temporisation Flashcards
What is a provisional restoration?
Prosthesis designed to enhance aesthetics, stabilisation +/ function for a limited period of time, after which its replaced by a definitive prosthesis
What is the difference between temporary and transitional?
Temp- limited and predetermined life span
Transitional- not planned for long term but w modifications can serve for a more extensive period of time
What are the functions of provisional restorations?
Protection
Maintain tooth position
Aesthetics
Diagnosis/prognosis
Mastication
Facilitate plaque control
Assess tooth reduction
Informed consent
Coronal seal during RCT
Control/customise emergence profile of soft tissues
When do you use a provisional restoration?
Routine indirect restoration
Replace indirect restoration
Immediate tooth replacement
Replace tooth after implant placement
Planning aesthetic, occlusal or perio changes before definitive
How can provisional restorations be used diagnostically?
Aesthetic trials- easier to reshape and trim to confirm tooth shape/dimensions
Occlusal trial- confirm ability to tolerate new occlusion
Perio changes- replace overhanging restorations or after crown lengthening until tissues stabilise
What are the types of provisionals?
Chair side (operator)
Lab made (dental technician)
What is polyethyl methacrylate (PMMA)?
Good for lab made
Self/chemical cure (powder/liquid)
Good aesthetics, strength and wear resistance
Easy to repair
Significant exothermic and p. shrinkage
Strong smell
Free monomer can cause pulpal/gingival reactions while setting
What is polyethyl methacrylate (PEM)?
Can be used intra orally
Self/chemical cure (powder/liquid)
Less exothermic and p. shrinkage
Poorer aesthetics, strength, wear resistance
Eg. Snap, Trim
What is Bis-Acrylate (ProTemp)?
Self/chemical/dual cure
Contains Bis-GMA, TEGMA
Good aesthetics, better colour stability
Good wear resistance in adequate thickness
Difficult to repair
Weak in thin section
How is composite used as a provisional?
Mainly fro adhesive preps eg. Veneers, to maintain occlusal contacts and improve aesthetics
Placed w/o bonding agent (spot etch)
Can use conventional but also Telio - more dough-like
How are preformed crowns used as a provisional?
Aluminium, stainless steel, polycarbonate (directa)
Useful if no preop impressions
Difficult to control marginal adaptation
Often require a lot of chairside modification (trimming/crimping)
All can be relined w PMMA/PEM or even Bis-Acryl
How can CADCAM milled be used as provisionals?
Digital dentistry
Intra oral scans
Composite/PEEK/PMMA
V accurate
What temporary luting cements are available?
Zinc oxide Euganol (Temp bond)
Euganol free zinc oxide (Temp bond NE)- useful for resin cements as Euganol can inhibit polymerisation of uncured resins
Temp resin cements- translucent for veneers
Zinc Polycarboxylate
How do you place a preformed crown (aluminium/SS)?
Choose suitable size
Trim and crimp margins to improve seating
Option to reline to improve fit
Check occlusion
Cement into place
Remove excess
How do you place a preformed crown (polycarbonate)?
Choose suitable size
Trim margins to improve seating
Shape to improve appearance
Reline to improve fit, trim excess
Check occlusion
Cement into place
Remove excess
