08. exogeneous prevention

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Transcript 08. exogeneous prevention

EXOGENEOUS PREVENTION
INTRODUCTION
Dental caries is defined as a progressive irreversible
microbial disease affecting the hard parts of tooth
exposed to the oral environment, resulting in
demineralization of the inorganic constituents and
dissolution of the organic constituent, thereby leading to
a cavity formation.
• The word caries derived from Latin meaning ‘rot’ or
decay
• Similar to the Greek word ‘ker’ meaning death
• The relationship between diet and dental caries
Bacterial enzymes + fermentable carbohydrates = acid,
Acid + enamel = dental caries
CURRENT TRENDS IN CARIES
INCIDENCE
• In developed countries, caries prevalence
declined in last decade, causes are
multifactorial. Eg: communal water
fluoridation.
• In developing countries increase in caries
prevalence, cause is increased use of
refined carbohydrates.
CARIES SUSCEPTIBILITY JAW
QUADRANTS
• Bilateral distribution between the right and
left quadrant of both maxillary and
mandibular arches.
• Maxillary teeth more susceptible than
mandibular arch
 relate to gravity and saliva, with its
buffering action, would tends to drain from
upper teeth and collect around lower teeth.
CARIES SUSCEPTIBILITY OF
INDIVIDUAL TEETH
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Upper and lower first molar
 95%
Upper and lower second molar
 75%
Upper second bicuspid
 45%
Upper first bicuspid
 35%
Lower second bicuspid
 35%
Upper central and lateral incisor
 30%
Upper cuspids and lower first bicuspid
 10%
Lower central and lateral incisor
 3%
Lower cuspids
 3%
Teeth farthest back in the mouth are more frequently carious.
Caries susceptibility of individual tooth surface
occlusal > mesial > buccal > lingual
ECONOMIC IMPLICATION OF
DENTAL CARIES
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Factors changing the economic implication of
treatment of dental caries :Economic status of population
Increasing educational status
Growing number of dental graduates
Insurance programs
Commercial pressure
Governmental influences
CLASSIFICATION OF DENTAL
CARIES
A) Black’s classification
CLASS I – cavities on the occlusal surface of premolars
and molars, on the occlusal two-third of the facial and
lingual surface of molars, on lingual surface of maxillary
incisors.
CLASS II – cavities on the proximal surface of posterior
teeth
CLASS III - cavities on the proximal surface of anterior
teeth that do not include the incisal angle
CLASS IV – cavities on the proximal surface of anterior
teeth that include the incisal angle
CLASS V – cavities on the gingival third of the facial or
lingual surface of all teeth
CLASS VI - cavities on the incisal edge of anterior teeth or
occlusal cusp height of posterior teeth
B[1] According to location on individual
teeth
- Pit and fissure caries
- Smooth surface caries
B[2] According to the rapidity of the process
- Acute dental caries
- Chronic dental caries
B[3]
- Primary caries (virgin)
- Secondary caries (recurrent)
PIT AND FISSURE CARIES
- Pits and fissures with high steep walls &
narrow base  retention of food, debris,
micro organisms  fermentation  acid
production
- Caries appear brown/ black, feel soft
- Enamel bordering  opaque bluish
white
- Large carious lesion with a tiny point of
opening
SMOOTH SURFACE CARIES
- Preceded by formation of microbial/ dental
plaque
- Begins just below contact point and appear in
early stages as faint white opacity of enamel
(chalky spot)  slightly roughened 
surrounding enamel bluish white as caries
penetrate enamel
- Cervical carious lesion crescent shaped
cavity (extend from areas opposite to the
gingival crest occlusally to convexity of tooth
surface)
ACUTE DENTAL CARIES
- Rapid clinical course & early pulp
involvement
- Process rapid  little time for deposition of
sec. dentin. Dentin stained a light yellow
- Rampant caries, affecting deciduous dentition
 nursing bottle caries
- Commonly 4 maxillary incisors followed by
first molar and then cuspids
- Absence of caries in mandibular incisors
distinguished from ordinary rampant caries
• CHRONIC DENTAL CARIES
- Progress slowly and leads to involve pulp
much later
- Sufficient time for both sclerosis deposition of
sec. dentin
- Carious dentin stained deep brown.
