Bridgework 3 Flashcards
alternatives to bridgework
no restoration
denture(s)
implant(s)
holistic tx planning
- Look at the whole mouth
- Not only at a specific tooth
- Plan for retrievability (always have a back-up plan)
- All restorations will eventually fail
- What will be options? Replace like for like? More destructive resort?
- What will the dentition be like in 10-years?
longevity of RBB
80% over 5-10years
longevity of cantilever bridge
80% over 5-10years
longevity of fixed-fixed over 5-10years
90%
collect information when gathering pt history in regards to bridge planning
- History
- Presenting complaint
- Medical and social history
- Past dental history
- attendance, OH
- Clinical examination (Extra- and intra-oral)
- Soft tissues
- Periodontal
- Caries risk assessment
- Occlusion
- Parafunction
- Abutment evaluation
- Remaining tooth structure
- Special tests
- Radiographs
occlusal information for bridgework planning
- Examine:
- Intra-orally
- Study casts
- Facebow-mounted on semi-adjustable articulator
- Incisal classification (ortho lectures)
- Canine-guided or group function?
- Opposing tooth over-erupted?
- Reducing interocclusal space
- Will bridge interfere with current occlusion?
- Will it be changed when bridge placed?
- Signs of parafunction present?
- Wear facets, attrition etc.
- Bruxism – risk of destroying bridge when placed
- Wear facets, attrition etc.
evaluation of potential abutments when designing and planning bridges (8)
- Root configuration
- Big or multi rooted best
- Angulation/rotation of abutment
- Periodontal health
- Surface area for bonding & quality of enamel
- Risk of pulpal damage
- Quality of endodontics:
- Remaining tooth structure present?
- Core
- Remove and rebuild?
options for bridge design (3 main groups with subgroups)
- Resin-bonded/Resin-retained/Adhesive
- Cantilever
- Fixed-fixed
- “Conventional”
- Cantilever
- Fixed-fixed
- Fixed-moveable
- Hybrid
- Spring Cantilever Bridge
Pontic design
5
- Wash-through pontic
- Dome/Bullet/Torpedo
- Modified ridge lap
- Total ridge lap
- Ovate pontic
3 functions of pontic
- restore appearance of missing tooth
- stabilise occlusion
- improve masticatory function
3 considerations for pontic design
cleansability
appearance
strength
cleansability in pontic design
- Should always be smooth, with highly polished or glazed surface
- Surface should not harbour join of metal and porcelain (if metal-ceramic design used)
- Shearing off due to occlusal force
- Embrasure space smooth and cleansable
appaerance for pontic design
anteriorly - as ‘tooth like’ as possible
posteriorly - may compromise
strength for pontic design
longer the span - greater the thickness required to withstand occlusal forces
4 surfaces of pontic
- Occlusal surface
- Resemble surface of tooth it replaces
- Narrower if possible to enable cleaning
- Should have sufficient occlusal contact so can function
- Need driven down long axis of tooth
- Approximal surface
- Connector: strength (roughly 2 by 2 mm for strength)
- Embrasure: space – floss/interdental, but want to try and reduce for aesthetic
- Buccal & lingual surface
- Ridge surface
wash through pontic design
no contact with soft tissue
fucntional rather than for appearance
consider in lower molar area
easy to clean
a.k. hygienic or sanitary
dome shaped pontic design
useful in lower incisor, premolar or upper molar areas
acceptable if occlusal 2/3 of buccal surface visible - poor aesthetics if gingival 1/3 of tooth visible
good for cleaning
a.k.a torpedo or bullet shaped
modified ridge lap pontic design
buccal surface looks as much like tooth as possible
lingual surface cut away
line contact with buccal of ridge
problems with food packing on lingual surface of ridge
ridge lap/saddle pontic design
greatest contact with soft tissue
if designed carefully: can be cleansed
less food packing than ridge-lap
care taken not to displace soft tissue or cause blanching of tissue
ovate pontic design
good for OH good pt
and want optimal aesthetics
presses on gingivae, looks like natural tooth piercing out of ginivae
materials for conventional bridges
- All metal
- Gold
- Nickel/Cobalt chromium?
