1. Dental caries
Presented by:
Dr. Shady A. M. Negm
Bachelor's Degree School of Dentistry,
Pharos University.
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2. Outline
• Definitions “caries “
• Distribution over time of dental caries
• Variation of caries within the mouth
• Susceptability of dental caries
• Determinant and Risk factor
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3. Definition of dental caries:
• An infective destructive process causing
decalcification of the tooth enamel and
leading to continued destruction of enamel
and dentin, and cavitation of the tooth
dental caries.
Or
• The formation of cavities in the teeth by
the action of bacteria; tooth decay.
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6. Variation of caries within the mouth
• The distribution pattern of dental caries
follows the accumulation of plaque
(Bacteria+Acids+Food debris)
• The most common sites are:
• Pits and fissures
• proximal areas
• cervical areas
• root caries oocurs in old age (>60) due to:
gingival recession ,plaque accumulation on the
root , xerostomia .
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9. Susceptibility of dental caries
THE LOWER MOLARS are THE MOST SUSCEPTIBLE
TO CARIES DUE TO:
• Its morphology( pits & fissures )favors for caries, is
overcomed by pit & fissure sealents.
• Forces of mastication.
• Effect of gravity
• The lower 6 is the first to erupt, so it stays for a longer
time..
The lower anterior teeth are the least susceptible to
caries due to:
• The effect of the tongue( washing &cleaning)
• Opening of the duct of submandibular gland (saliva)
• They are mostly covered by the upper anterior teeth
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11. Dental caries results from 3 groups of factors:
I. Host factors. (man)
II. Agent factors.
III. Environmental factors.
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12. I. Host factors:
1- Age:
It was found that the
greatest caries
incidence in
permanent teeth
occurs between 17
to 26 years of age.
Pit and fissure caries is
the predominant
type occurring at
this period.
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13. • A pronounced decrease in caries
incidence was shown at the period
between 26-35 years of age since the
more susceptible tooth surfaces have
already been affected by caries
• Another increase in caries incidence
occurs at about 45-55 years which is
the proximal type
• Over 60 years of age, root caries
occurs because root surfaces, become
denuded by gingival recession.
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14. 2- Sex:
Although the
female might be
expected to show a
higher caries rate
due to earlier tooth
eruption, a sex
difference was not
clearly
demonstrated.
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15. 3- Race:
• In USA, studies have
shown marked
difference in caries
experience between
white and black.
• Black have more
caries than white
people. The difference
in caries experience
indicates that white
people receive
different standards of
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care than black.
16. 4- Familial and genetic pattern of
caries:
It is difficult to distinguish
between true inheritance through
the chromosomes and the dietary
and other habits in the family.
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17. 5- Emotional disturbance:
Emotional disturbance, particularly
anxiety states, influence the incidence of
dental caries.
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18. 6- Variation of caries within the
mouth:
A) According to the tooth surfaces attacked:
a. pit and fissure caries,
b. Proximal caries,
c. Cervical caries,
d. Root caries.
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19. B) Frequency with which teeth are attacked:
Lower incisors are the least teeth
exposed to caries.
C) Bilateral symmetry
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21. 2- Role of carbohydrates:
Freely fermentable
carbohydrates have an
essential role in caries
process. Also the rate of
clearance from the
mouth affects the rate
by which bacteria may
act upon carbohydrates
to produce acids.
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22. Carbohydrates with rapid oral
clearance seem to be less risky in the
development of dental caries than those
which remain in the mouth for a longer time
thus sticky carbohydrates have higher risk
for caries.
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23. III. Environmental factors:
1. Geographic variation:
A) Temperature:
• Temperature acts to vary the caloric
requirements as well as the water
intake of human beings.
• Inhabitants of colder climates eat more
processed carbohydrates as
carbohydrates are quick cheap source
of warmth and energy.
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24. • This is associated with decrease in water
intake and therefore, caries incidence
increases. And the reverse occurs in areas
with high temperature.
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25. B) Sunshine:
As the sunshine increases, the amount
of ultraviolet rays increases which supply
vit. D. Also, there will be increased
demand for water consumption, which help
wash away food debris from the mouth.
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26. C) Rain fall:
As the rain fall increases leaching of
the minerals from soil especially
fluorides will lead to reduction of
fluoride concentration in crops. Rain
fall is accompanied by heavy clouds
which block sunlight.
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27. D) Humidity:
As humidity rises, the DMF rises too. This
is because of the decreased demand of
water intake in areas with high humidity
levels.
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28. 2- Fluoride:
Fluoride in the drinking water during the
time of tooth formation and mineralization
results in formation of fluoroapatite crystal,
which are more caries- resistant.
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29. 3- Total water hardness:
Measured in terms of calcium carbonate.
An inverse relation was reported between
DMF and the total water hardness.
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30. 4- Trace elements:
• Some are found in water but most are
found in greater concentration in food-
stuffs.
• It has been found that there is marked
increase in dental caries in areas where
selenium was high both in water and food-
stuffs.
• On the other hand, molybdenum and
vanadium have caries inhibiting
influences. 30
31. 5- Degree of urbanization:
• Urbanization may be accompanied by an
increase in dental caries.
• This may be due to the type of diet in urban
areas (refined and freely fermentable
carbohydrates).
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32. 6- Social factors:
Good economic status and social pressure
in the direction of good mouth appearance
are both strong factors in creating demand
for dental treatment, so the incidence of
caries is low.
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