C HAPTER 3 Epidemiology of Periodontal Diseases Copyright © 2014, 2007, 2001, 1996 by Saunders, an imprint of Elsevier Inc.

CHAPTER 3

Epidemiology of Periodontal Diseases

Copyright © 2014, 2007, 2001, 1996 by Saunders, an imprint of Elsevier Inc.

EPIDEMIOLOGY

Epidemiology is the study of health and disease and the factors associated with health and disease in human populations. Epidemiologic factors include heredity, biology, physical

environment, social environment, and personal behavior.

2 Copyright © 2014, 2007, 2001, 1996 by Saunders, an imprint of Elsevier Inc.

EPIDEMIOLOGY (CONT.)

Epidemiology measures the: Prevalence of disease—number of individuals or sites

with disease present in a given population at one time Incidence of disease—rate of occurrence of new

disease in a population over a given period Severity of disease—level and probability that a site will

become diseased Risk factors of disease—exposures, behaviors, and

characteristics associated with disease



Epidemiologic research differs from clinical research in that entire groups are the focus of the study, not individuals.



Epidemiologic research uses calculations to assess diseases in a population. Prevalence (P)

Divide the number of persons with the disease by the number of persons in the population.

P = number with disease ÷ number in the population

Incidence (I) Divide the number of new cases of the disease

by the number of persons at risk in the population.

I = number of new cases ÷ number of persons at risk



Common types of experimental designs used in epidemiologic research include: Cross-sectional studies Cohort studies Case-control studies



In relation to periodontal disease, epidemiologic research: Demonstrates how much of a population is affected by

periodontal disease. Describes the severity of the disease in a group of

individuals. Identifies characteristics or behaviors likely to be found

in persons with the disease.



The entire set of individuals within the population can be assessed, or a sample of the individuals can be assessed.

The ideal sample is when individuals are randomly selected.



Researchers define what constitutes gingival and periodontal disease by clinical assessment, using measurement scales known as indices (or indexes).



When evaluating a population, examiners should be calibrated or standardized. For example, all examiners should interpret a

4 mm probing depth the same way. Achieving 100% agreement among examiners at all

times is impossible, but, with training, examiners can agree most of the time.

This agreement is essential for the information collected to be meaningful; the clinician will know that the data were accurately interpreted.



Examining every human being in large epidemiologic studies is not possible; therefore representative samples are selected.

Ideally, results found in a sample should be able to be generalized to a significantly larger group of the population. This application of sample findings is referred to as a

generalization of results.



Epidemiologic data do not provide absolute values for a population.

Studies differ in their findings as a result of differences in population, examiners, or measuring scales.

Well-designed, well-run epidemiologic studies provide information that is distinct from information gained from clinical studies.

Epidemiologic data provide a general understanding of the disease occurring in patients.


REVIEW OF IMPORTANT INDICES

Several indices are used to evaluate the periodontal status of populations.

These indices include but are not limited to: Plaque debris indices Calculus indices Periodontal disease indices


PLAQUE DEBRIS INDICES

Plaque is an important quantity to define; it is the etiologic agent in periodontal disease.

Screening populations for the presence of plaque determines whether all of the people have plaque, how much plaque they have, and how it relates to other signs of disease.


PLAQUE INDEX OF SILNESS AND LÖE

Plaque Index of Silness and Löe (Pl I) The amount of plaque at the gingival margin

determines the score. The amount of plaque is tested by running a probe

across the gingival margin. The following criteria are used for scoring:

0 = Plaque free 1 = Plaque visible on the point of a probe 2 = Thin-to-moderate plaque 3 = Heavy plaque


PLAQUE INDEX OF SILNESS AND LÖE (CONT.)

These data can be evaluated by tooth, by groups of teeth, or by individuals in a population. Adding the scores for the measured surfaces on each

tooth and then dividing this number by the number of surfaces determines the “tooth score.”

Adding the tooth scores and then dividing this number by the number of teeth determines the “whole mouth score.”


SIMPLIFIED ORAL HYGIENE INDEXOF GREENE AND VERMILLION

Oral Hygiene Index (OHI-S) The simplified oral hygiene index has both a plaque

debris index (DI-S) and a calculus index (CI-S). Scores can provide a plaque DI-S or a CI-S, or they can

be combined to provide an OHI-S. Six selected teeth are scored: the buccal surfaces

of the maxillary first molars, the lingual surfaces of the mandibular first molars, and the labial aspects of the maxillary and mandibular left central incisors.


