Primciples Of Cavity Design - What Can Go Wrong Flashcards
What 2 things can go wrong?
The restoration itself can fail
The tooth fails
What ways can the restoration fail?
Colour match
Margin intergtity and/ or discolouration
Loss of bulk integrity (chipping)
Can composite restorations shrink?
Yes
How can the tooth fail during a restoration?
Mechanical
Biological
What is mechanical failure?
The tooth essentially breaks
Where can a tooth mechanically fail?
Enamel margin
Dentine margin
Bulk coronal/ cusp fracture
Root fracture
Why can a tooth mechanically fail?
Poor restoration design, crack under surface loads
Introduce surface cracks when preparing the cavity
When placing composite, adhesive shrinkage can put stress on prism of enamel surface, abusing it to be pulled apart at create risk of leakage
When can the dentine margin fail?
Poor moisture control
What are the causes of biological failure?
Secondary caries
Pulp inflammation
Periodontal disease
What are 2 ways to prevent failure?
Cavity design
Placement of restoration
What are 5 essential things for cavity design (prevent failure)?
Ensure caries removed
Design cavity to retain restoration
Ensure adequate depth for restorative material
Cavosurface angle 90 to 110
Don’t leave restoration margins at points of heave occlusal load
What are 3 things which you need to consider with the placement of restoration?
Moisture control
Matrices
Polishing and finishing
