R-F= Recession present, with a filled root surface
No-R = No Association with gingival recession
M = Root Surfaces characterized as missing.

A designation of missing (M) is made for the whole tooth and not for a single surface. Therefore, once a tooth is observed to be missing. A judgment of no recession (No-R) is made if the cement enamel junction (CEJ) cannot be observed. In addition, if calculus is present in the absence of any other findings on a recessed root surface, a judgment of sound (R-N) is made on the assumption that decay is not found underneath the band of calculus.
The data collected is entered on a format for each tooth examined as given below,
The column represent four surfaces: M- mesial, D-Distal, B-Buccal, L-lingual, the rows represent the conditions that could occur on the surfaces.
The root carries index is calculated for an individual using the formula:
RCI Score = (R-D) + (R-F) / (R-D) + (R-F) + (R-N) x 100