Indirect restoration
maximum preservation of tooth structure minimal invasion conservative restorative dentistry one treatment appointment relatively low cost
advantages of direct compost ire resin restorations
no or less polymerization shrinkage better physical /mechanical properties ideal occlusal morphology proximal contouring
advantages of indirect composite resin restorations
composite restoration
build up
cast gold restoration
casting
bevel and flare you bevel for gold inlays to improve burnishability
cavosurface margin
0.5 - 1.0 mm wide bevel to improve marginal fit 0.5mm gingival bevel wide bevel for functional cusp coverage 45 degree to cavosurface
cavosurface margins for gold inlays and onlays
90 degree butt joint margin to ensure marginal strength of restorations
ceramic or composite inlay/onlay
high caries rate young patients esthetics small restorations
contraindications for cast gold restorations
heavy occlusal forces inability to maintain a dry field deep sub gingival preparation
contraindications for indirect tooth colored restorations
when the occlusal outline is extended more than 1/2 of the distance between primary occlusal groove to the cusp tip: capping the cusp tip should be considered
cuspal coverage
correct indication cavity preparation size type finishing handling and application technique curing mode mode of finishing and polishing of the restoration correct occlusion experience
dentist factors influencing the longevity of dental restorations
polymerization shrinkage low fracture and wear resistance
disadvantage of direct composite resin restorations
yes
do larger restorations exhibit more deterioration than moderate and small sized restorations?
yes
do you make a mechanical lock for inlays and inlays?
no you do need to worry about retention so you need to make the cuts big enough
do you need to worry about fracture with gold inlays?
yes you are more concerned with retention than stress
do you want a sharp internal line angle with gold?
au content > 40 wt% noble metal content >60%
high-noble
generally 20 years or more
ho long do cast gold alloys last?
2.0 depth cut to ensure strength
how deep should a ceramic or composite inlay only be?
1.5 mm depth cut to obtain appropriate retention
how deep should a gold inlay onlay be?
higher flexural strength and fracture toughness
how does lithium dislocate compare to ceramic reinforced composite resin?
it is the gold standard the most serviceable dental restoration available cast gold alloys are considered the standard against which other restorative materials are compared clinically in terms of fit, biocompatibility and clinical service
how good is gold?
adhesive cementation required fracture strength as high as that of lithium dislocate when adhesively cemented
hybrid ceramic reinforced composite
large restorations endodontically treated teeth teeth at risk for fracture dental rehabilitation with cast metal alloys diastema closure and occlusal plane correction removeable prosthetic abutment
indications for cast gold restorations
large restorations esthetics
indications for indirect tooth colored restorations
a fixed intracoronal restoration a dental restoration made outside of a tooth corresponding to the form of the prepared cavity which is then luted into the tooth no cusp coverage
inlay definition
more resistant "although overall contact induces breakage load is modest"
is it more or less resistant to sliding/impact induced coaching ?
fabricated by pressure casting or milling ivoclar vivadent ivovlar viva dent
lithium dislocate
strength (fractures) fatigue /degradation wear resistance bond strength chemical compatibility of restorative systems technique sensitivity caries inhibiting effects
material factors influencing the longevity of dental restorations
noble metal content > 25% wt
noble
a partial coverage restoration that restores one or more cusps and adjoining occlusal surfaces or the entire occlusal surface and is retained by mechanical or adhesive means
onlay definition
prep wax wax pattern = sprue casting - type II gold alloy try in burnishing
order of creating a cast
oral hygiene preventive measures compliance of recall oral environment -quality of tooth structure/saliva etc size shape location of the lesion and tooth -number of surfaces vital vs non vital tooth premolar vs molar cooperation during tx bruxism/habit
patient factors influencing the longevity of dental restorations
high strength and toughness low wear of both the restoration and opposing natural tooth chemically nonreactive (no adverse biologic response such as corrosion) restorations can be fabricated by casting, milling, or 3D printing
physical properties of gold alloy
noble metal content <25 wt%
predominantly base-metal
lithium dislocate
pressing
removal of weak enamel a lap sliding fit burnishabilitiy
purpose of gingival bevel
congenital anomalies tooth fracture dental caries wear
rationale for inlay or onlay
restoration failure tooth fracture postoperative sensitivity wear loss of retention secondary caries marginal deficiencies
reasons for failure
mixture of resin and ceramic incorporating of ceramic filler particles into a monomer mixture infiltration of a pre-sintered ceramic network by a monomer mixture restorations can be fabricated by machine - milling
resin nano-ceramic/resin infiltrated ceramic
the difference of the two techniques did not reach statistical significance in order to recommend one technique over the other the selection of the best treatment protocol still remains subjective
was there statistical significance?
