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Dr Aasim Masood
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DEFINITION:
“Absence of disease”.
WHO defined as
“a complete physical mental and social
well being and not merely an absence of
disease or infirmity”.
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The art and science of preventing and
controlling dental diseases in addition to
promoting the dental health through
organized community efforts
1.Dental health education to the public.
2.Preventing and controlling of dental diseases.
3.The applied dental researches.
4.Providing dental care programs that include
the prevention and treatment.
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To give better understanding of the patient
that should be treated as a part of the
community rather than a specific case that
needs treatment.
To realize the importance of implanting the
future dental practice based on the regular
maintenance of care and utilization of
preventive measures
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To provide the specialized skills and
knowledge that will enhance the future
practice dentistry.
To identify the community health problems
and suggest approaches for their correction
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assessing, reviewing, and recording a
patient’s risk for dental diseases, oral health
status and to “prescribing” an appropriate
treatment.
Clinical practitioner
1.Assessment of
dental, medical
history and oral
health status.
2.Diagnosis of the
patient oral health.
3.Treatment plan
based on diagnosis
and patient needs
and priorities.
Community dental practice
1.Survey of the commt oral health
status and their demographic
characters.
2.Analysis of the survey data to
determine health needs.
3.Program plan based on the
resources available and priorities
4.Payment method is
determined.
5.Evaluation during
treatment at specific
interval
4.Financing takes place.
5.Evaluation of the
program progress
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Dental public health deals with the whole
community rather than the individuals so, it
called community dentistry.
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Biomedical concept
Ecological concept
Psychosocial concept
Holistic concept
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Health has been viewed as “absence of
disease”.if person is free from any disease
than he is healthy. This found inadequate
because of major health problems
Malnutrition
Chronic disease
Accident
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Equilibrium between man and environment,
and disease a maladjustment of the human
organism to environment.
health is influenced by
1) social
2) psychological
3) cultural
4) economic
5) political
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Sound
Sound
Sound
Sound
mind,
body,
Family,
environment
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Opposite of health .
Any deviation from normal or state of complete
physical or mental well- being.
During 19th and early 20th century emphasis
shifted from emperical cause (bad air) to
microbes as the sole cause of the disease.
Disease Agent
Man
disease
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AGENT
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HOST
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ENVIROMENT
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Defined as
substance,living or
non-living,the
excessive presence or
relative lack of which
may initiate or
perpetuate a disease
process.
Classification:
1) Biological
2) Nutritional
3) Physical
4) Chemical
5) Mechanical
6) Social
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Defined as a person or
other animal,including
birds and or
arthropods,that affords
subsistence or
lodgments to an
infectious agent under
natural condition.
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Classification
Demographic i.e
age,sex.
biological Such as
genitic factors.
Social and economic
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Living conditions (housing, crowding,
water supply, refuse, sewage, etc)
Atmosphere / climate
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Pettenkofer (munich)
Due to advancement in public health, i.e
chemotherapy,antibiotics and vector control,
decline in communicable disease.
And beginning of new type disease
Lung Cancer,coronory heart disease,metal
illness.
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Model of disease suggested by Mac Mohan an
suited in d pugh,this model is ideally in
chronic disease. Where the agent is not
known, but is the outcome of interaction of
multiple factors.
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Prepathogensis phase
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Pathogensis phase
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When the disease agent is not firmly
established the etiology is generally
discussed in terms of risk factor.
The risk factor does not mean that the
disease will occur ,and its absence it will
occur.
e.g smoking and occupational exposure(dye
and leather) in bladder cancer.
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On the other hand smoking has an affect on
the hypertension and high blood cholesterol.
The risk factor may be causative or mrely
contributory factor.
So some risk factor can be modified like
smoking ,alchol,but some (age,sex) cannot be
modified .
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symptomatic disease
What the physcian
sees
----------------------------------------Presymptomatic
what the
disease
Physcian does m--------------------------not see
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Figure 6.6 The pyramid and iceberg of disease
1
Diseased, diagnosed &
controlled
2
Diagnosed
disease
Diagnosed, uncontrolled
3
Undiagnosed or wrongly
diagnosed disease
4
Risk factors for disease
5
Free of risk factors
Undiagnosed or
wrongly diagnosed
disease
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Prostate cancer based on cases diagnosed in hospital
would lead to the view that the disease is usually, if not
always, progressive.
Unselected cases show that prostatic cancer can in some
cases be a static, or slowly progressive, phenomenon.
