Epidemiology and Intro to Periodontics

Question 1

What is the difference between jargon and lay language?

Answer 1

Jargon is language used between professionals. Lay language is communication with the patients.

Question 2

What is epidemiology?

Answer 2

Epi = upon
Demos = people
Ology = science

Epidemiology = the science of what falls upon people.

Question 3

Why are epidemiology studies used?

Answer 3

1. describe health status of the population.
2. To elucidate (explain) the etiology (cause) of diseases.
3. Identify risk factors.
4. Forecast disease occurrence.
5. Assist in disease prevention and control.

Question 4

What is prevalence?

Answer 4

Number of new cases at a given time over the number in the population at a given time.

Question 5

What does prevalence measure?

Answer 5

how much of some disease is in a population at a certain point in time. It is usually expressed as a fraction or percent. If low it is expressed as a number of cases per 100,000 people.

Question 6

What is incidence?

Answer 6

1. Number of new cases of disease in specified time (usually year) over the population that is disease free.

Question 7

What does incidence measure?

Answer 7

The rate of occurrence of new cases of a disease or condition in a specified period of time.

Usually incidence rates are small and expressed as a number of cases per 100,000

Question 8

What does extent mean?

Answer 8

how widespread the disease is in subjects (ex. the percent of teeth with decay in a subject)

Question 9

What does severity mean?

Answer 9

The mean CAL, mean bone loss etc…

Question 10

What are the main uses of epidemiology? (7)

Answer 10

1. to study the rise and fall of disease in a population
2. diagnose community problems
3. Estimate individual risk of developing a disease
4. Help in completing the clinical picture and natural history of disease by group analysis.
5. to identify clinical syndromes by observation of group behavior.
6. to evaluate the need and effectiveness of health services and need for man power.
7. To search for cause of disease and health

Question 11

What are the three ways of observational studies in epidemiology?

Answer 11

1. cross-sectional
2. cohort
3. case-control

Question 12

What is a cross-sectional study and why is it useful.

Answer 12

of people that have a disease at a particular time. It provides a lot of data and can help form hypotheses.

Question 13

What is a cohort study? What is its purpose?

Answer 13

1. Follow subjects over time. Its purpose is to determine whether exposure to a risk factor is associated with the development of disease.

Question 14

What is a requirement for a cohort study?

Answer 14

All subjects at the beginning of the trial need to be free of the disease that is being researched.

Question 15

What is a disadvantage of a cohort study?

Answer 15

They can require long periods of follow-up and can be expensive to conduct.

Question 16

What is a case-control study?

Answer 16

Subjects are recruited into the study based on their disease status. It investigates the association of exposure and disease. They ask the people a lot of questions and try to determine a pattern amongst all of them about why they got the disease.

Question 17

What is a disadvantage of a case-control study?

Answer 17

It can only lead to correlations

Question 18

What is a disadvantage of a case-control study?

Answer 18

It can only lead to correlations

Question 19

What is an index?

Answer 19

It is a numerical value given to everyone in the population in order to compare them. It has to have upper and lower limits. ex. plaque index

Question 20

What are the 9 characteristics of an ideal index?

Answer 20

1. Sensitivity - able to identify the condition being measured.
2. Clarity - criteria for scoring are logical and clearly spelled out.
3. simplicity - easy to use
4. objectivity - should be able to be applied without bias
5. acceptability - comfortable, non-threatening, or non-embarrassing to subject.
6. Validity - measures what it was intended to measure
7. Practicality - should be cheap and easy to use.
8. Reliability - constantly measure the same thing even in different conditions.
9. Quantifiability - measurements are meaningful of undergoing statistical analysis.

Question 21

What is the difference between accuracy and precision?

Answer 21

accuracy is the ability to hit a target. Precision is the ability to repeat that over and over.

Question 22

what is the scientific name for the color red?

Answer 22

erythematous

Question 23

What is microbial plaque?

Answer 23

Soft deposits that form a biofilm. It adheres to the tooth surface or other hard surfaces in the oral cavity.

Question 24

What does microbial plaque consist of?

Answer 24

1. microbial organisms

2. organic and inorganic compounds

Question 25

What is supra-gingival?

Answer 25

above the gum line

Question 26

what is sub-gingival?

Answer 26

Below the gum line

Question 27

what is sub-gingival?

Answer 27

Below the gum line

Question 28

What does exacerbated mean?

Answer 28

Makes it worse

Question 29

What are the two major types of periodontal disease?

Answer 29

gingivitis and periodontitis

Question 30

What is periodontal disease?

Answer 30

An infectious disease that involves inflammation.

