Bridgework

Question 1

What is an abutment/pontic/retainer

Answer 1

Abutment - Prepped tooth
Pontic - fake tooth
Retainer - crown over prepped tooth

Question 2

Contraindications for bridges

Answer 2

Poor OH/caries/active periodontal disease
Large pulps (conventional)
High possibility of further tooth loss
Large span
Abutment prognosis poor
Tilted teeth

Question 3

Common design for anteriors/posteriors

Answer 3

Anterior: cantilever
Posterior: fixed fixed

Question 4

RRB disadvantages

Answer 4

Can debond
Chipping porcelain
Secondary caries
Metal shine through

Question 4

RRB advantages

Answer 4

Cheaper + quicker
Minimal/no prep/LA
If fails = less destructive

Question 5

RRB indications

Answer 5

Young teeth
Good enamel quality
Large abutment tooth
Single tooth replacement
Minimal occlusal forces - not bruxist

Question 6

RRB contraindications

Answer 6

Poor enamel quality
Long spans
Bruxists - heavy occlusal forces
Tilted/poorly aligned teeth

Question 7

Direct RRB pontic options

Answer 7

Ideally pts own tooth - remove pulpal tissue
Acrylic denture tooth
Polycarbonate crown
Cellulose matrix with composite

Question 8

RRB prep

Answer 8

180 degree wrap-around
Rest seats (cingulum/posterior)
Notch on cingulum to help locate
Supragingival chamfer 0.5mm

Question 9

Anterior prep if required

Answer 9

Cingulum undercut removal +notch
0.5mm supragingival chamfer

Question 10

Posterior prep if required

Answer 10

Occlusal rest
0.5mm supra gingival chamfer

Question 11

Function of sandblasting retainer

Answer 11

Micromechanical retention
Al Oxide 50 microns

Question 12

Steps of use for PANAVIA - opaque

Answer 12

Etch lingual 30s then re-etch 60s
Primer
Evaporate with 3n1
Place PANAVIA onto metal wing + pressure for 60s
Remove excess
OXYGUARD at margins for 3m
Wash off

Question 13

Checks after cementing RRB

Answer 13

Check occlusion + floss contact
Demonstrate OHI w superfloss/ID brushes

Question 14

Lab card for RRB

Answer 14

Please construct RRB cantilever bridge replacing 14, using 13 as a retainer.
Shade A3
Modified ridge lap pontic
0.7mm metal wing

Question 15

Conventional bridge design options

Answer 15

Fixed fixed
Fixed cantilever
Fixed moveable
Hybrid bridge
Spring cantilever bridge

Question 16

Fixed-fixed conventional adv

Answer 16

Can be used for longer span
Max retention + strength
Robust, withstand force

Question 17

Fixed-fixed conventional disadvantages

Answer 17

Common path of I
Prep must be 5-7 degrees tapered
Prep difficult (parallel required)

Question 18

Abutment requirements

Answer 18

Able to withstand forces
No PA/periodontal disease
Crown: root ratio optimum 2:3
Minimum 1:1

Question 19

Bridgework assessment

Answer 19

MH
DH
BPE
Perio
Caries
Parafunction
TTP
Sensibility testing
Xrays
Occlusion + space
Incisor class
Canine/group function
Overeruption

Question 20

Pontic designs

Answer 20

Wash through - lower molars
Dome - lower incisors/premolars
Modified ridge lap - aesthetics, food pack lingually
Total ridge lap - greatest contact with ST (less food packing)
Ovate

Question 21

Conventional bridge materials

Answer 21

All metal - gold, nickel, cocr, SS
MCC
All ceramic - Zirconia/lithium disilicate
Ceromeric - belle glass (porc+comp)

Question 22

Zirconia (LAVA) disadv

Answer 22

Block shade - decreased aesthetics

Question 23

Lithium Disilicate (EMAX) adv

Answer 23

Aesthetics

Question 24

Cement for All metal crown

Answer 24

Aquacem Relyx luting cement

Question 25

Cement for MCC

Answer 25

Aquacem Relyx luting cement

Question 26

Cement for RRB

Answer 26

Panavia 21 (anaerobic dual cure resin with 10MDP)

Question 27

Cement for all ceramic

Answer 27

NEXUS (dual cure resin)

Question 28

Why do we avoid distal pontics?

Answer 28

Occlusal forces on pontic will make abutment tilt