- Stainless steal
- Metal ceramic
- All ceramic – more likely to #, but starting to rival MC
-
Zirconia – very strong, but less aesthetic than lithium disilicate
- E.g. LAVATM and Procera®
-
Lithium disilicate
- e.g. - E.max
-
Zirconia – very strong, but less aesthetic than lithium disilicate
-
Ceromeric (porcelain with composite), less used
- BelleGlass™
- Vectris®
- Targis® Vectris®
common place for all metal bridges
lower posterior area (gold)
metal ceramic bridges usually
make up the majority of bridges made in UK currently
LavaTM 3M ESPE bridges
Zirconia
- 3 – 4 unit fixed bridge (Maximum span) milled zirconium oxide frame with feldspathic porcelain overlying
- Withstand occlusal forces
- Good aesthetics
- Similar reduction to MCC
zirconia bridge
- GDH&S Fixed Pros lab now producing more all ceramic restorations
- Preparations on casts scanned
- Straűmann© – 7 Series by Dental Wings
- Nobel BioCare © – Series 5
- KATANA© zirconia
- Multi-layered (ML) zirconia
- Ultra translucent multilayer (UTML) zirconia
- Milled
- +/- feldspathic (layer) porcelain on top
implant retained bridges
for
types
large span bridges
screw-retained or cement retained
technique for conventional bridgework
- Mounted study models
- Consider diagnostic wax-up and custom impression tray
- Request laboratory to construct vacuum-formed stent
- Allows checking of reduction during tooth preparation
- Allows construction of provisional bridge
- Select shade
- Laboratory made stent or make pre-operative putty impression for provisional bridge
- Occlusal or incisal reduction
- Separation of teeth
- Aim for parallelism of tapered surface of each preparation
- Example: Preparation of fixed-fixed bridge for 13 12 11
- Prep mesial of 11, then mesial of 13
- Prep distal of 11, then distal of 13
- Prep labial (2-planes) of 11, then labial 13 …..etc
- Example: Preparation of fixed-fixed bridge for 13 12 11
- Confirm parallelism
- Consider retentive features if short clinical crown height or overtapered
- Slots
- Grooves
- Construct provisional bridge (do first before definitive imp)
- Make impression and occlusal registration
- Temporarily cement provisional bridge
- Demonstrate cleaning with Superfloss™
- Write/draw prescription for technician – be specific
- Type of bridge
- Abutment teeth
- Pontic teeth
- Shape of pontic
- Material to be used
parallelism
Consider for fixed-fixed conventional bridge
- Common POI – increased retention
- No undercuts
Paralleling by eye
- Direct vision, one-eye closed
- Large mouth mirror (posteriorly)
- Use of a straight probe like a laboratory surveyor, but in the mouth
Extra-oral survey
- Quick impression
- Pour a model
- Use a laboratory surveyor; useful in long span multiple unit bridges
definitive cementation for all metal conventional bridgework (2 options)
- Aquacem (GI luting cement)
- RelyX™Luting (RMGI luting cement)
defintive cementation for metal ceramic bridgework (2 options)
- Aquacem (GI luting cement)
- RelyX™Luting (RMGI luting cement)
defintive cementation for adhesive/resin-bonded/resin-retained bridgework
Panavia 21 (anaerobic dual cure resin cement with 10-MDP)
10-MDP helps tooth stick to metal work
definitive cementation for all ceramic bridgework
NEXUS®/ NX3 kit (dual cure resin cement)
distal cantilevers
Avoid if possible
- Occlusal forces on pontic –> leverage forces on abutment tooth causing it to tilt
May consider in shortened dental arch, pontic 5, abutment 4
(unopposed/ opposed by denture)
longevity