- cavity shallow with min. softening of dentin
- Pain and undermining of enamel not a
common feature
RECURRENT CARIES
- Occurs in immediate vicinity of restoration
- Poor adaptation of filling material
ARRESTED CARIES
- Static or stationary caries
- Exclusively in caries of occlusal surface
- Large open cavity and lack of food
retention
- Superficially retained and decalcified
dentin gradually burnished until it takes
a brown stain, polished appearance and
is hard  EBURNATION OF DENTIN
- Caries on proximal surface of teeth 
adjacent approx. tooth extracted
THEORIES OF CARIES
FORMATION
• Legend of the worm theory
• Endogenous theories
 Humoral theory
 Vital theory
• Exogenous theory
 Chemical (acid) theory
 Parasitic (septic) theory
 Miller’s chemicoparasitic theory – Acidogenic theory
 Proteolysis theory
 Proteolysis chelation theory
 Sucrose – chelation theory
• Other theories
 Auto immune theory
 Sulfatase theory
ETIOLOGIC FACTORS IN DENTAL
CARIES
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Dental caries is a multifactorial
disease in which there is an interplay
of 3 principle factors.
I. The host ( teeth, saliva etc.)
II. Micro flora
III. Substrate (diet)
In addition the fourth factor, time
must be considered.
I. HOST FACTORS
Tooth
• Composition
• Morphologic characteristics
• Position
Composition of tooth
Enamel:- Inorganic : 96%
- Organic + water : 4%
Dentin:- Organic matter +water :35%
- Inorganic :65%
Cementum:- Inorganic : 45-50%
- Organic +water : 50- 55%
Morphological characteristics of the tooth
• Feature predisposed to the development of
dental caries is presence of deep narrow
occlusal fissure/ buccal and lingual pits
Tooth position
• Which are malaligned, out of position, rotated
or otherwise not normally situated, may be
difficult to clean and tend to favor the
accumulation of food and debris which
subsequently lead to dental caries
Saliva
• Composition
• PH
• Quantity
• Viscosity
• Antibacterial factors
Composition of saliva
Inorganic:Positive ions:- Ca, Mg, K,
Negative ions:- CO2, Cl, F, PO4,
thiocynate
Organic:Carbohydrates : glucose
Lipids : cholesterol, lecithin
Nitrogen : non- protein ammonia,
nitrites & amino acids
protein  globulin, mucin, total
protein
Miscellaneous : peroxides
Enzymes : carbohydrases, proteases,
oxidases
PH of saliva
• Determined by bicarbonate concentration
• PH increases with flow rate, normal PH 7.8
• Sialin is an argenine peptide described PH
rise factor, present in saliva
Quantity of saliva
• Normal quantity 700-800 ml per day
• In case of salivary gland aplasia and
xerostomia in which salivary flow may entirely
lacking, resulting in rampant dental caries
Viscosity of saliva
• Thick, mucinous saliva increases the dental
caries
Antibacterial properties of saliva
Lactoperoxidase
• They participate in killing of microorganisms
by catalyzing the H2O2 mediated oxidation of
a variety of substances in the microbes
• Utilizing thiocynate ions in saliva peroxidation
generate highly reactive chemical compound
that bond and inactivate general intracellular
microbial enzyme system, as well as
microbial surface compound.
Lysozyme
• Small, highly positive enzyme that catalyze
the degradation of negatively charged
peptidoglycan matrix of microbial cell wall
Lactoferin
• Fe binding basic protein found in saliva with mol. wt.
near 80,000.
• Tends to bind & link the amount of the free Fe which
is essential for microbial growth
IgA
• Immunoglobulin in saliva
• Inhibit adherence and prevent colonization of
microbial on tooth and mucosal surfaces
Other salivary components with protective function
Proline rich protein
• Mucus and glycoprotein
• Because of their high proline content, there are rigid
collagen like molecules designed to form a pseudo
membranous layer in the hard and soft oral surfaces
as well as on the oral flora.