SIMPLIFIED ORAL HYGIENE INDEXOF GREENE AND VERMILLION (CONT.)

The plaque DI-S score ranges from 0 to 3 with the following scoring criteria: 0 = No debris or stain on the tooth surface 1 = Soft debris covering as much as one third of

the tooth surface or extrinsic stain without debris

2 = Soft debris covering one third to two thirds of the tooth surface

3 = Soft debris covering more than two thirds of the tooth surface


SIMPLIFIED ORAL HYGIENE INDEXOF GREENE AND VERMILLION (CONT.)

Adding the scores for all surfaces and then dividing that sum by the number of surfaces determines an individual score.

Adding the scores for each individual and then dividing that sum by the number of individuals determines a population score.


CALCULUS INDICES

Calculus has been measured in many epidemiologic studies, and the amount of calculus present is significant to the practice of the dental hygienist.


CALCULUS INDEX OF THE OHI-S

The CI-S and the DI-S use the same selected teeth and surfaces.

The scoring criteria also ranges from 0 to 3 with the following criteria: 0 = No calculus 1 = Supragingival calculus covering up to one third of

the tooth surface 2 = Supragingival calculus covering one third to two

thirds of the tooth surface or flecks of subgingival calculus

3 = Supragingival calculus covering more than two thirds of the surface or a continuous heavy band of subgingival calculus


CALCULUS INDEX OF THE OHI-S (CONT.)

OHI-S scores range from 0 to 6. To determine an individual OHI-S score:

Add the score of the DI-S and the score of the CI-S. To determine a group OHI-S score:

Add all the DI-S scores, and then divide that sum by the number of individuals to find the mean (average) DI-S.

Add all the CI-S scores, and then divide that sum by the number of individuals to find the mean (average) CI-S.

Add the mean DI-S score and the mean CI-S score, and then divide that sum by the total number of individuals to find the OHI-S.


VOLPE-MANHOLD PROBE METHODOF CALCULUS ASSESSMENT

The Volpe-Manhold Index scoring system measures only supragingival calculus.

To determine a score: Bisect each of the three parts of the lingual surface of

the incisor into the:Mesial lingualDistal lingualDirect lingual

With a periodontal probe, measure the height of calculus for each of the three lingual surfaces.


VOLPE-MANHOLD PROBE METHODOF CALCULUS ASSESSMENT (CONT.)

Adding together the three lingual surfaces and then dividing that sum by 3 determines a tooth score.

Tooth scores are averaged (added up and divided by the number of teeth measured) to provide a score for the individual.


INDICES OF GINGIVAL DISEASEOR BLEEDING

Indices of gingival disease are assessments of bleeding of the gingiva.

Bleeding is an important sign to monitor; it is associated with inflammation.

Bleeding on probing is the most common sign used in clinical practice to monitor gingival health.

Bleeding is associated with periodontal destruction.


GINGIVAL INDEX OF LÖE AND SILNESS

The gingival index (GI) is an evaluation of the four sides of the tooth—mesial, distal, lingual, and facial.

The index is scored by visual inspection of the gingiva and by gentle probing, stroking, or a sweeping motion into the sulcus.

A score is assigned to each surface, and an average score is assigned to each tooth.

Adding the tooth scores and averaging that number by the number of teeth examined determines the GI scores for areas of the mouth, for selected teeth, or for the full mouth.


GINGIVAL INDEX OF LÖE AND SILNESS (CONT.)

The following criteria are used for scoring: 0 = Absence of inflammation, no color change,

no texture change, and no bleeding on probing 1 = Mild inflammation, slight color change, little

change in texture, and no bleeding on probing 2 = Moderate inflammation, redness and swelling

of the gingiva, and bleeding on probing 3 = Severe inflammation, significant redness and

hypertrophy (swelling), tendency to bleed spontaneously, and ulceration


SULCUS BLEEDING INDEX

The sulcus bleeding index (SBI) is also a measure of bleeding on probing.

Similar to the GI, measurements are taken at the mesial, distal, buccal, and lingual surfaces.

A quadrant is probed, and the gingival units are scored 30 seconds after probing to allow time for bleeding to become visible.


SULCUS BLEEDING INDEX (CONT.)

