Rest: Indirect Restorations Flashcards
Includes crowns, bridges, veneers, luting agent, inlays, onlays, ceramics. (92 cards)
INDIRECT RESTORATIONS
What are the five treatment options for treating an edentulous space ?
- Accept.
- RPD or modified Essix retainer.
- Bridge.
- Implant.
- Close space with orthodontic treatment.
What are the benefits of treating an edentulous space ?
Function. Occlusal stability. Speech, Aesthetics. Psychological.
What are the indications for bridges ?
Epileptics. Good OH. Good diet. No active disease - caries/PD.
What are the features of a good abutment tooth for a bridge ?
Large tooth.
Good enamel quality.
Heavily restored and requiring crown.
Favourable angulation.
Favourable occlusion.
Good bone levels.
No PA pathology or successfully RCT’d.
Large roots.
What are the contra-indications for bridges ?
Possibility for future tooth loss.
Abutments of poor prognosis.
Loss of ridge and soft tissues.
Large length of span.
Tilting of abutment teeth.
Poor PA status - unstable.
Significant bone loss - <50%.
Small roots of abutment.
What are the contra-indications for a resin-retained bridge ?
Long span.
Soft tissue loss.
Tilting of abutment teeth.
Bruxists/heavy occlusion.
What are the indications for a resin-retained bridge ?
Replacement of single tooth.
Temporary measure until implant placement (hypodontia).
Tooth with minimal occlusal load.
Large abutment tooth surface area.
Young patients with large pulps.
What are the possible advantages of a resin-retained bridge ?
Low cost/time.
No LA required.
Can be used as temporary measure until implant placement.
Minimal tooth prep required.
What are the possible disadvantages of a resin-retained bridge ?
Risk of debonding.
Metal shine through abutment tooth.
Chip porcelain.
No trial period possible.
What can cause a resin-retained bridge to debond ?
Poor moisture control during cementation.
Heavy occlusal contact.
Secondary caries.
Deterioration over time of materials.
Poor lab technique - poor fit.
Poor retentive components i.e. wings.
What are the advantages of a fixed bridge ?
Robust.
Maximum retention and strength.
Straight forward lab technique.
What are the disadvantages of a fixed bridge ?
Difficult operator technique.
Common path of insertion of abutments.
Greater tissue removal required.
What are the indications for a fixed bridge ?
Abutment teeth requiring crowns/replacement.
Longer edentulous spans.
Heavy occlusal interference.
Smaller pulp chambers.
No tilting or angulation of abutment teeth.
BRIDGES
What degree of tapering should the prep for a fixed bridge have ?
4-7 degrees.
What are the advantages of a cantilever design vs. fixed-fixed ?
Easier operator/lab technique.
Less destructive.
What are the disadvantages of a cantilever design vs. fixed-fixed ?
Can only replace short span.
Mesial pontic îs preferred.
Why is a mesial pontic preferred ?
Reduces occlusal load on pontic - more heavy occlusal contacts posteriorly.
What is the benefit of a fixed-moveable bridge ?
Two abutment teeth can have different paths of insertion.
Why are hybrid bridges rarely done anymore ?
High risk of caries formation.
Describe the anterior preparation for resin-retained bridge.
Rest seat - occlusal contact reduction where metal will be (0.7mm).
Cingulum undercut removal.
180 degrees wrap around preparation on palatal/lingual surface.
+/- proximal grooves.
Supragingival chamfer 0.5mm from gingival margin to make cleansable.
SHOULD REMAIN IN ENAMEL.
Describe the posterior preparation for resin-retained bridge.
2mm occlusal rests.
SHOULD REMAIN IN ENAMEL.
BRIDGES
How can the edentulous space be temporised during resin-retained bridge construction ?
Immediate RPD or Essix.
If in enamel - no temporisation is required.
If in dentine - DBA over to reduce sensitivity.
BRIDGES
What two materials can be used for retainer of a bridge ?
CoCr or NiCr.
Both sandblasted with aluminium oxide.
Describe the process of cementation of a bridge.
Isolate the tooth.
37% etch.
Rinse.
Primer.
Air dry for 2 seconds.
Cement with Panavia 21EX.
Remove excess cement.
Place Oxyguard II for 3 mins.
Rinse.
Check occlusion.
Give OH instructions.