Flashcards in Principles of Cavity Preparation Deck (20)
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1
What determines the design of a cavity
Structure and properties of the dental tissue
The disease present
Properties of restorative materials
2
What must be reviewed and reassessed continually when preparing a cavity
The position of the caries
The extent of the caries
The shape of the prepared cavity
The final restorative material
3
What are the different positions caries can be found in
Pit and fissure
Approximal - posterior and anterior
Smooth surface
Root
4
When should you intervene with caries
If the lesion is cavitated
If the patient can’t access the lesion for prevention
If the lesion is into dentine radiographically
If the lesion is causing a pulpitis
If the lesion is unaesthetic
5
How does dentinal caries usually spread
Laterally along the ADJ
6
When should healthy tooth tissue be removed
If the material used for the restoration requires it
If the margins of the cavity are in contact with another tooth surface
If the margins of the cavity cross an occlusal contact
7
What are the principles of cavity preparation
1) Identify and remove carious enamel
2) Remove enamel to identify the maximal extent of the lesion at the ADJ and smooth the enamel margins
3) Progressively remove peripheral caries in dentine - from the ADJ first then circumferentially deeper
4) Only then remove deep caries over the pulp
5) Outline form modification
6) Internal design modification
8
Describe the properties of a cavity before it is restored
Smooth margins
Appropriate CSMA
No unsupported tooth tissue
No stress concentrator
Internal anatomy that allows adaptation of a material
9
Describe how the first principle of cavity preparation should be carried out
Apply dam
Remove overlying enamel with a high-speed bur to gain access to carious dentine
10
Describe how the second principle of cavity preparation should be carried out
Clear all caries at the ADJ
Check staining at ADJ
Smooth enamel cavo-surface margins
Examine adjacent contact for caries
Avoid trauma to adjacent tooth
11
How should secondary caries be accessed
Use a high-speed bur to remove a restoration
Start from the centre of the restoration and cut towards the edge of the cavity
Remove all the restoration and any underlying base material
Consider waste disposal as materials can be hazardous
12
Describe how the third principle of cavity preparation should be carried out
Detect dentinal caries as a brown stain or softened tissue when using a sharp probe as sound dentine shouldn’t yield under probing
Remove caries first from the ADJ and last from the pulpal flood
13
How should caries from the pulpal floor be removed
Hand-held excavator
Round bur
Chemo-mechanical caries removal
14
Describe how the fourth principle of cavity preparation should be carried out
Decide which restorative material to use
Modify the cavity preparation as appropriate:
Enamel margins CMSA, occlusion internal anatomy, dentine quality
15
What are the most common restorative materials used for direct restorations
Composite
Amalgam
16
What are the advantages of composite (7)
Aesthetics
Conservation of tooth tissue
Support for remaining tooth tissue
Adhesion/bonding
Command cure
Low thermal conductivity
Elimination of galvanism
17
What are the disadvantages of amalgam
Does not bond to enamel or dentine
Does not support the tooth as held into the cavity by retention and resistance form
Need to remove healthy tissue
Not tooth coloured
18
What are the advantages of amalgam
Strong under occlusal load
Less moisture and technique sensitive
19
What should the CSMA be for an amalgam restoration
Between 90-120 degrees
20