Aromatic rich protein
• Statherin
• It causes remineralization
Other host factors
Age
• Dental caries decreases as age
increases
• Root caries are common in elders
• Gingival recession  cemental
exposure (improper brushing)
Socioeconomic status
• High  low chance
• Low  more chance
II. MICROFLORA
• Strep. mutans  early carious lesions of enamel
• Lactobacilli  dentinal caries
• Actinomyces  root caries
Role of microorganisms in dental caries
• Prerequisite for dental caries initiation
• A single type of microbe is capable of
inducing dental caries
• Ability to produce acid  prerequisite
for caries induction
• Streptococcus strains are capable of
inducing caries
• Organisms vary greatly in their ability to
induce caries
Role of dental plaque
• soft, non mineralized, bacterial
deposit which forms on a teeth that
are not adequately cleaned
• Complex metabolically interconned
highly organized bacteria/
ecosystem
• Important component of dental
plaque is acquired pellicle  just
prior or concomitantly with bacterial
colonization and may facilitate
plaque formation
• Microbial in dental plaque
 streptococci
 actinomycetes
 veillonella
• Strep. mutans  chief etiological
agent of dental caries
III. DIET
• Increase in carbohydrate increase carious activity
• Risk of caries is greater if the sugar is consumed in a
form that will be retained on the surface of the teeth
• Risk of sugar increasing caries activity if it is consumed
between meals
• Increasing caries activity varies widely between
individuals
• Upon withdrawal of the sugar rich foods the increased
caries activity rapidly disappears
• Carious lesion may continue to appear desperate to
avoidance of refined sugar and maximum restriction on
natural sugars dietary carbohydrates
• High concentration sugar in solution and its prolonged
retention on the tooth surface leads to increased caries
activity
• Clearance time of the sugar correlates closely with
caries activity
THE CARIES PROCESS
• Caries of enamel
 smooth surface caries
 pit and fissure caries
• Caries of dentin
• Caries of cementum
SMOOTH SURFACE CARIES
• Earliest manifestation is the appearance of an
area of decalcification, beneath dental plaque
with a smooth chalky white area
• Loss of interprismatic substance with increase in
prominence and roughening of ends of enamel
rods
• Accentuation of incremental striae of retzius
• As this process advances and involves deeper
layer of enamel it forms a cone shaped lesion
with apex towards DEJ and base towards
surface of teeth
PIT AND FISSURE CARIES
• Because pit and fissure provides more depth 
increased food stagnation with bacterial decomposition
• Here caries follow direction of enamel rods and forms a
cone shaped lesion with apex at outer surface and base
towards DEJ
Different zones present in lesion are
Zone 1: translucent zone 
Advancing front of enamel lesion, not always present
Zone 2: dark zone 
Referred as positive zone formed as a result of
demineralization
Zone 3: body of lesion 
Area of greatest mineralization
Zone 4: surface zone 
Appears relatively unaffected
CARIES OF DENTIN
• Initial penetration of dentin by caries may result in
dentinal sclerosis
• This is a reaction of vital dentinal tubules and a vital
pulp, in which results in calcification of dentinal tubules,
that tend to seal them off against further penetration by
microorganisms
• The different zones which are present in carious dentin
are (beginning pulpally at advancing edge of lesion)
Zone 1 : zone of fatty degeneration of Tome’s fibres
Zone 2 : zone of degeneration
Zone 3 : zone of decalcification
Zone 4 : zone of bacterial invasion of decalcified but intact
dentin
Zone 5 : zone of decomposed dentin
ROOT CARIES
• Defined as soft progressive lesion that is
found anywhere on root surface that has
lost connective tissue attachment and
exposed to oral environment
• Microorganisms involved in root caries are
filamentous
• Microorganisms invade cementum, along
sharpey’s fibres
INDICES USED TO ASSESSMENT
OF DENTAL CARIES
1.
2.
3.
4.
5.
DMFT index
DMFS index
DEF index
Stone’s index
Caries severity index
Diagnosis of caries
1. Identification of subsurface demineralization
(inspection/ palpation, radiographs)
2. Bacterial testing (caries activity testing)
3. Assessment of environment conditions like salivary
PH, flow and buffering
METHODS OF CARIES CONTROL
•
There are various levels for prevention of
dental caries
these include
1. Primary prevention
2. Secondary prevention
3. Tertiary prevention
levels of
prevention
Primary prevention
Secondary
prevention
Tertiary prevention
Preventive
services
Health promotion
Specific
protection
Early diagnosis
and prompt
treatment
Disability
limitation
Services
provided
by the
individual
Diet planning,
demand for
preventive
services, periodic
visit to dental
office
Appropriate use
of fluoride,
ingestion of
fluoridated water,
use of fluoridated
dentifrices
Self examination
and referral,
utilization of
dental services
Utilization of
dental
services
Services
provided
by
community
Dental health
education
programs,
promotion of lobby
efforts
Comm. or school
water
fluoridation,
school fluoride
mouth rinse
program, school
fluoride tablet
program, school
sealant program
Periodic
screening and
referral, provision
of dental
services
provision of
dental
services
provision of
dental services
Services
provided
by the
dental
profession
Patient education,
plaque control
program, diet
counseling, recall,
reinforcement,
caries activity tests
Topical
application of
fluoride,
supplements/
rinse preparation,
pit and fissure
sealants
Complete exam,
prompt treatment
of incipient
lesions,
preventive resin
restoration, pulp
capping
Complex
restorative
dentistry
Removable and
fixed
prosthodontic
minor tooth
movement,
implants
Rehabilitation
Utilization of
dental services
METHODS TO CONTROL CARIES
1. Chemical measures
2. Nutritional measures
3. Mechanical measures
1. CHEMICAL MEASURES
A vast number of chemical substances have been
proposed for the purpose of controlling dental caries
Ideal properties:
• It should be safe for intraoral use
• Must be able to penetrate dense microbial plaque
• Agent used for topical application should not be
systematically toxic if swallowed accidentally
• Should not produce local tissue irritation
• Should be rapidly bactericidal as contact time is less
• Should possess degree of specificity
• Should be destroyed or inactivated by GIT
• Should have an acceptable taste
• Medically important antibiotics should not be used
Chemical measures include:
I.