It results in loss of tissue attachment and destruction of alveolar bone

Question 31

What are the stages of periodontal disease?

Answer 31

1. Periodontal health: state in which tissues are free from “clinical inflammation.”
2. Gingivitis: an inflammatory process confined to the gingival tissues and caused by nonspecific accumulation of plaque. Reversible usually.
3. Periodontitis: inflammation not just in the gingiva, also the attachment apparatus (cementum, periodontal lig., alveolar bone and soft tissues)

Question 32

Plaque index by Silness and Loe

Answer 32

0 = no visible plaque on visual inspection and sweep with periodontal probe.

1 = no visible plaque on visual inspection, but present upon sweep with probe.

2 = Mild to moderate visible plaque at the gingival 1/3 area

3 = Heavy plaque filling the gingival crevice. The interdental area is also filled with debris.

6 sites on each tooth is measured and counted.

Question 33

How is plaque index scored?

Answer 33

number of sites with plaque over (6x the number of teeth present) x 100 = % score (the lower the better)

Question 34

What is the Simplified Oral Hygiene Index?

Answer 34

(OHI-S)

There are two components, the debris component and the calculus component.

The degrees component (only used on 1st distal to 2nd bicuspid (B upper / L lower) and B of max. R and L of lower left central incisor):

0 = no visible debris or stain present

1 = debris or extrinsic stain covering up to 1/3 of the tooth surface.

2 = debris or extrinsic stain covering between 1/3 and 2/3 of tooth surface.

3 = debris covering more than 2/3 of surface.

The Calculus component:

0 = no calculus present.

1 = supra gingival calculus covering not more than 1/3 of surface.

2 = supra-gingival calculus covering 1/3 to 2/3 of surface or flecks of sub gingival calculus.

3 = supra gingival calculus covering more than 2/3 of surface or sub-gingival band of calculus.

Question 35

What is the gingival Index?

Answer 35

(PII) by Loe and Silness:

0 = normal gingiva with no signs of inflammation.

1 = mild inflammation: slight erythema and enlargement; no bleeding on gentle sulcus sweep.

2 = Moderate inflammation: moderate erythema, edema and glazing; bleeding on gentle sulcus sweep.

3 = severe inflammation: marked erythema and edema; ulceration; tendency to bleed spontaneously.

Question 36

How is the gingival index scored?

Answer 36

number of teeth with bleeding over (6 x the number of teeth present) x 100 = % score.

Question 37

How is hygiene index scored?

Answer 37

Its the opposite as the gingival index or plaque index. In those, the lower number the better, in the hygiene index, the lower number is worse.

Question 38

Periodontal Index (Russell)

Answer 38

0 = Negative: Healthy periodontium with no overt damage.

1 = Mild gingivitis: Overt inflammation in free gingival margin no encircling tooth.

2 = gingivitis: inflammation completely encircling tooth.

6 = gingivitis with pocket formation: Break in epithelial attachment with pocket formation. Normal masticatory function.

8 = Advanced destruction with loss of masticatory function: tooth may be loose; may have drifted; may sound dull on percussion with a metallic instrument; may be depressible in its socket.

Question 39

What are the teeth used for the Periodontal Disease index (Ramfjord 1959)

Answer 39

3, 9, 12, 19, 25, 28

ramfjord teeth: 16, 21, 24, 36, 31, 44

Question 40

What is the Ramfjord Periodontal Disease Index?

Answer 40

0 = no inflammation, no alterations in the gingiva

1 = Mild to moderate gingivitis at some locations on the gingival margin.

2 = Mild to moderate gingivitis of the entire gingival margin surrounding the tooth.

3 = Advanced gingivitis with severe erythema, hemorrhage, ulceration

4 = Up to 3 mm of attachment loss, measured from the cementoenamel junction.

5 = 3-6 mm of attachment loss.

6 = More than 6 mm of attachment loss.

Question 41

What is CPITN?

Answer 41

Community Periodontal Index of Treatment Need

Question 42

What are the classes of CPITN?

Answer 42

0 = Healthy periodontium, pockets less than 3 mm, no plaque, calculus or retention factors.

1 = gingival bleeding upon probing

2 = calculus or other retentive factors present

3 = pockets 4-5 mm

4 = pockets >6mm

/ = less than or equal to 1 tooth in sextant (whatever THAT means…)

Question 43

What is PTNS

Answer 43

Periodontal Treatment Needs System

Question 44

What are the classes of PTNS?

Answer 44

0 = periodontal health. no treatment needed

1 = needs improved personal hygiene - no calculus, pockets 6mm. Needs extensive scaling or surgery