Inlay/ Onlay Flashcards
What is inlay?
Intraconoral restoration made indirectly to strengthen and repair posterior teeth
What is onlay?
Similar to inlay but extends over weakened cusps to provide extra protection
Indications indirect restorations?
Alternative to amalgam
Resin not indicated
Conservative type indirect restoration
Why may resins not be indicated?
Size of cavity
Previously failed compoiste
When are inlays indicated?
Low caries rate
MO/DO cavities
Conservative MOD
When are onlay indicated?
Teeth w/ large restoration but sound buccal and lingual walls
Contraindication onlay/ inlay?
Pt w/ poor OH
Excessive loading - bruxism
What materials can be used?
Gold
Ceramic
Resin composite
Adv of gold?
Conservative
Good marginal integrity
Good wear characteristic
Corrosion resistant
What consider when providing gold restoration?
Cost
Poor aesthetic
What can see w/ inlay which can cause fracture?
Wedge effect - cause flexion and stress on cusp
Examples of ceramics?
Feldspathic glass ceramic
Lithium disilicate ceramic
Leutice reinforced
Advantage of ceramic indirect?
Aesthetic
Strength
What consider w/ ceramic indirect restoration?
Technique sensitive
Intra-oral adjustment contraindicated until bonded
Adjustment can compromise aesthetics
How are ceramic restorations fabricated?
Conventional - pressable/casting
CADCAM- chair/lab
Adv of using indirect resin composite?
No polymerisation shrinkage
Preparation guideline for onlay/inlay?
Unique to restoration/cavity - no specific guideline
Must finish on sound tooth tissue
Avoid contact on occlusal contacts
General rules for indirect restoration?
Divergent walls - POI
No undercut
Limit POI
Resistance occlusal force
What avoid when providing ceramic restorations?
Bevel - ceramic would have thin section which would fracture
Two different type of temporary restorations available?
Direct or infdirect
Adv of direct temporisation?
No impression required
No temporary cement
What need for indirect temporisation?
Pre-op impression or lab made shell
Cement of choice for gold restoration?
GIC
Resin cements - panavia/ rely x unicem
How to cement glass ceramics?
Fitting surface tx HF acid
Use silane coupling agent
Resin cement
Causes of failure inlay/onlay?
Bulk fracture - often area cuspal coverage
Marginal breakdown
Why resin cements more prone marginal breakdown?
Not heavily filled - wear more quickly
Most common reason for failure of ceramic?
Fractures and chipping
