Download File

DENTAL PLAQUE
BY DR. MANISHA MISHRA
1
Dental Plaque
 Yellowish white soft, tenacious, amorphous material deposited on tooth
surface
Formation
Adherent layer of mucinous material from saliva
Colonisation of layers by diffusion of micro organisms
w/n 48 hrs whole layers constitute of microorganisms
2
Plaque deposition occurs in interproximal
surface of posterior teeth i.e,labial and
gingivial for lower and labial and palatal for
upper teeth.
Types:
1. Supragingival
2. Infragingival
Composition:
 70-90%-Microorganisms
 10-30%-Inorganic and Organic substances
3
Dental Plaque
Heavy staining and calculus deposits exhibited on the
lingual surface of the mandibular anterior teeth,
along the gumline.
4
Plaques initially populated by following:
Organisms:
1. Gram positive Cocci/Bacilli
2. Gram negative Cocci and Bacilli
3. Fungus—Candida albican,Actinomycosis
israelli
5
1.Gram positive cocci—
• Streptococcusmutans,viridans,mitis,milleria,salivaris,pyogen
s,Staph- aureus,albus
2.Gram negative cocci—
• NG,NM,NC
3.Gram positive bacilli—
• Lactobacillusacidiphilus,fermentation,odentolyticus
4.Gram negative bacilli—
• H.influenzae,B.pertusis,Fusiform bacteria
6
Other than organisms:
• Inorganic—Calcium,Sodium,
Potassium,Phosphorus
• Organic— Protein,Lipid, desquamated
essential FA,Leucocytosis,Cells.
7
Growth of plaque
 Multiplication of existing bacteria
 Addition of new bacteria
 Accumulation of metabolic products of bacteria
 Food debris from diet
Plaque leads to:
• Acids released from dental plaque lead to demineralization of the adjacent
tooth surface, and consequently to dental caries.
• Saliva is also unable to penetrate the build-up of plaque and thus cannot act
to neutralize the acid produced by the bacteria and remineralize the tooth
surface.
• They also cause irritation of the gums around the teeth that could lead to
gingivitis, periodontal disease and tooth loss.
• Plaque build up can also become mineralized and form calculus (tartar).
8
Inadequate removal of
plaque caused a build up of
calculus (dark yellow color)
near the gums on almost all
the teeth.
DENTAL PLAQUE
9
Prevention
1. Mechanical – Brushing , Flossing
• Brush your teeth twice daily using a fluoride-based
toothpaste.
• Floss your teeth daily, or use an interdental cleaner.
2. Chemical – Mouth wash
3. Food intake –
• Coarse, Dry (Avoid 3s sweet, sticky, soft)
• Eat a balanced diet.
• Avoid using tobacco products.
• Limit the number of snacks you eat throughout the day.
4.Gingival massage
10
Dental Calculus (TARTAR)
• Hard deposit formed on the tooth (due to mineralisation of dental plaque)
• Plaque converted to calculus in 50 – 60 days
Classification
• Supragingival – coronal to gingival margin
• Subgingival – below the crest of gingival margin
11
Supragingival calculus:
• Colour=Yellowish to white ,Blackish
• Consistency=clay like
• Maximum occurs in Upper buccal region of
molar teeth,lingual and interproximal surface
of lower to anterior teeth.
Subgingival calculus:
• Dense brown to greyish black in colour
12
13
Composition:
• 70-90%=Inorganic material
• 10-30%=Organic material
Calculus formation can result in a number
of clinical manifestations:
including bad breath
receding gums and
chronically inflamed gingiva.
14
Prevention
• As in Plaque (oral hygiene)
Treatment
• Scaling
1. Manual and
2. Ultrasonic scaling
15
DENTAL CARIES
16
Dental caries
 Irreversible progressive bacterial damage to the hard structures of the tooth
characterised by demineralization resulting in the formation of a cavity
Etiology
--Decalcification by bacterial acid followed by destruction of all other tooth
tissue
 No theory is universally accepted
 Acidogenic theory
 Proteolysis chelation theory
 Proteolytic theory
17
18
Acidogenic theory
Dental caries is a sugar-dependent infectious disease.
 Acid is produced from metabolism of carbohydrate by plaque
bacteria, which results in a drop in pH at the tooth surface.
 In response, calcium and phosphate ions diffuse out of
enamel, resulting in demineralization.
 This process is reversed when the pH rises again.
 Caries is therefore a dynamic process characterized by episodic
demineralization and remineralization occurring over time.
