Dental Caries: Aetiology and Risk Flashcards
7 properties of enamel?
- highly mineralized.
- acellular tissue.
- calcium phosphate crystals (make up 99% of dry weight).
- resemble the mineral hydroxyapatite.
- very hard and brittle.
- not innervated.
- forms white spot lesions when affected by caries.
What is the normal oral cavity pH?
ABOUT pH 7.0.
- Oral fluids supersaturated with hydroxyapatitie and fluoroapatitite.
- Hence these form.
What happens to the oral cavity pH once sugars are metabolized?
pH decreases <4.5<pH<5.5.
- saliva & biofilm become undersaturated with respect to HAp while still supersaturated with respect to FHAp.
- HAp dissolves from subsurface and FHAp forms in surface layers
7 properties of dentine
- 70% inorganic materials
- 20% organic material (90% of which is collagen type 1)
- 10% water
- Due to its elastic properties it is a good support for enamel. Its flexibility prevents brittle enamel fracturing.
- Dentinogenesis begins prior to the formation of enamel
- Initiated by the odontoblasts of the pulp.
- Dentine continues to form throughout life and can be initiated in response to stimuli
What is pulp
An unmineralised tissue composed of soft connective tissue, vascular,lymphatic and nervous tissue.
What are the components of the pulp (3)?
- Cells: fibroblasts and undifferentiated mesenchymal cells (macrophages, lymphocytes, etc.) required for the maintenance and defense of the tissue. Odontoblasts immediately adjacent to the dentin component of the tooth.
- Fibrous matrix: collagen fibers, type I and II
- Ground substance: rich in proteoglycans, glycoproteins and large amounts of water.
2 key organisms for dental caries
- Strep mutans.
- Lactobacilli.
What is Marsh’s ecological plaque hypothesis?
Cariogenic bacteria are ubiquitous in plaque, but usually in concentrations too low to cause problems unless there is a shift in the balance driven by local environmental change.
Success rate of hall technique compared to traditional restorations?
Hall Technique:
- 2 years: 98%
- 5 years: 92%
Composite:
- 2 years: 71%
- 5 years: less than 50%.
GI:
- 2 years: 0%.
- 2 weeks: 20%.
What is the important clinical event in the caries process? Why?
Cavitation is the important event clinically.
The breakdown of the outer enamel makes it difficult to remove the biofilm out of the cavity
What is needed for an effective caries treatment plan?
you need a reliable diagnosis of caries for an effective treatment plan
Achieved via CLEAN, DRY TEETH, WELL LIT, MAGNIFICATION.
What are 2 benefits of early caries diagnosis?
- More management options.
- better outcomes for the patient.
2 disadvantages of using a probe in pits and fissures for checking for caries?
- Poor diagnostic accuracy.
- causes irreversible traumatic defects.
What should be used to check for caries in pits and fissures?
BALL ENDED PROBES.
What is the color of healthy enamel?
Largely transparent (takes on the color of the dentine underneath it).
What does it mean when you etch and the surface looks glossy?
The pores are filled with water and the bone will FAIL!
What is NOT a good indicator of caries progression in dentine?
COLOR.
(unless it is green in which case it is well established and likely active).
3 ways in which caries can be classified?
Site, extent, activity
Dental biofilm in health?
In health, the dental biofilm is constituted of a balanced population of microorganisms of low virulence and cariogenicity
Dental biofilm in disease
With frequent access to fermentable dietary carbohydrates, a dysbiotic microbiological population of high cariogenicity capable of increased production of organic acids promoting dental hard tissue mineral loss forms.
3 most important factors for determining caries risk (predict future caries development)?
- Current/ past disease
- Socioeconomic status
- Intuition
2 advantages of determining a child’s caries risk?
- Allow caries preventive interventions to be targeted at those who need them most.
- Aid selection of the optimum caries management technique for existing carious lesion.
What is used to determine a family’s/ child’s disadvantages level?
Scottish Index of Multiple Deprivation (SIMD).
when should kids see the dentist for the first time?
6 months