The scoring units are based on the following criteria: 0 = Healthy appearance, no bleeding on probing 1 = Healthy appearance, no color or contour

change, bleeding on probing 2 = Bleeding on probing, color change in tissue,

no swelling


SULCUS BLEEDING INDEX (CONT.)

The scoring units are based on the following criteria: (cont.) 3 = Bleeding on probing, color change, slight

swelling of the gingival unit 4 = Bleeding on probing, obvious swelling with or

without color change 5 = Spontaneous bleeding, bleeding on probing,

color change, significant swelling with or without ulceration


INDICES OF PERIODONTAL DISEASE

Indices of periodontal destruction measure factors beyond gingival changes, including bone loss around the teeth.

Indices have been used to estimate periodontal health for individuals, communities, and populations.


RUSSELL’S PERIODONTAL INDEX

The Russell’s periodontal index (PI) is a scale that assigns a numeric score to each tooth.

This scale is weighted more toward bone loss than it is toward gingival inflammation.

The score for each tooth is added and averaged by all teeth examined in the individual, providing a score for each person.

Averaging the scores of individuals determines the population score.


RUSSELL’S PERIODONTAL INDEX (CONT.)

Criteria for scoring: 0 = Negative, no inflammation, no loss of function 1 = Mild gingivitis, inflammation in the free gingiva,

no inflammation circumscribing the tooth 2 = Gingivitis, inflammation circumscribing the

tooth, normal probing depths


RUSSELL’S PERIODONTAL INDEX (CONT.)

Criteria for scoring: (cont.) 6 = Gingivitis, pocket formation, deepened gingival

sulcus, normal function, no drifting 8 = Advanced destruction, loss of masticatory

function, tooth possibly loose, possible dull sound on percussion, possibly depressible in

the socket The higher scores of 6 and 8 indicate the

progressive nature of the scale.


PERIODONTAL DISEASE INDEXOF RAMFJORD

The Periodontal Disease Index of Ramfjord (PDI) evaluates the gingival condition and measures both probe depths and attachment loss.

The PDI is designed to evaluate six teeth that are representative of the entire dentition: #3–maxillary right first molar #9–maxillary left central incisor #12–maxillary left first bicuspid #19–mandibular left first molar #25–mandibular right central incisor #28–mandibular right first bicuspid


PERIODONTAL DISEASE INDEXOF RAMFJORD (CONT.)

Gingivitis Scoring is determined using the following criteria:

0 = Negative 1 = Mild gingivitis involving the free gingiva 2 = Moderate gingivitis involving the free and

attached gingiva 3 = Severe gingivitis with hypertrophy and

hemorrhage



Periodontal Disease When one tooth has probing depths that meet the

following criteria, the gingivitis score is disregarded and only the periodontal disease portion of the index is used for that tooth. 4 = Pocket depths on two or more of the surfaces of the tooth

measure up to 3 mm apical to the cementoenamel junction.

5 = Pocket depths on two or more of the surfaces of the tooth measure 3 to 6 mm apical to the cementoenamel

junction. 6 = Pocket depths on two or more of the surfaces of the tooth

measure more than 6 mm apical to the cementoenamel

junction. 37 Copyright © 2014, 2007, 2001, 1996 by Saunders, an imprint of Elsevier Inc.


The scores for each of the six teeth are added and then averaged to provide a score for the individual.

Individual scores can be averaged to compute a population score.


COMMUNITY INDEX OF PERIODONTAL TREATMENT NEEDS

The Community Index of Periodontal Treatment Needs (CIPTN) was developed by the World Health Organization.

The CIPTN assesses the periodontal treatment needs in a community, not simply the level of disease.

A specially designed periodontal probe is used. It is color-coded with a black band extending from 3.5 to

5.5 mm. It has a rounded ball tip and is 0.5 mm in diameter,

which helps prevent penetration of the probe tip into the connective tissue.


COMMUNITY INDEX OF PERIODONTAL TREATMENT NEEDS (CONT.)

Ten teeth are examined, two in each posterior sextant and one in each anterior sextant.

The teeth examined are #2, 3, 8, 14, 15, 18, 19, 25, 30, and 31.

Routines for scoring substitute teeth in the case of missing teeth are provided.

If a sextant has only one tooth, then it is considered and scored as part of the next sextant.



