Restorations Flashcards
What properties of the sphere cut amalgam alloy are superior to that of the lathe cut alloy?
Carving and handling properties.
Why do you over pack the cavity with amalgam?
To facilitate the removal of the mercury rich layer and to allow anatomical carving.
What is the function of burnishing?
Improves marginal adaptation and smooths amalgam surface
Why would you polish an amalgam restoration?
- improves corrosion resistance
- corrects minor occlusal discrepancies
- reduces plaque retention
What does using a memosil matrix technique ensure?
The restoration fits in the occlusion properly.
What is the function of a matrix band?
- To reproduce the missing tooth contour
- establishes a contact point
- prevents cervical overhang
When does nano leakage if bonded amalgam restorations occur?
When dentine demineralisation is to a greater depth than the bonding resin penetrates.
What are the main disadvantages of resin composite?
- polymerisation contraction
- photophilic
- hydrophobic
- brittle
Why would you use prepolymerised inserts?
To occupy volume to minimise contraction on curing
Why do darker shades of composite take longer to cure?
They absorb more energy
What is the main advantage of a post cure?
Increases surface cross linking and enhances wear resistance.
When performing a class III restoration what steps do you take to try and preserve aesthetics?
Palatal/lingual approach
What is the main cause of a patient requiring a class V restoration?
Poor oral hygiene
What is the restoration material of choice for a class V cavity?
Glass polyalkenoate as it has intrinsic adhesive properties.
The resulting set material of a glass polyalkenoate consists of which two components?
- glass particles
- silaceous hydrogel