Substances which alter tooth surface or
tooth structure
II. Substances which interfere with
carbohydrate degradation through
enzymatic alteration
III. Substances which interfere with bacterial
growth and metabolism
I. SUBSTANCES WHICH ALTER
TOOTH SURFACE/ TOOTH
STRUCTURE
•
Chemicals falling into this categories
include
a.
b.
c.
d.
e.
Fluorides
Iodides
Bisbiguanides
Silver nitrates
Zinc chloride and potassium ferrocyanates
Fluoride
• Most widely used and promising chemical in
this category
• Fluorides have been administrated
principally in two ways
a. Systemic application
eg:- School water fluoridation, community water
fluoridation, milk fluoridation, self fluoridation
b. Topical application
eg:- Sodium fluoride, aciduated phosphate
fluoride, stannous fluoride
•
A fluoride concentration of 1 ppm in drinking
water is associated with a marked decrease
in dental caries
• Other methods of using fluorides are
 As dietary supplementation of fluoride
 Fluoride dentifrices
 Fluoride in mouth washes/ rinses
 Fluoride incorporated in chewing gums and dental
floss
• Rinses for caries reduction
Rinse
Concentratio
n
PH
Application
Aqueous
NaF
0.2%
7
Once a wk/
once
every 2
wk
Aqueous
NaF
0.5%
7
Once daily
Aqueous
APF
0.02%`
4
Once daily
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The effect of fluoride influencing its
anticaries actions are:Interference in enzymatic process of
bacteria
Direct bactericidal action
Reduction of plaque formation
Enhancement of enamel
remineralization
Stimulation of formation of large
appetite crystal
Lowers the solubility of enamel
Iodine
•
Used as a antibactericidal mouth
rinses
•
Kills microorganisms immediately
•
Disadvantages : metallic taste, stain
metallic or composite restorations
Bisbiguanides
•
The two most common commercially
available bisbiguanides are:
a) Chlorohexidine
b) Alexidine
•
These are potential anticaries agents
•
They are bactericidal
•
Have both hydrophobic and
hydrophilic constituents and possess a
net +ve charge – adsorbs –vely
charged membrane surface and
damage to the membrane by breaking
permeability barrier
•
Disadvantages
1.
2.
3.
4.
5.
Stains teeth and dorsum of tongue
Evidence of bacterial resistance
Bitter taste
Mucosal irritation and desquamation
Allergic reaction
Silver nitrate, zinc chloride and
potassium ferrocyante
- seal off the enamel caries invasion
pathway by getting impregnated to the
enamel
II. SUBSTANCES WHICH INTERFERE
WITH CARBOHYDRATE DEGRADATION
THROUGH ENZYMATIC ALTERATIONS
•


-
Includes:1. Vitamin K
2. Sarcoside
Vitamin K
Vit. K was found to prevent acid formation in
incubated mixtures of glucose and saliva
Sarcoside
Sodium-N-lauryl sarcosinate & sodium
dehydroacetate were promising enzyme
inhibitors or antienzymes. They have the ability
to reduce the solubility of powdered enamel
III. SUBSTANCES WHICH INTERFERE
WITH BACTERIAL GROWTH AND
METABOLISM
Includes:• Urea and ammonium compounds
• Chlorophyll
• Nitrofurans
• Antibiotics
• Caries vaccines
Urea and ammonium compounds
• Potential anticariogenic agents.
• Urea  degradation by urease  ammonium
 neutralize acids
• They are cationic antiseptic and surface
active agents
• More active against GPB.
• Mechanism of action:- +vely charged
molecules reacts with –vely charged cell
membrane phophates and thereby disrupts
the cell wall structure microorganisms.