Patients who are at the tip of the iceberg are more likely to
have multiple health problems than others.
People with cardio-respiratory problems and diabetes are
more likely to be admitted to hospital, than people with
only one of these two problems. This is the basis of the
bias known as Berkson's bias.
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Screening is the testing of apparently healthy
populations to identify previously undiagnosed diseases
or people at high risk of developing a disease.
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Screening aims to detect early disease before it
becomes symptomatic.
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The choice of disease for
which to screen;
The nature of the screening
test or tests to be used;
The availability of a
treatment for those found to
have the disease;
The relative costs of the
screening.
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There should be a suitable test or examination.
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The test should be acceptable to the
population.
1.Acceptability
2.Repeatability
3.Validity:validity has two components
i. Sensitivity
ii. specificity
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Ability of the test to identify correctly all
those who have the disease,and is called true
positive.90 percent of sensitivity means 90 %
of the disease people screened by the test
will give a “true positive” result and the
remaining 10% false negative.
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Ability of the test to identify correctly those
who don’t have the disease, that is true
negative.90% specificity means 90 percent of
the non diseased person will give true
negative result.
Outcomes of a Screening Test
True Disease Status
Screening
Test
Positive
Negative
Total
Positive
True Positives
a(TP)
False Positives
b(FP)
TP+FP
Negative
False Negatives
c(FN)
True Negatives
d(TN)
FN+TN
FP+TN
TP+FP+FN+TN
Total
TP+FN
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a denotes true positive individuals with
having disease.
b denotes false positive test results and
don’t have the disease.
c denotes false negative test results but who
have the disease.
d denotes true negative who do not have the
disease and test result is negati.ve
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Sensitivity =a/(a+c)100
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Sepcificity =d/(b+d)100
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DEFINATION
Entry and development or
multiplication of infectious agent in the body
of man or animal .
Sources of infection is defined as the person,
animal ,object or substance from which an
infectious agent passes or is disseminated to
host.
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Reservoirs is defined as any person, animal
arthropods or combination of these in which
an infectious agent lives and multiplies, on
which it reproduces itself in such a manner
that it can be transmitted to a susceptible
host.
Types of Reservoirs
1) Human
2) Animal
3) Reservoir in non living.
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Definition of epidemiology
The study of the health and the disease in
human population and how these statuses
are influenced by the environment and way of
living.
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Study the pattern of the diseases among
population. o
Collection of data to understand the natural
history to the disease which lead to formulation
of hypothesis to explain the disease.
Planning and evaluation of dental health services.
To identify the etiological factors responsible for
a disease.
To identify special groups more susceptible to
oral diseases and allow planning for preventive
services.
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1.Formulation of the hypothesis.It aim to put
the idea of the investigator in the form of a
null hypothesis, which is the starting point of
any investigation.
2.Designing the investigation, using the
methods of epidemiological studies
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3.Selection of the sample.
4.Conducting the investigation, with the main
three aspects when conduct the examinations
The examination method. The diagnostic
criteria. The indices used for measurements.
.Analysis of data.
Drawing the conclusion.
Publishing the results.
Many diseases are preventable through
simple, non-medical methods as most
common oral diseases (dental caries and
periodontal diseases). Prevention of oral
diseases depends upon data collected from
the epidemiology of the diseases which can
identify the etiological factors concern with
the diseases and find the methods to control
or prevent it.
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Prevention can divided into the following
levels of preventive services.
1-Primary preventive services
It is instruction and education of expectant
mother (pregnant) to keep good oral hygiene
of the child and include prevention.
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It is to prevent the initiation of the disease;
they are designated as service that
provides.Health promotion and specific
protection.
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Specific protection activity includes services
that are designated to protect against disease
agent by decreasing the susceptibility of host
or by establishing barrier against
environment
It is the prevention and reversing the
progress of initial stages of disease or to
arrest the disease progress before treatment
become necessary e.g. Remineralization of
carious lesion, fluoride, and dental sealant.
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Secondary preventive services:
It is the employs routine treatment method
to terminate a disease process and to restore
tissue to as near as possible e.g.
Restorative treatment,
Endodontic treatment,
Periodontal treatment.
It is included the early diagnosis and the
prognosis of treatment.
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Tertiary Preventive Services:
These services directed
toward the end result of disease, also can be
referred as replacement therapy, these
activities provide measures necessary to
replace lost tissue and to rehabilitate patient
to the point that function is near normal as
possible e.g. prosthetic appliance and
implant.