 If destruction predominates, disintegration of the mineral
component will occur, leading to cavitation.
19
Proteolytic theory
In addition to acid, proteolytic substances
produced by plaque bacteria breakdown the
organic portion of enamel and dentine
20
Proteolysis Chelation theory
Bacterial attack on enamel is initiated by
keratinolytic bacteria causing breakdown of
enamel protein
Organic and inorganic portion of enamel
undergoes demineralization by formation of
chelates
21
22
Saliva and caries
 Saliva acts as an intra-oral antacid, due to its alkali pH
at high flow-rates and buffering capacity.
 In addition saliva:
 ⇓ plaque accumulation and aids clearance of foodstuffs.
 Acts as a reservoir of calcium, phosphate, and fluoride ions,
thereby favouring remineralization.
 Has an antibacterial action because of its IgA, lysozyme,
lactoferritin, and lactoperoxidase content.
23
CARIOGENIC BACTERIA:






Streptococcus mutans
Streptococcus viridans
S. salivaries
S. mitis
S. sanguis
Lactobacillus
24
Properties of bacteria
 Ability to produce acid by fermentation of sugars
 Ability to polymerise sugars into long chain polysaccharides
which make
 plaque adhere firmly to the tooth surface and
 Bacteria to one another
 Lactic acid (main) and other is acetic acid
25
Prerequisites for development of dental caries
 Dental plaque containing cariogenic bacteria
 Bacterial substrate: sugar
 Susceptible tooth surface
• If pH < 5 then demineralization occurs
26
Enamel caries
 The initial lesion is visible as a white spot. This appearance is
due to demineralization of the prisms in a sub-surface layer,
with the surface enamel remaining more mineralized.
 With continued acid attack the surface changes from being
smooth to rough, and may become stained.
 As the lesion progresses, pitting and eventually cavitation
occur.
27
DENTINE CARIES:
 Dentine caries comprises demineralization followed by
bacterial invasion,
 but differs from enamel caries in the production of
secondary dentine and the proximity of the pulp.
28
Diagnosis
Early diagnosis is important
Good eyesight (and a clean, dry, well-illuminated tooth)
 Whitish or blackish spots
 Cavity
29
Investigation
• radiographs are useful in the detection of occlusal caries.
30
Management
If lesion confined to enamel , institute preventive measures and keep under
review.
If lesion has penetrated dentine radiographically, a restoration is indicated
unless serial radiographs show that it is static.
• Removal of diseased enamel and dentine
• Removal of pits and fissures
• Restoration by filling
– Posterior teeth
• Cement & silver amalgam
– Anterior teeth
• Acid etch technique
• RCT –Root canal treatment
31
Restoration showing amalgam
32
Criteria for restoration:
• Restoration should be watertight
• Form of the tooth should be maintained so
that occlusion is normal
• Pulp should be protected with insulating
cement lining
Prevention
• Maintenance of oral hygiene
– Proper brushing
– Regular scaling
– Avoid soft, sticky and sweet diet
• Reduce bacterial load
– Mouthwash with 0.2% chlorhexidine, betadine
• Denial of substrate to plaque bacteria
– Use saccharine( an artificial sweetener) as bacteria cannot utilize it
• Complete removal of plaque by dentist
– Scaling
34
Fluoride addition
• Inhibits demineralization and promotes remineralization of early caries.
•
Fluoride enhances the degree and speed of remineralization and renders the
remineralized enamel more resistant to subsequent attack.
•
Decreases acid production in plaque by inhibiting glycolysis in cariogenic
bacteria.
• An ⇑ concentration of fluoride in plaque inhibits the synthesis of extracellular
polysaccharide.
35
Systemic fluoride
• Water fluoridation in a concentration of 1 ppm (1 mg F /litre) gives a caries
reduction of 50%.
• Fluoride tablets
– depends upon drinking water content
– 1 tab contains 2.2 mg of Na Fluoride
– <2 yrs : half tab
– 2-12 yrs: 1 tab
– > 12 yrs: half tab
36
• Milk with 2.5-7 ppm F has been tried
successfully.
• Salt is cheap and effective for rural
communities in developing countries where
water fluoridation is not feasible
Fluorosis (or mottling) occurs due to a long-term excess of fluoride.
•
It is endemic in areas with a high level of fluoride occurring naturally in
the water.
• Clinically, it can vary from faint white opacities to severe pitting and
discoloration.
38