Week 5 Flashcards
definition of epidemiology
study of the distribution and determinants of health related states or events in specified populations, and the application of this study to control health problems
define endemic
An endemic is a disease outbreak that is consistently present but limited to a particular region. This makes the disease spread and rates predictable (malaria)
define epidemic
unexpected increase in the number of disease cases in a specific geographical area
(yellow fever, measles, polio)
define pandemic
worldwide epidemic
define prevalence
proportion of persons in a population who have disease of interest at a given point or period of time
define incidence
average percentage of unaffected persons who will develop disease of interest during a given period of time
descriptive studies are based on:
observation
descriptive studies look at _______ and _________
involve case ____, case _____ and ______ studies
populations and individuals
reports, series, cross sectional
analytic studies involve _____ and _____ studies
_______ vs _______
cohort (group of people), intervention (clinical trials, ultimate goal is to stop the disease)
retrospective (today and back) vs prospective (today and forward)
define sensitivity
proportion of subjects with disease who test positive
define specificity
proportion of subjects without disease who test negative
how to calculate sensitivity and specificity
sensitivity: (positive with disease/total)
specificity (negative without disease/total)
define odds ratio
ratio of the odds that cases were exposed to the odds that controls were exposed
how to calculate odds ratio
odds ratio >1:
odds ratio < 1:
odds ratio = 1:
harmful
protective
no association
Papillary-MarginalAttachment (PMA) Index
Schour & Massler 1948
___ - absence of inflammation
____– presence of inflammation
Massler 1967
P – scale ___-___
M, A –scale __-___
0
1
0-5
0-3
Gingival Index
Loe & Silness 1963
0 =
1 =
2 =
3 =
normal
mild inflammation, no BOP
moderate inflammation, BOP
severe inflammation, spontaneous bleeding
Plaque Index
Silness & Loe 1964
0 =
1 =
2 =
3 =
0 = no plaque
1 = a film of plaque recognized only by probe
2 = moderate accumulation can be seen by eye
3 = abundance of soft matter
Periodontal Index
Russell 1956
0 =
1 =
2 =
(4) =
6 =
8 =
0 = negative
1 = mild gingivitis
2 = gingivitis, circumscribes the tooth
(4) = early resorption of alveolar crest on radiograph
6 = gingivitis with pocket formation
8 = advanced destruction of periodontium
Community Periodontal Index of Treatment Needs (CPITN)
WHO 1977
0 =
1 =
2 =
3 =
4 =
0 – health
1 – bleeding on probing
2 – calculus presence, PD < 3.5 mm
3 – PD 4-5 mm
4 – PD > 6 mm
define risk factors
Distinctive characteristics or exposures that increase the probability of developing periodontal disease
Risk Factors of Periodontal Disease
Bacterial plague
Age
Gender
Race
Smoking
Systemic diseases
Prevalence of Gingivitis
Highest prevalence occurs during ____-___ y/o group then gradually decreasing through ____-____ y/o group
____% aged 13 and older had at least one gingival bleeding site
13-17
35-44
54%
Prevalence of Periodontitis
Aggressive periodontitis
Adolescents ~ ____-____% (1986-87)
Greater in black or whites?
greater in black males or females?
greater in white females or white males?
0.13-0.53%
black
black males
white females
Prevalence of Chronic Periodontitis
Attachment loss increasing with ____
Maxillary ____ and mandibular _____ more likely have attachment loss
age
molars, incisors
