Bridgework Flashcards
What is an abutment
Prepped tooth
Contraindications for bridges
Poor OH
Periodontal disease
Large pulps (conventional)
High possibility of further tooth loss
Large span
Abutment prognosis poor
Tilted teeth
What is a Pontic
Tooth being replaced
What is a retainer
Crown over prepped tooth
Common design for anteriors
Cantilever
Common design for posteriors
Fixed-fixed
Retainer material for a cantilever bridge
CoCr or Nickel Chromium alloy
RRB disadvantages
Can debond
Chipping porcelain
Secondary caries
Metal shine through
RRB advantages
Less surgery time
Minimal/no prep
No LA required
If fails = less destructive
Cheaper
RRB indications
Young teeth
Good enamel quality
Large abutment tooth
Minimal occlusal load
RRB contraindications
Poor enamel quality
Long spans
Bruxists
Tilted/poorly aligned teeth
Direct RRB pontic options
Ideally pts own tooth - remove pulpal tissue
Acrylic denture tooth
Polycarbonate crown
Cellulose matrix with composite
RRB prep
180 degree wrap-around
Rest seats (cingulum/posterior)
Notch on cingulum to help locate
Supragingival chamfer 0.5mm
Anterior prep if required
Minimal
Cingulum undercut removal
0.5mm supragingival chamfer
Notch on cingulum
Posterior prep if required
Occlusal rest
180 wrap around
0.5mm supra gingival chamfer
Temporisation for RRB
Not required
DBA if prep into dentine
Function of sandblasting retainer
Micromechanical retention
Al Oxide 50 microns
Steps of use for PANAVIA - opaque
Etch lingual 30s wash + dry
Re-etch 60s wash + dry
A+B primer for 3-5s for 60s
Evaporate with gentle streams of air
One full turn of PANAVIA until click mix 20s
Place onto metal wing + pressure for 60s
Remove excess at margins
OXYGUARD at margins for 3m then wash off
Pumice + wash
Checks after cementing RRB
Check occlusion + floss contact
Demonstrate OHI w superfloss/ID brushes
Lab card for RRB
Please construct RRB cantilever bridge replacing 14, using 13 as a retainer.
Shade A3
Modified ridge lap pontic
0.7mm metal wing
Conventional bridge design options
Fixed fixed
Fixed cantilever
Fixed moveable
Hybrid bridge
Spring cantilever bridge
Fixed-fixed conventional adv
Can be used for longer span
Max retention + strength
Robust, withstand force
Fixed-fixed conventional disadvantages
Common path of I
Prep must be 5-7 degrees tapered
Prep difficult (parallel required)
Advantages of fixed moveable bridge
Solution for parallelism/diff path of I
Disadvantage of fixed moveable bridge
Only used for replacing 1 tooth
Abutment requirements
Able to withstand forces
No PA/periodontal disease
Crown: root ratio optimum 2:3
Minimum 1:1
Bridgework assessment
MH DH
BPE
Perio
Caries
Parafunction
TTP
Sensibility testing
Xrays
Occlusion + space
Incisor class
Canine/group function
Overeruption
Pontic designs
Wash through
Dome
Modified ridge lap
Total ridge lap
Ovate
Indications for wash through pontic
No contact with Sts
Function>appearance
Lower molars
Indications for dome pontic
Lower incisors/premolars
Indication for total ridge pontic
Greatest contact with ST
Less food packing
Indication for modified ridge pontic
Aesthetics
Food packing lingually
Conventional materials
All metal - gold, nickel, cocr, SS
MCC
All ceramic - Zirconia/lithium disilicate
Ceromeric - belle glass (porc+comp)
Zirconia (LAVA) disadv
Block shade
Decreased aesthetics
Lithium Disilicate (EMAX) adv
Aesthetics
Conventional bridge prep
Pick shade
Occlusal/incisal reduction
Separation
Aim for parallelism
No undercuts
Construct provisional bridge
Take imps + regi
Cement for All metal crown
Aquacem
Relyx luting cement
Cement for MCC
Aquacem
Relyx luting cement
Cement for RRB
Panavia 21 (anaerobic dual cure resin with 10MDP)
Cement for all ceramic
NEXUS (dual cure resin)
Why do we avoid distal pontics?
Occlusal forces on pontic will produce leverage forces on abutment, causing it to tilt