The worst finding for each tooth is coded, and the worst finding for the sextant is the treatment category for that sextant.

Individual tooth codes are as follows: 0 = No signs of inflammation or pocketing 1 = Gingival bleeding after probing 2 = Supragingival or subgingival calculus present 3 = Pathologic pockets of 4.0 to 5.5 mm 4 = Pathologic pockets of 6 mm or more



After the codes are assigned to teeth, the treatment categories are assigned per sextant on the basis of the highest score for each sextant.

The treatment categories are as follows: 0 = No treatment (code 0 only) I = Improvement in oral hygiene (code 1 only) II = Category I scaling (codes 2 and 3) III = Categories I and II complex periodontal

treatment (codes 2, 3, and 4)


GINGIVAL FLUID FLOW

Gingival fluid flow from the sulcus is an index primarily used in periodontal research studies to identify early inflammation.

An increase in the flow of crevicular fluid is one of the first measurable changes in the inflammatory process of the periodontium.

Fluid is measured on filter paper strips placed within the sulcus.

The measurement is made on a calibrated machine called a Periotron® (IDE Interstate, New York).


GINGIVAL FLUID FLOW (CONT.)

Comparisons of fluid flow can be made over time in a study population to estimate changes in the amount of inflammation present, or the information can be used in a cross-sectional comparison study of a larger population.

Gingival fluid flow has also been used as a measurement to define the level of inflammation present for patients to qualify to participate in clinical studies such as case-control studies.


PERIODONTAL SCREENINGAND RECORDING

The periodontal screening and recording (PSR) system enables the clinician to identify those patients who need a full examination and those patients who require only a screening examination in the private practice setting.

The World Health Organization CIPTN probe is used.

The periodontium is examined for inflammation, plaque, and calculus.

Sextants are graded individually, and only the worst score for the sextant is recorded.


PERIODONTAL SCREENINGAND RECORDING (CONT.)

The sextant evaluation is coded as follows: 0 = The colored section of the probe is completely

visible in the deepest probe depth; no calculus, defective margins, or bleeding are present.

1 = The colored section of the probe is completely visible in the deepest probe depth; no calculus or defective margins are present, but bleeding after probing is evident.

2 = The colored section of the probe is completely visible in the deepest probe depth of the sextant; supragingival or subgingival calculus or defective margins are present.



The sextant evaluation is coded as follows: (cont.) 3 = The color-coded section of the probe is only

partly visible in the deepest probe depth; calculus, defective restorations, and bleeding may or may not be present.

4 = The color-coded section of the probe completely disappears into the deepest probe depth.

= An asterisk is added to any of the codes if any notable features, such as furcation involvement, pathologic mobility, mucogingival defect, or marked recession, are identified.


*


Codes 0 and 1 require plaque control and preventive care.

Code 2 indicates plaque control, prevention, calculus removal, and the correction of defective restorations.

Codes 3 and 4 require a complete assessment, a full-mouth periodontal examination, and a periodontal treatment plan.

Regardless of the code, any sextant that has an abnormality asterisk (code ) requires a specific treatment plan.


*

MILLER INDEX OF TOOTH MOBILITY

The Miller index of tooth mobility (MI) scale is determined by placing two metal instrument handles on either side of the tooth to be tested, and moving the tooth in a facial-lingual direction.

The MI scale is graded as follows: 0 = No movement when force is applied. 1 = Tooth movement is barely distinguishable. 2 = 1-mm movement can occur in any direction. 3 = More than 1-mm movement can occur in any

direction, or the tooth is depressible or can be

rotated in the socket. The MI scale is often modified with plus or minus

signs or identified with Roman numerals.49 Copyright © 2014, 2007, 2001, 1996 by Saunders, an imprint of Elsevier Inc.

NATIONAL PREVALENCE DATA

The Third National Health and Nutrition Examination Study (NHANES-III) is a series of studies designed to characterize the health and nutrition status of the population of the United States.

It provides evidence about the oral health of the population.

The data described were collected and published between 1999 and 2004.


NATIONAL PREVALENCE DATA (CONT.)

