Caries Flashcards
How much can fluoride varnish application decrease caries in primary teeth?
Up to 39%
How much can fluoride varnish application decrease caries in the permanent dentition?
43%
What are the advantages of fluoride varnish?
It is safe.
Accepted by patients and dental staff.
Simple to perform.
Requires minimal training.
The dentist knows the teeth have received fluoride treatment.
What are the disadvantages of fluoride varnish?
It can cause swelling of the oral mucosa, ulcerative gingivitis and stomatitis in a patient that has a tendency towards allergic reactions.
Some may be allergic to colophony.
Contains alcohol.
Some may experience gastric sensitivity.
What is the dose for fluoride varnish for the deciduous dentition?
0.25ml
What is the dose for fluoride varnish for the mixed dentition?
0.4ml
What is the dose for fluoride varnish for the permanent dentition?
0.75ml
What is the aim of fissure sealants?
To prevent caries progression in pits and fissures.
When are fissure sealants indicated?
Poor oral hygiene
Deep fissure pattern
History of caries
Family history of caries
High sugar diet
Special needs
Irregular attender
When is a sealant restoration indicated?
When there is pit and fissure caries confined to one area of the fissure system.
What are the advantages of a rubber dam?
Increases patient comfort.
Prevents moisture contamination.
Retracts and controls soft tissue.
Protects against inhalation, swallowing debris.
Provides optimal visibility.
Controls aerosols.
Excludes salivary borne bacteria from site.
Protects against noxious materials.
What is the definition of caries?
It is a multifactorial, transmissible, infectious oral disease caused primarily by the complex interaction of cariogenic oral flora with fermentable dietary carbohydrates over time.
What is calcium hydroxyapatite?
An inorganic compound composed of calcium, phosphate and hydroxide found in the bones and teeth in a crystalised lattice-like form that gives rigidity.
What aggregations is the plaque made up of?
Bacteria.
Bacterial products.
Pellicle.
How does plaque form?
The pellicle forms on the tooth surface which allows plaque to ‘stick’.
Early colonisers such as streptococcus stick to the pellicle.
Streptococcus create an environment desired by other colonizers.
Later colonisers are porphyromonas gingivalis and actinomyces.
What is demineralisation?
In acidic conditions, S Mutans and lactobacillus generate a high H+ concentration, which causes the loss of minerals such as calcium and phosphate from the enamel.
What is remineralisation?
With no carbohydrates, the bacteria become inactive. The pH increases above 5.5 and the mineral is replaced in the tooth from the saliva. Above 5.5 healthy commensals proliferate. A low H+ concentrate leads to calcium diffusing back into the lesion.
What can effect plaque pH?
Bicarbonate buffering and saliva neutralisation.
What are the histological changes in enamel during caries?
Loos of polysaccharides
Transverse striations
Accentuated lines of Retzius
Dissintegration of enamel prisms.
What is an early caries lesion?
A white spot on the enamel surface.
It is intact.
Can be remineralised.
Describe the Translucent zone in caries.
It lies where the lesion is advancing. It is more porous than sound enamel.
Describe the dark zone in caries progression.
Formed due to demineralisation.
Describe the body of the lesion in caries.
Found between the surface and the dark zone.
Area of greatest demineralisation.
Describe zone 4 in caries progression.
The outer layer of enamel.
Usually not cavitated due to constant remineralisation.
What are the methods of caries detection?
Clinical exam
Transillumination
Detector dye
Separators
Radiographs
What is the pathogenesis of root caries?
Microbial penetration of dentinal tubules occurs.
Dentine starts to dissolve at a higher critical pH at 6.2.
What are the factors associated with root caries?
Reduced saliva volume.
Frequent consumption of carbohydrates.
Lack of fluoride.
Periodontal disease.
Root surface irregularities.
Age
What are the social risk factors associated with root caries?
Living in a nursing home.
Social deprivation.
Infrequent dental attendance.
Manual Worker.
Diet
What are the medical risk factors associated with root caries?
Physical disability.
Dependent on others.
Xerostomia
Cariogenic medicines
How can root caries be prevented?
Prevention of periodontal disease.
Fluoride
Chlorohexidine
OHI
Diet advice
What makes streptococci good initial colonizers in plaque formation?
They are adhesion molecules through electrostatic attraction.
What do streptococci secrete?
Glucotransferase
What do glucotransferases do?
Synthesis glucan from sucrose which creates an acid environment to attract more bacteria.
What is mature plaque more dominant in?
Actinomyces
How can some bacteria survive in an acidic environment?
Increase impermeability to H+ ions.
ATPase pump removes H+ ions.
Produce alkaline to neutralise H+ ions.
Induction of stress proteins
How does fluoride prevent caries?
It forms enamel crystals that are more resistant to acid attacks.
What are the methods of fluoride delivery?
Water fluoridation
Fluoride salt
Fluoride tablets
Fluoride milk/juice
Topical fluoride
Toothpaste
What are the main concerns about fluoride?
Cancer
Down’s Syndrome
Bone Fluorosis
Alzheimer’s
Fluorosis
Freedom of choice.
What are the conclusions on fluoride?
Reduces caries
Reduces inequalities
No clear associations with disease.
What are the advantages of water fluoridation?
Reaches everyone
Cheap
20-40% reduction in caries
Caries increases when it is removed from water supply.
Safe
Consistent
What are the disadvantages of water fluoridation
Mass Medication
Freedom of choice
Complex infrastructure
What are the factors that effect the effectiveness of toothpaste?
Frequency
Concentration
Amount
Rinsing
What is the stepwise technique?
Access
Clear EDJ
Clear base as much as possible.
Lay down calcium hydroxide.
Fill with Gi.
What are the advantages to GI?
Bonds to enamel and dentine.
fluoride release.
Promotes tertiary dentine
What is the criteria for a successful pulp cap?
Absence of symptoms
Normal vitality tests
young patient
Small exposure
No saliva contamination
Pale pink pulp tissue
What is mICDAS?
0 - No change to enamel.
1 - Discolouration/white spot on dry tooth.
2 - white spot on wet tooth.
3 - Inner third of dentine.
4 - Gross cavitation.
When do you not restore a tooth?
Caries free.
Arrested decay.
White spot confined to enamel.
White spot with the loss of some enamel integrity.
Occlusal caries just into dentine.
When is a restoration required?
Pain
Increased caries risk
Rate of progression
Pulp is endangered
Arrest attempts have failed.
Form/function/appearance.
To aid plaque control.
Periodontal health.
