PREVENTIVE AND COMMUNITY DENTISTRY INDICES PREVENTIVE AND COMMUNITY DENTISTRY

DENTITION CHART Deciduous teeth

DENTITION CHART Permanent teeth

DENTAL INDICES An index is defined as a numerical value describing the relative status of a population on a graduated scale with a definite upper and lower limits designed to permit and facilitate comparison with other populations classified by the same criteria and methods.

IDEAL REQUIREMNTS OF AN INDEX Simple Clear Reproducible Quantifiable or measurable Acceptable High validity and reliability OR High sensitivity and specificity Valid means that the data measure something that truly exist accurately. Reliable means that if measurement are taken on a different occasion the same answer is obtained.

COMMONNLY USED INDICES IN DENTISTRY DMFT/dmft OHI-S CPITN Plaque index of Silness and Loe Gingival index of Silness and Loe

DMFT / dmft This index gives a total score of all the affected teeth and provides a caries experience score for an individual D = Decayed 1 M Missing F Filled

DMFT INDEX & SCORES D = Decayed = 1 M = Missing = 1 F = Filled = 1 Examples done for you Say if 44 pupils have 35 decayed 21 missing and 8 filled teeth then the average DMFT is D+M+F/ No of pupil = 1.45

ORAL HYGIENE INDEX - SIMPLIFIED One of the most popular indicators for determining oral hygiene status in epidemiologic study The OHI was developed in 1960 by Greene and Vermilion and a simplified version of the OHI called OHI-S was proposed in 1964 The OHI-S differ from the OHI in the number of tooth surface scored ( 6 rather than 12)

ORAL HYGIENE INDEX - SIMPLIFIED The OHI-S has 2 components The Debri score The Calculus score The term oral debri include plaque, materia alba and food remnants

Selection of tooth surfaces The six surfaces examined for the OHI-S are selected from the 4 posteriors and 2 anterior teeth In the posterior portion of the dentition, the buccal surface of the upper 1st molars (16, 26) and the lingual surface of the lower 1st molars (36,46) are examined In the anterior portion of the mouth, the labial surfaces of the upper right (11) and lower left central incisors (31) are examined 16 11 26 46 31 36

Criteria for classifying debris Score Criteria No debris or stain present 1 Soft debris covering not more than 1/3 of the tooth surface, or presence of extrinsic stain without other debris regardless of surface area covered 2 Soft debris covering more than 1/3 but not more than 2/3 of the exposed tooth surface 3 Soft debris covering more than 2/3 of the exposed tooth surface

CRITERIA FOR CLASSIFYING CALCULUS Scores Criteria No calculus present 1 Supragingival calculus covering not more than 1/3 of the exposed tooth surface 2 Supragingival calculus covering more than 1/3 but not more than 2/3 of the exposed tooth surface or the presence of individual flecks of subgingival calculus around the cervical portion of the tooth or both 3 Supragingival calculus covering more than 2/3 of the exposed tooth surface or a continuous heavy band of subgingival calculus around the cervial portion of the tooth or both

CALCULATING OHI-S Oral Hygiene Index (OHI-S) = D I + C I 6 In OHI-S the minimum score is 0 and the maximum score can be 6

ORAL HYGIENE INDEX-S Advantages: It takes less time to score. It is easy to score. It is useful in survey work Disadvantages: Results are biased The index is not sensitive. It is not ideal for clinical trials {Research}.

PLAQUE INDEX of SILNESS AND LOE Plaque Index (PI) was developed by silness and Loe to be used along with gingival index (GI) to help correlate plaque accumulation with gingival inflammation the same surfaces of the teeth are scored as in the GI and the same scoring system of 0 to 3 is used. This index is applied to longitudinal studies and clinical trials because it is very sensitive to small changes in the amount of dental plaque The principal difference between the Plaque Index and OHI-S is that the PI assesses only the thickness of plaque at the gingival margin rather than its coronal extent on the tooth surface area. It has been proved that measuring plaque thickness is more valid than measuring its coronal extent.

