Dental caries is a microbiological disease that results in localized demineralization of the inorganic portion and destruction of the organic substances of the tooth. It is caused by acid produced from bacteria in dental plaque when they metabolize carbohydrates. Key factors in the development of dental caries include diet, bacteria such as Streptococcus mutans, acids, dental plaque, and time. Common sites for dental caries include pits and fissures, proximal surfaces, and cervical margins. Treatment involves reducing sugar intake, fluoride application, and properly placed restorations to prevent recurrent caries.

1. Dental Caries
1

2. Definition
• Dental caries is defined as a microbiological
disease of the hard structure of teeth, which
results in localized demineralization of the
inorganic portion and destruct on of the organic
substances of the tooth.
• Cariology is a science which deals with the study
of etiology, histopathology, epidemiology,
diagnosis, prevent on and treatment of dental
caries.
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3. • Pits and fissures on occlusal surfaces of molars and premolar
• Buccal pits of molars
• Palatal pits of maxillary incisors
• Enamel of the cervical margin of the tooth just coronal to the gingival margin
• Proximal enamel smooth surfaces apical to the contact point
• In teeth with gingival recession occurring because of periodontal disease
• The margins of restorations predominantly which are defcient or overhanging
• Tooth surfaces adjacent to dentures and bridges.
SITES OF DENTAL CARIES
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4. 4

5. Etiology of Dental Caries
Diet
Caries
Bacteria
Time
Susceptible
Surface
(Host)
Possible interventions
Reduce intake of cariogenic
sugars Particularly sucrose
Possible interventions
Avoid frequent sucrose
intake (snacking)
Stimulate salivary flow
+ sugar clearance
Possible interventions
Reduce Strep. mutans
numbers by:
Reduction in sugar intake
Active or passive
immunization
Possible interventions
Water + other types of
Fluoridation
Prevention during post-
eruptive maturation
Fissure sealing
Properly contured
restorations5

6. Etiology of Dental Caries
Plaque
Acidogenic
Bacteria
Enzymes Food Acids Tooth Carious
Lesions
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7. THEORIES OF DENTAL CARIES
1. Acidogenic theory
2. Proteolytic theory
3. Proteolysis-chelation theory.
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8. Acidogenic Theory
 1890
 WD Miller
 dental decay is a chemoparasitic process consisting of 2 stages
1. decalcification of enamel results in total destruction
decalcification of dentin as a preliminary stage
2. followed by dissolution of softened residue of enamel and
dentine
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9. Factors that causes decay:
(1) Role of carbohydrates
(2) Role of microorganisms
(3) Role of acids
(4) Role of dental plaque
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10. RoleofCarbohydrates
Carbohydrates exert cariogenic effect which depends upon the following
factors:
1. Frequency of intake
2. Chemical composition, for example, monosaccharides and disaccharides
are more carious than polysaccharides
3. Physical form like solid, sticky jelly like or liquid
4. Time of contact of carbohydrate with the tooth
5. Presence of other food components like presence of high fat or proteins
makes carbohydrate less cariogenic.
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11. Roleofmicroorganisms
 caused by acid resulting from action of microorganisms on
carbohydrates
 S. mutans has been proved for the initiation of caries
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Initiation of Dental Caries Progression of Dental Caries
Streptococci
• S. mutans
• S. milleri
• S. mitior
• S. sanguis
• S. salivaris
Streptococcal species:
Streptoccal species in deep
dentinal caries and root
caries
Lactobacilli
• L. acidophillus
• L. casei
Lactobacilli in dentin
• L. acidophillus
• L. casei
Actinomycoses
• A. viscosus
• A. naeslundii
Actinomycoses
• A. Israeli
• A. odontolyticus

12. Roleofacids
 play most important role in pathogenesis of dental caries
 pH 5.5 is called critical pH
 Below this pH demineralization of tooth substance begins found
on uncleaned tooth surfaces
 appear as tenacious, thin film
 may accumulate within 24-48 hours
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13. Roleofdentalplaque
Dental plaque also known as microbial plaque is
important for beginning of caries because it
provides the environment for bacteria to form
acid, which causes demineralization of hard
tissue of teeth.
13

