Cementation Fixed Prosthesis Flashcards
How are fixed bridges classfied?
By type of retention on abutment teeth
What are types of retention for fixed bridge?
Mechanical
Adhesive
What to do when trying bridge?
- Check lab work
- Check condition of temporary bridge and remove
- Clean abutment
- Try in bridge
- Assess for modification
- Adjust if needed
How to assess the lab work prior to trying in?
Match prescription - shape, shade, aesthetic, contour, margin
Any fabrication issues
Check bridge fit in model - assess marginal fit
Check occlusion of casts
Why should you evaluate the temporary bridge?
Check any wear/loss - drifting of abutments
Did pt have any issue w/ provisional
How to remove temporary direct restoration?
Use crown and bridge removal forceps
Adding vaseline to temp bond can make removal multiple units easier
Should provide LA to remove temp?
Ideally not
Speech/ smile best assessed w/o LA
But if tooth vital may be uncomfortable
How clean abutment teeth?
Clean w/ pumice or prophy paste
Take care with soft tissue
Ensure no temporary cement left
What can be used to clean margins?
Op clean rotary tips
How check proximal contacts?
Use floss
What are signs have correct seating of bridge?
Retainer crown margin closed Adjacent marginal ridge level Initial occlusal satisfactory Firm stop when seated No rocking under lateral load
What features should check for satisfactory aesthetics?
Shade Position Size and shape Proportion Contour Symmetry
How check speech?
F and V = incisal edhe
T and S = cingulu,
‘th’ = air escape under potic
How to do occlusal check?
Check lateral and protrusive contacts w/ diff colour to distinguish ICP contact
Adjust non-ICP contacts
Ideal properties of cement?
High compressive/ tensile strength Low viscosity Long working time - quick set Cariostatic Radiopaque Low solubility Biocompatible Adhesion tooth and restoration
What are 3 main different types of cements?
Acid/ base cements
RMGICs
Polymeric resins
Examples of acid/ base cements?
Zinc phosphate
Zinc polycarboxylate
Glass ionomer
Example of polymeric resin cements?
Self etching resin
Hydrophilic resins
Hydrophobic resins
Issue w/ zinc phosphate cements?
Non adhesive
Low tensile strength
Poor acid resistance
Adv of glass ionomer cements?
Flouride release
Similar adhesion zinc polycarboxylate
Why is RMGIC used as cement?
Tensile and bond strength better GIC
Low film thickness
Good acid resistance
Why are resin cements?
Adhesive and strong
Disadv of resin cements?
Technique sensitive
Adv of hydrophobic resins?
Displace moisture making cementation more predictable
Example of hydrophilic resins?
Panavia
When are hydrophilic resins good to use?
Non-precious metals - high affinity
Primary used adhesive metal bridge
If have metallic indirect restoration what should consider?
If precious or precious metal alloy
If have precious metal alloy what are two types of cementation?
Active cementation
Passive cementation
When is active cementation used?
Type III gold alloy
What cements can be used for passive cementation?
Cement w/ bond to tooth
- Zinc polycarboxylate
- GIC AquaCem
- RMGIC - Rely X luting
- Composite cements - calibra
- Self-adhesive resin composite - Rely X UniCem
What types of cementation can be considered for non-precious alloy bases?
Passive or active cementation
When can active cementation be used in non-precious metal alloys?
Ni-Cr alloys
What consider when cementing ceramic indirect?
If etchable or non-etchable
Examples of non-etchable ceramics?
High strength - alumina or zirconia
How to bond low strength etchable ceramics?
Micromechanical - etch of ceramic w/ HF acid
Silane coupling agent
Composite luting cement
How bond high strength ceramics?
RMGIC
Composite luting cements