Eg:- benzathonium chloride, benzalleonium
chloride, cetylpyredinium chloride
Chlorophyll
• Water soluble form of chlorophyll is capable
of preventing or reducing the PH fall in
carbohydrate
• Saliva mixture invitro chlorophyll is
bactriostatic
Nitrofurans
• These compounds have been found to exert
bactriostatic and bactriocidal action
• Act on both aerobic and anaerobic
microorganisms
• Eg:- furacin 0.2% cream
Antibiotics
• Penicillin:- as an anticariogenic compound, act on cell
wall synthesis
disadvantage: resistance
• Erythromycin:- act on bacterial protein synthesis
Disadvantage: diarrhoea and resistance
• Kanamycin:- act on bacterial protein synthesis. It
reduced S. Mutans and S. Sanguis population in
plaque
Disadvantage: nephrotoxicity and ototoxicity
• Others:- spiramycin, tetrcycline, tyrothricin,
vancomycin
Caries vaccine
• Caries vaccine dates back to a period, when
lactobacilli were thought to be of paramount of
importance. Oral administration of S. Mutan vaccine
leads to accelerated clearance S. mutans from
mouth.
NUTRITIONAL MEASURES
The chief nutritional
measures advocated for
the control of dental
caries is restriction of
refined carbohydrate
intake.
Other measures include
- Avoiding sugar that
retains of teeth surface
- Avoiding sugar in
between meals
- Eating of phosphated
diets
Phosphated diet
Phosphates are anticariogenic sodiummeta phosphate appear to
be most effective. Phosphate exhibit their cariogenic action
via local factors like:1.
Reduction of enamel solubility
2.
Buffering effect in neutralizing salivary plaque
3.
Rendering fats, carbohydrates and proteins which are less
cariogenic
4.
Interference with enzymatic process on enamel surface to
increase host resistance
5.
Decrease in bacterial adhesion
6.
Interference with enzymatic process on enamel surface to
increase host resistance
7.
Interference with synthesis of extra cellular polysaccharide
formation
8.
Maintenance or increase of plaque calcium and phosphorous
level.
•
Other inhibitors like pyridoxine, fat, tannic acid, xanthines,
constituents of cocoa butter are believed to have caries
protective factors. Nutritional or dietary means of caries
control is impossible to achieve on basis of mass prevention
program
MECHANICAL MEASURES
•
1.
2.
3.
4.
5.
6.
This refers to procedures specifically
designed for and aimed at removal of
plaque from tooth surface methods for
cleaning tooth mechanically are:
Prophylaxis by dentist
Tooth brushing
Mouth rinsing
Use of dental floss or tooth picks
Incorporation of detergents foods in
diet
Pit and fissure sealants
Dental prophylaxis
• Careful polishing of
roughened smooth surface
and correction of faulty
restoration decreases the
formation of bacterial plaque
and there by reducing the
development of new carious
lesion
Tooth brushing
Types of tooth brushing
- Manual
- Powered
- Sonic and ultrasonic
- Ionic
ADA specification for a tooth
brush
- 1- 1.25 inches length
- 5/16 – 3/8 inches in width
- 2 – 4 rows of bristles
- 5-12 tufts per row
Mouth rinsing
• Use of mouth wash for the benefit of its action in
loosening food debris from teeth has been suggested to
be of value as caries control measures.
Dental floss
• Dental flossing is effective in removing plaque and
dislodge the irritating matter that is real source of
disease.
• Used in type I gingival embrasures
It is available in:
- Multifilament – twisted / non twisted
- Bounded / unbounded
- Thick / thin
- Waxed / non waxed
Oral irrigators
- Use of flushing devices
- Irrigation devices composed of a built in pump and a
reservoir
- It can also be used to deliver antimicrobial agents
Detergent foods
• Fibrous food in diet prevent lodging of food in pit and
fissure and acts as detergent
Chewing gum
• Chewing gum tend to prevent caries by mechanical
cleaning action
Pit and fissure sealants
• A sealant is a dental resin that is firmly bounded to
enamel surface and isolates pit and fissure from
caries producing conditions in oral environment
• Types:
1st generation – ultraviolet light activated
2nd generation – chemical activated
3rd generation – visible light activated
4th generation – fluoride containing
• Examples of pit and fissure sealants
alphadent
helioseal F
helioseal
Seal – rite
baritone L3
concise white sealant
concise light cure white seal
CONCLUSION
Dental caries is an irreversible process.
It is a disease of modern man and its
manifestation persist throughout life. There
are various methods of control and
prevention of disease. It is always better to
prevent disease. Once occurred it has to
be controlled as it has dangerous sequale.
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