14. ProteolyticTheory
proteolysis of the organic components of tooth as
an initial process
 than actual demineralization + dissolution of
inorganic substances
proposed that enamel lamellae or rod sheath
(proteins) may be lysed
which means proteolysis as first event in further
progression of bacterial invasion +
demineralization carious lesions
14

15. ProteolysisChelationTheory
suggests that caries is caused by simultaneous events of
proteolysis + chelation
Proteolysis
destruction of organic portion of tooth by proteolytic
microorganisms
Chelation
removal of calcium by forming soluble chelates
 oral bacteria attack organic component of enamel (proteolysis)
 breakdown products have chelating ability and this dissolves tooth
minerals 15

16. 16

17. LOCAL FACTORSAFFECTING THE
INCIDENCEOF CARIES
• Tooth (Host)
– Variation in morphology
– Composition
– Position.
• Substrate (Environmental factors)
– Saliva
i. Composition
ii. Quantity
iii. pH
iv. Viscosity
v. Antibacterial factors.
17

18. • Diet
i Physical factors
ii. Local factors
a. Carbohydrate content: Presence of refined cariogenic
carbohydrate particles on the tooth surface
b. Vitamin content
c. Fluoride content.
d. Fat content
• Microorganisms: Most commonly seen
microorganisms associated with caries are
Streptococcus mutans and Lactobacillus.
• Time period.
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19. 19

20. 20

21. Classification
(1) Depending on nature of attack
(2) Depending on progression of caries
(3) Depending on surfaces involved
(4) Based on direction of attack
(5) Based on number of surfaces involved
(6) GV Black Classification based on treatment and
restoration design
(7) Based on location of lesion
(8) Based on tissue involved
21

22.  Primary Caries
 incipient; initial
 first attack on tooth surface
 Secondary Caries
 recurrent
 occurs on margins or walls
of existing restorations
Old Theories(1) Nature of Attack
22

23.  Acute
 rapidly invading process
 involves several teeth
 lesions are soft + light colored
Old Theories(2) Progression of Caries
23

24.  Acute
 usually pulp is involved at early stage
• Rampant caries
• Nursing bottle caries
• Radiation caries
 Chronic
 lesions are long standing
 fewer in number
lesions are long standing
 fewer in number
Old Theories(2) Progression of Caries
24

25.  Pit and fissure
 Smooth surface caries
Old Theories(3) Surfaces involved
25

26.  Forward Caries
 proceeds from enamel
to dentin
 lesion is triangle in shaped
with base of triangle at enamel
surface + apex towards
dentin
 in pits + fissures base is at DEJ
+ apex is in the pit
Old Theories(4) Direction of caries attack
26

27.  Backward Caries
 proceeds from DEJ towards
enamel surface
 also triangle shaped with
base at DEJ + apex towards
enamel surface
Old Theories(4) Direction of caries attack
27

28. 28

29.  Simple
 only one surface is involved
by caries
 Compound
 2 surfaces are involved
 Complex
 more than 3 surfaces involved
Old Theories(5) Number of Surfaces
involved
29

30.  Class I
 begin in pits, fissures +
defective grooves
 seen in occlusal surface
 occlusal two-thirds of molars
 lingual pits of incisors
Old Theories(6) GV Black Classification
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31.  Class II
 lesions seen on proximal
aspects of molars +
premolars
Old Theories(6) GV Black Classification
31

32.  Class III
 lesions involving proximal
aspects of incisors
 do not involve or necessitate
removal of incisal edge
Old Theories(6) GV Black Classification
32

33.  Class IV
 lesions involving proximal
aspects of incisors
 involve or require
removal of incisal edge
Old Theories(6) GV Black Classification
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34.  Class V
 lesions present on gingival
third of all teeth
Old Theories(6) GV Black Classification
34