Gingivitis Is defined in adults as bleeding on probing at one or

more sites Is more prevalent in:

Men than in women Mexican Americans than in non-Hispanic blacks or non-

Hispanic whites Low socioeconomic groups Those with less than a 12th-grade education



Periodontal Disease Is defined as one or more sites with 3 mm or more

of attachment loss and 4 mm or more of pocket depth Moderate disease

Two teeth with 4 mm of interproximal attachment loss or 5 mm or more of pocket depth at interproximal sites

Severe disease At least two teeth with 6 mm or more of

interproximal attachment loss and one tooth or more with 5 mm or more of pocket depth



Periodontal Disease (cont.) Percent with disease:

3.84% of adolescents and young adults, 10 to 34 years of age

10.41% of adults, 35 to 49 years of age 11.88% of senior adults, 50 to 64 years of age



Periodontal Disease (cont.) Gender

Men have more prevalence of disease than women, with 10.65% compared with 6.40%.

Socioeconomic status Individuals living below the federal poverty level were

found to have periodontal disease in 13.95% of the population, compared with 5.96% of the population for those living more than 200% above the federal poverty level.



Periodontal Disease (cont.) Education level

Individuals with less than a high school education had periodontal disease in 17.33% of the population, compared with 5.78% for those with more than a high school education.

Race and ethnicity Mexican-American individuals were affected by

periodontal disease in 13.75% of the population, compared with 16.81% for the non-Hispanic black population and 5.82% for the non-Hispanic white population.



Periodontal Disease (cont.) Smoking history

Periodontal disease in those who have never smoked was 5.94%.

Periodontal disease in former smokers and current smokers was 7.61% and 14.74%, respectively.



Periodontal Disease (cont.) Senior adults, 65 years of age and older

10.20% of those 65 to 74 years of age and 11.03% of those 75 years of age and older

More common in men than in women Twice as common in those living below the federal

poverty level More common in those with less than a high school

education Higher percentages in Mexican Americans and

non-Hispanic blacks than in non-Hispanic whites More common in current smokers than in those who

never smoked or who quit smoking


RISK FACTORS AND OTHER DETERMINANTS

Several determinants and risk factors are related to periodontal disease.

These risk factors are more prevalent in groups or populations with periodontal diseases than in those without.

These determinants and risk factors are associated with periodontal disease, but they do not cause disease.


RISK FACTORS AND OTHER DETERMINANTS (CONT.)

Gender Men are more likely than women to have periodontal

disease. Men tend to visit the dentist less often and

have poorer oral hygiene, which may explain the gender differences.

Age Disease worsens as a population ages.

Increased disease may better reflect a lifetime accumulation of disease effects, rather than more disease or more severe disease.



Socioeconomic status Lower income groups tend to have more periodontal

disease. This population also tends to have less dental

insurance coverage, be less educated, and visit the dentist less often than wealthier and better-educated people.

The differences noted in this population may exist because people with more education tend to have better-paying jobs, which may lead to better access to dental care.



Tobacco use Is associated with the extent and severity of periodontal

diseases Tobacco use, primarily smoking, has been associated

with increased levels of periodontal disease in adults and senior adults.



Events associated with smoking can be described as: Smokers have a higher prevalence of periodontal

pathogenic species in the plaque. Smoking suppresses the vascular reaction, resulting in

a masking of the signs of gingival inflammation. Smoking suppresses bleeding in periodontal disease. Granulocyte function may be reduced, contributing to

the decreased inflammatory signs.



Systemic disease Certain systemic conditions are also associated with an

increased risk of periodontal disease. Individuals with diabetes, particularly those with insulin-

dependent diabetes, are two to three times more likely to have more pocketing, more calculus, and more tooth loss than similar groups of individuals without diabetes.



Systemic disease (cont.) The presence of periodontal disease is considered to be

associated with cardiovascular disease. Low–birth-weight babies are more prevalent in women

with periodontal disease. Obesity has been suggested as a potential risk factor

for periodontal disease in the young population. Alcohol consumption has also been targeted by some

as a modifiable risk factor for periodontal disease in adults.


TRENDS IN DISEASE PREVALENCE

Trends in the epidemiologic data suggest that 10% or less of the population has periodontal disease and that the proportion increases with age and other variables.

The American Academy of Periodontology, in its position paper, suggests that the amount of periodontal disease in the American population is between 5% and 20%, with a significantly higher percentage having slight or moderate disease levels.


C HAPTER 3 Epidemiology of Periodontal Diseases Copyright © 2014, 2007, 2001, 1996 by Saunders, an imprint of Elsevier Inc.

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