occlusally divergent taper 2-5 degrees per wall
what angle should walls be?
low solubility marginal adaption comparale to zinc phosphate fluoride release improved retention higher tensile strength
what are desirable properties of RMGI?
polymers ceramics metals
what are materials for direct restorations?
time consuming (two appointments) extra cost
what are the disadvantages of indirect composite resin restorations?
modified taper diamond
what bur do you use to prep a ceramic inlay?
flat and taper bur tapered fissure bur
what burs do you use for cast gold inlays?
lithium disilicate
what ceramics do you use for direct and indirect restorations?
rounded to prevent fracture
what do line angles need to be like for ceramic or composite?
they create dislodging forces with occlusal forces
what do sloped or rounded edges do?
this combination of low hardness and modules couples with higher toughness enables rapid milling with minimal edge chipping consequences as well as greater ability to cope with sever occlusal contact fatigue loading
what do these properties do?
adhesive cementation HF etching + silane + resin cement adhesive cementation has been shown to increase fracture loads and improve longevity a glass ceramic restoration supported by a composite resin cement withstand higher masticatory forces and demonstrated improved clinical performance
what do you need to attach lithium dislocate?
any type of cement zinc phosphate has been chosen because of its low film thickness RMGI is becoming more popular because of is desirable properties
what do you need to cement cast gold restorations?
2.0 or more
what does the depth of the tooth preparation need to be increased to for gold inlays?
4 year survival rate = 98.17%
what is 4 year surivial rate or lithium dislocate on single crowns?
100%
what is 7year surivial rate or lithium dislocate on partial coverage restorations?
amalgam composite resin glass ionomer
what is a direct restoration?
inlay onlay veneer fixed dental prosthesis (crown/bridge)
what is an indirect restoration?
shoulder + bevel on chamber axial reduction 1.0mm or slightly more
what is gold onlay finish line design?
0.5mm
what is ideal clearance?
2.2%
what is the annual failure rate of direct composite?
2.9%
what is the annual failure rate of indirect composite inlay/onlays?
2mm for ceramic inlay
what is the best isthmus?
finish line design : rounded shoulder (deep chamber) axial reduction 1-1.5 finish line width = 1.0mm
what is the ceramic or composite onlay finish design?
comparable or higher fracture toughness lower hardness and elastic modules
what is the difference btw resin nano-ceramic and porcelain and glass ceramic?
1.5 mm
what is the minimal occlusal reduction for a gold onlay?
2.0 mm occlusal reduction
what is the minimal occlusal reduction for ceramic or composite onlay?
10 year survival rate: 65.3% 11.5 year survival rate: 50% 15 year survival rate: 72%
what is the survival rate of extensive amalgam restorations?
no long term clinical data available 3 yr survival rate - 87.7%
what is the survival rate of extensive composite resin restorations?
high noble alloy
what metals do you use for direct and indirect restorations?
composite resin ceramic reinforced composite resin
what polymers do you use for direct and indirect restorations?
flat perpendicular to the long axis of the tooth
what should pulpal and gingiva floors be?
when the preparation outline is extended 2/3 of this distance or more
when is capping absolutely necessary?
class I restorations
where are gold inlays/onlays not the best?
class II restorations
where are gold inlays/onlays the best?
longer margins and poor cleansibility leads to higher biologic risk stress bearing areas such as cusps and marginal ridges lead to higher mechanical risk
why consider an inlay or onlay?
soft - low stress
ADA type 1
moderate stress , light occlusion onlays and inlays
ADA type II
high stress, full occlusal load crowns, short-span FDPs
ADA type III
extra hard very high stress thin veneer crowns long span FDPs RPDs
ADA type IV