35.  Class VI
 lesions found on incisal
edges + cusp tips
Old Theories(6) GV Black Classification
35

36.  Pit and Fissure caries
 Occlusal
 Buccal or lingual pit
 Smooth surface caries
 Proximal
 Buccal or Lingual surface
 Root caries
Old Theories(7) Location of the lesion
36

37. 37

38.  Enamel Caries
 Dentinal Caries
 Cemental Caries
Old Theories(8) Tissue involved
38

39.  Senile Caries
 caries associated with
aging
 almost exclusively seen on root
surface
 Residual Caries
 not removed during restorative
procedure
Classification
39

40.  Interproximal Caries
 opaque chalky region
(white spot)
 some cases yellow or brown
pigment area
 spots are generally located on
outer surface of enamel
between contact point + height
of free gingival margin
Clinical Features: Smooth Surface
Caries
40

41.  Interproximal Caries
 as caries penetrates
enamel, enamel surrounding
the lesion assumes bluish white
appearance
• usally apparent as laterally
spreading caries at DEJ
Clinical Features: Smooth Surface
Caries
41

42.  Interproximal Caries
 common for proximal
caries to extend both
bucally + lingually
Clinical Features: Smooth Surface
Caries
42

43.  Clinical Features:
 usually extends from
area opposite gingival crest
occlusally to convexity
of tooth surface
 extends laterally towards
proximal surfaces
Cervical, Buccal, Lingual or
Palatal Caries
43

44.  Clinical Features:
 usually occurs on cervical
area
 typical cervical lesion is a
crescent shaped cavity
beginning as slightly
roughened chalky area
 gradually becomes excavated
Cervical, Buccal, Lingual or
Palatal Caries
44

45.  Clinical Features:
 appears brown or black
 feel slightly soft
 catch a fine explorer point
Pit and Fissure Caries
45

46.  Clinical Features:
 enamel bordering the pit
and fissure may appear
• opaque as it becomes
• bluish white undermined
Pit and Fissure Caries
46

47.  Clinical Features:
 lateral spread of caries
at DEJ as well as
penetration into dentin
along dentinal tubules
may be extensive
 without fracturing away
overhanging enamel
 there may be large carious lesion
with only a tiny point of opening
Pit and Fissure Caries
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48. Pit and Fissure Caries
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49.  also known as cemental
caries
 involves both dentin +
cementum
 in number of people
exhibiting gingival recession
with clinical exposure of
cemental surface
Root Caries
49

50.  Clinical Features:
 slowly progressing
chronic lesion
 usually found in mandibular
molar area + premolar
region
 gingival recession is associated
with root surface caries
Root Caries
50

51.  occurs immediately adjacent
to restoration
 may be caused by inadequate
extension of restoration
 was not able to excavate or
removed well original
carious lesion
Recurrent Caries
51

52.  Clinical Features:
 restoration with poor
margins
• permitted leakage +
entrance of both bacteria +
substrate
Recurrent Caries
52

53.  Etiology:
 due to nursing bottle
containing milk or milk
formula, fruit juice or
sweetened water
 sometimes it occurs due to
sugar or honey-sweetened
pacifier
Nursing Bottle Caries
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54.  Pathogenesis:
 child is put on bed at
afternoon nap time or at night
with nursing bottle containing
milk or a sugar containing
beverage
 milk or sweetened liquid
becomes pooled around
maxillary anterior teeth
Nursing Bottle Caries
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55.  Pathogenesis:
 carbohydrate containing
liquid provide an excellent
culture medium for
acidogenic microorganisms
Nursing Bottle Caries
55

56.  Clinical Feature:
 prolonged feeding beyond
usual time may result in
early + rampant caries
 early carious involvement
of maxillary anterior,
maxillary + mandibular 1st
permanent molars,
mandibular canines
Nursing Bottle Caries
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57.  Clinical Feature:
 carious process is so
severe that only root
stumps remain
Nursing Bottle Caries
57

