Caries Causation Tutorial 1 Flashcards
Dental caries definition
Non-communicable, bacterial-associated and lifestyle-associated disease
Describe Dental caries
Dynamic process causing progressive destruction of hard tooth substance (enamel, dentine, and cementum) involving demineralization of inorganic part and dissolution of organic part.
What is dental caries lesion (“cavity”)
Observable effect of disease activity
Define ‘active lesion’
Continues to progress due to disease activity
Describe texture of active lesion
Soft and squishy lesion
Define ‘arrested lesion’
Remaining scar following successful treatment to bring disease into remission
Describe texture of arrested lesion
Often brown or black spot.
If the arrested lesion’s spot is hard, does it need treatment?
It doesn’t need treatment
List the four main risk factors of dental caries
- Dental plaque containing cariogenic bacteria
- Dietary sucrose
- Fluoride insufficiency
- Saliva insufficiency
Describe the steps of carious process
1) Colonies of bacterial (dental plaque/biofilm) adhere to tooth surface.
2) Sugar exposure upsets ecological balance - acidogenic bacteria proliferate
3) Plaque along is insufficient to cause dental caries
Describe process when bacterial plaque is exposed to sugar
- Bacterial plaque exposed to sugar
- Sugar fermented to acid
- Acid trapped against tooth surface by biofilm and diffuses into tooth surface
First sign of caries?
White spot lesion and radiolucency in enamel image
If sugar and plaque remain what forms?
Cavity forms that extend into dentine
Which rots quicker? Dentine or enamel?
Dentine rots much quicker than enamel.
When lesion reaches dentine, patient experiences ?
Experiences pain (dentinal tubules)
Carious lesion can infect enamel, dentine and?
Pulp chamber can get infected
List the minor to severe clinical presentation of caries
1) White spot lesion - sign of dissolving enamel
2) Loss of enamel - pitting and cavitation (sign of lesion in dentine)
3) ‘Hole’ develops
4) Hole gets bigger and bacteria reach pulp (causes abscess)
5) Tooth breaks down - nearly fully loss of crown
6) Totally ruined tooth
Common sites for plaque build-up?
- Gingival margins
- Interproximal spaces
- Within grooves, pits and fissures
- Margins of restorations (e.g. overhangs or deficiencies
Plaque index score = 0
Clean surface
Plaque index score = 1
No visible plaque but can be scraped off with probe
Plaque index score = 2
Visible plaque
Plaque index score = 3
Thick visible plaque
How to record plaque index?
- Measure buccal and lingual surfaces of 16, 11, 26, 36, 41, 46
- Total out of 36
Name evidence that plaque causes white spot lesions
- Bacteria is a necessary but not sufficient cause
- Suitable substrate (e.g. sucrose) is needed as well
- When pH < 4 for two hours, S. mutans, and lactobacilli remain viable while other bacteria are not
Which bacteria predominate in mouth in normal situation?
Non-mutans streptococci and actinomyces
How is dynamic stability achieved in mouth?
Constant demineralization and remineralization occurs
List the bacterial colonizers of newly cleaned teeth?
- S. sanguinis
- S. oralis
- S. mitis
- Actinomyces
S. mutans make up only ___ of population
2%
When pH decreases, ____ bacteria proliferate causing dynamic stability to shift to ______
Acidogenic bacteria; net mineral loss
White spot lesion -> strep. mutans make up about ____ of total flora
30%
List function of saliva
- Buffering
- Rinsing
- Remineralization
- Lubrication
- Immunoglobins
- Enzymes
Describe buffering function of saliva?
Neutralizing acids formed by bacteria
Describe rinsing function of saliva?
Removes food debris from teeth
Describe remineralization function of saliva?
Contains calcium and phosphate ions
Healthy (low) caries experience related with saliva composition are high in which bacteria?
- Neisseria
- Haemophilus
- Fusobacterium
There is association between genetic polymorphisms and risk of dental caries for most salivary proteins.
True