CRITERIA FOR PLAQUE INDEX Score Criteria No plaque in gingival area 1 Film of plaque adhering to free gingival margin and adjacent area of tooth, plaque may be noticed by running a probe across tooth surface 2 Moderate accumulation of soft deposits within gingival pocket, on gingival margin, and or on adjacent tooth surface, which can be seen by naked ey 3 Abundance of soft matter within gingival pocket and\or on gingival margin and adjacent tooth surface

GINGIVAL INDEX OF LOE AND SILNESS The most frequently used index for evaluating gingivitis is the Loe & Silness gingival index. With this index, it is possible to measure bleeding tendencies color, contour changes of the gingiva alternations in the consistency of tissue and the presence of ulcerations. Bleeding is the most important criterion of inflammation in this index; however, the distinction between normal {0} and mild inflammation {l} is based on visual appearance of the tissues The gingival condition around each tooth is examined, and a score for the mesial, distal, buccal, and lingual areas is recorded. If desired, the gingival index can also be used on only selected teeth in the mouth

GINGIVAL INDEX OF SILNESS AND LOE Score Criteria Normal gingival 1 Mild inflammation-slight change in color, slight edema, no bleeding on probing 2 Moderate – bleeding on probing 3 Severe inflammation, marked redness and edema ulceration, tendency toward spontaneous bleeding

SCORING FOR GINGIVAL INDEX The sums of scores from the four areas of each tooth are divided by the number of teeth examined to produce a gingival index for the individual. Because bleeding on probing can be scored more objectively than a visual assessment of change in color, from and consistency of gingival tissues, the intensity of probing with a blunt instrument must be carefully controlled. The basic intention of this index is not to assess the depth or extent of a pocket or to determine bone loss but only to evaluate the status of gingival health

CPITN INDEX 3 indicators of periodontal status are used for this assessment Presence or absence of gingival bleeding Supra or subgingival calculus Periodontal pockets-subdivided into shallow (4-5 mm) and deep (6mm or more)

CPITN probe A specially designed light weight probe with a 0.5-mm ball tip is used, bearing a black band between a 3.5 and 5.5 mm from the ball tip.

SEXTANT The mouth is divided into 6 sextant defined by the teeth number A sextant should be examined only if there are two or more teeth present and not indicated for extraction. When only 1 tooth remain in a sextant it shuld be included in the adjacent sextant Upper right posterior 18-14 Upper anterior 13-23 Upper left posterior 24-28 lower right posterior 44-48 Lower anterior 33-43 lower left posterior 38-34

TEETH TO BE EXAMINED For adults aged 20 years and over, the teeth to be examined are The 2 molars in each posterior sextant are paired for recording, and if one is missing, there is no replacement. If no index teeth or tooth is present in a sextant qualifying for examination, all the remainng teeth in that sextant are examined For young people up to the age of 19 years, only six teeth 16,11,26,36,31 and 46 are examined For children under 15 recording for pocket should not be attempted. ie., only bleeding and calculus should be considered If no index tooth is present in a sextant qualifying for examination, single fully erupted incisor or premolar may be substituted 17 16 11 26 27 47 46 31 36 37

SENSING GINGIVAL POCKET The sensing force used should be no more than 20 gms A practical test for establishing this force is to place the probe point under he thumb nail and press until blanching occurs For sensing sub gingival calculus, the lightest force that will allow movement of the probe ball point along the tooth surface should be used The depth of insertion read against the colour coding. Atleast 6 point on each tooth should be examined

EXAMINATION AND RECORDING Score Criteria 4 Pocket > 6 mm (black area of probe not visible 3 Pocket 4 or 5 mm (gingival margin situated on black area of probe 2 Calculus felt during probing but all the black area of the visible 1 Bleeding observed, directly or by using mouth mirror, after sensing Healthy

FURTHER READING Norman O. Harris ; Arden G. Christen Chapter 13 – Periodontal Disease – Risk Assessment and Evaluation in ‘Primary preventive dentistry’ 4th edition. World health Organisation; Extracts of Oral Health Methods and Indices (copies provided)

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