58.  Prevention:
 parent should start brushing
the child teeth as soon
as they erupt in oral
cavity
 discontinue bottle feeding as
soon as child can drink from
a cup, at approximately
12-15 months of age
Nursing Bottle Caries
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59.  suddenly appearing
 widespread
 resulting in early involvement
of pulp
Rampant Caries
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60.  Etiology:
 may be due to nutritional
deficiency
 malnutrition
 emotional disturbances
Rampant Caries
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61.  Clinical Features:
 occurs in children with
poor dietary habits
 extensive inter-proximal
+ smooth surface caries
Rampant Caries
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62.  Management:
 extensive dental care
 parent education
Rampant Caries
62

63.  Clinical Features:
 both deciduous + permanent
are affected
 large open cavities
 brown-stained polished
appearance + hard
Arrested Caries
63

64. ZonesinEnamelCaries
• Zone 1: Translucent zone
• – Represent the advancing front
of the lesion
• – Ten times more porous than
sound enamel
• – Not always present.
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65. • Zone 2: Dark zone
• – It lies adjacent and superficial to the
translucent zone
• – Usually present and thus referred as
positive zone
• – Called dark zone because it does not
transmit polarized light
• – Formed due to demineralization.
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66. • Zone 3: Body of the lesion
• – Largest portion of the
incipient caries
• – Found between the surface
and the dark zone
• – It is the area of greatest
demineralization making it
more porous.
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67. • Zone 4: Surface zone
• – This is zone is not or least affected by
caries
• – Greater resistance probably due to
greater degree of mineralization and
greater fluoride concentration
• – It is less than 5 percent porous
• – Its radiopacity is comparable to
adjacent enamel.
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68. ZonesofDentinalCaries
• Zone 1: Normal dentin
• – Zone of fatty degeneration
of Tome’s fibers
• – Formed by degeneration of
the odontoblastic process
• – Otherwise dentin is normal
and produces sharp pain on
stimulation.
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69. • Zone 2: Zone of dentinal sclerosis
• – Intertubular dentin is demineralized
• – Dentinal sclerosis, i.e. deposition of
calcium salts in dentinal tubules takes
place
• – Damage to the odontoblastic zone
process is apparent
• – There are no bacteria in this zone.
Hence, this zone is
capable of remineralization.
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70. • Zone 3: Zone of decalcif cation of dentin
• – Further demineralization of intertubular
dentin lead to softer dentin.
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71. • Zone 4: Zone of bacterial invasion
• – Widening and distortion of the
dentinal tubules which are f lled
with bacteria
• – Dentin is not self-repairable,
because of less mineral content and
irreversibly denatured collagen
• – This is zone should be removed
during tooth preparation.
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72. • Zone 5: Zone of decomposed
dentin due to acids and enzymes
• – Outermost zone
• – Consists of decomposed dentin
filled with bacteria
• – It must be removed during tooth
preparation.
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73.  Restorative Treatment
 Tooth Brushing
 Mouth Rinsing
 Dental Floss
 Topical Fluoride Application (Pedo Patients)
 Pit and Fissure Sealants
Prevention/Management of
Dental Caries
73

74. DIFFERENT WAYS FOR CARIES
PREVENTION
• Chemical Method
• Fluoride: Fluoride alters the tooth surface or/and tooth structure to
increase resistance to demineralization and prevent dental caries.
Fluorides are used in the following forms:
a. Fluoridation of water supplies
b. Topical application of fluoride
i. Sodium fluoride (NaF)
ii. Stannous fluoride (SnF2)
iii. Acidulated fluorido-phosphate
iv. Prophylactic paste
v. Fluoride dentifrices
vi. Fluoride mouthwashes or rinses.
• Chlorhexidine
• Zinc chloride
• Caries vaccine
• Vitamin K.
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75. Dietary Method
Caries can be prevented by the restriction of intake of
refined carbohydrate. Sucrose is most cariogenic
carbohydrate, hence its use in food should be
restricted.
Mechanical Methods
• Tooth brushing
• Dental floss
• Mouth rinsing
• Pit and fissure sealants
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