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Faculty of Dentistry
National University of SingaporeFounded 1905
Dr Charles Pincus
“ The development of dental aesthetics in the motion picture industry ”
Journal of the California Dental Association 1938
Faculty of Dentistry
National University of SingaporeFounded 1905
Veneers ( Pincus )• thin facings of air-
fired porcelain• temporarily held in
place with adhesive denture powder
Faculty of Dentistry
National University of SingaporeFounded 1905
Veneers
Direct Indirect(resin)
preformed custom lab (acrylic) fabricated
(resin, ceramic)
CAD - CAM
Faculty of Dentistry
National University of SingaporeFounded 1905
Direct resin bonding• advantages
can be completed in 1 visit under the control of the operator
• disadvantages susceptibility to staining poor wear and abrasion resistance time consuming prone to chipping
Faculty of Dentistry
National University of SingaporeFounded 1905
Indirect veneers
one-piece acrylic resin prefabricated veneer ( Faunce 1970)
laboratory formed microfill resin veneers
chemical primer applied to veneer composite resin to lute the veneer
to etched tooth
Faculty of Dentistry
National University of SingaporeFounded 1905
Indirect prefabricated acrylic and
lab formed resin veneers• display greater anatomical accuracy• less chairside time for dentist and patient• less polymerization shrinkage• better shading capabilities• more control of facial contours• more stain resistant
Faculty of Dentistry
National University of SingaporeFounded 1905
Indirect veneers
Prefabricated acrylic and laboratory formed microfill resin veneers poor resistance to abrasion tendency to delaminate at the
laminate/composite interface limited to cases not involving heavy
functional contacts
Faculty of Dentistry
National University of SingaporeFounded 1905
Indirect Veneers
Porcelain long history of use of porcelain 9th century Chinese 1700 France and England used
refined porcelain for dinner plates and artistic objects
Faculty of Dentistry
National University of SingaporeFounded 1905
Porcelain
• 18th century • Alexis Duchateau• Parisian apothecary• fabrication of denture
bases
Faculty of Dentistry
National University of SingaporeFounded 1905
Porcelain• Dubois de Chemant• patent to manufacture
porcelain denture teeth• 1449 – Dentist’s Supply
Company of New York process for vacuum-firing
porcelain teeth
Faculty of Dentistry
National University of SingaporeFounded 1905
Porcelain Veneers Technique
bonding of thin porcelain laminate to tooth surface using adhesive techniques and a luting composite to change colour, form and/or position of (anterior) tooth
Simonsen & Calamia 1983
Faculty of Dentistry
National University of SingaporeFounded 1905
Porcelain veneers Advantagesdimensional stabilityinsolubility in oral fluidsexcellent aestheticstissue tolerancehigh wear and abrasive resistancelongevity
Faculty of Dentistry
National University of SingaporeFounded 1905
Insolubility in oral fluids• more resistant to deleterious effects of
solvents eg alcohol, medications and cosmetics than resin veneers
Sheth and Jensen 1988
• much less absorption of fluids than any other veneering materials
Garber 1989
Faculty of Dentistry
National University of SingaporeFounded 1905
Excellent aesthetics natural and stable colour optical refractive properties similar to enamel can be intrinsically and extrinsically stained texture easily developed and maintained retains its glazed lustre over the life of the
restoration
Faculty of Dentistry
National University of SingaporeFounded 1905
Tissue tolerance• extremely good biocompatibility with
gingival tissues • less depository areas for plaque
accumulation Olsson et al 1992
• plaque removed more rapidly from porcelain surfaces Hahn et al 1993
Faculty of Dentistry
National University of SingaporeFounded 1905
Physical and mechanical properties
Acceptable tensile bond strength
resin lute – porcelain veneer 2600 – 3200 psiresin veneer – enamel 900 – 1400 psi
Calamia and Simonsen 1984
Faculty of Dentistry
National University of SingaporeFounded 1905
Physical and mechanical properties
Inherent porcelain strength allows reshaping porcelain veneers fragile, once cemented
develops high tensile and shear strengthCalamia
1983
Faculty of Dentistry
National University of SingaporeFounded 1905
Physical properties• exceptional resistance to wear and
abrasion still looks good after many years
• resistant to stain microscopic structure reveals few
voids and irregularities glazed surface
Faculty of Dentistry
National University of SingaporeFounded 1905
Disadvantages of porcelain veneers
• time • difficult to repair• technique - sensitive• colour• irreversible procedure
Faculty of Dentistry
National University of SingaporeFounded 1905
Disadvantages of porcelain veneers
• susceptibility to pitting• difficulty in resurfacing and
polishing glazed surface• fragility• cost
Faculty of Dentistry
National University of SingaporeFounded 1905
Indications for porcelain veneers
• discolorations eg tetracycline, devitalisation, fluorosis, aging, amalgam shine-thru’
• enamel defects eg. aging, cracks, trauma• diastemata - single or multiple• malpositioned teeth• malocclusion
Faculty of Dentistry
National University of SingaporeFounded 1905
Indications for porcelain veneers
• extensive anterior restorations• short teeth• agenesis of the lateral incisor• progressive wear patterns• anterior guide rehabilitations
Faculty of Dentistry
National University of SingaporeFounded 1905
ContraindicationsAvailable enamel not present should be enamel around the whole
periphery of the veneer –for adhesion and seal
optimal bond to enamel Troedson and Derand 1998
Faculty of Dentistry
National University of SingaporeFounded 1905
Contraindications
Bond of porcelain to dentine use of newest generation of DBA the bond strength of porcelain bonded to
enamel > porcelain bonded to dentine Van Meerbeek et al 1996, 1998
Faculty of Dentistry
National University of SingaporeFounded 1905
Contraindications
• ability to etch enamel excessive fluoridation
• oral habits bruxism, pencil chewing or ice-crushing
• occlusion class 3 or end-to-end bite
Faculty of Dentistry
National University of SingaporeFounded 1905
Porcelain veneers• shade selection• tooth preparation• impression• temporisation• laboratory procedures• placement • insertion• finishing• post insertion instructions and
maintenance
Faculty of Dentistry
National University of SingaporeFounded 1905
“ ….. patients may not always know just what they want, but they certainly know what they do not want ”
Faculty of Dentistry
National University of SingaporeFounded 1905
TOTAL TEAMWORK IN
AESTHETIC DENTISTRY
Faculty of Dentistry
National University of SingaporeFounded 1905
Shade selection
• select at the beginning of treatment• use colour corrected lighting and in
daylight• use of opaquer?• single / multiple teeth• refer to lecture on shade taking
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth preparation
To reduce or not to reduce
?
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth reduction• early concepts – minimal or no
preparation led to gingival irritation, overcontouring
and high failure rates Shaini et al 1997 Hahn et al 2000
• current beliefs support removalCalamia 1985Garber 1987
Nixon 1990
Friedman 1991
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth preparation – Rationale• adequate dimension for porcelain• remove convexities and provide path of
insertion• space for opaquing and resin cement• definite seating• receptive surface for etching• facilitate sulcular margin placement
Faculty of Dentistry
National University of SingaporeFounded 1905
Enamel reduction – contraindications
• size of pulp• patient’s psychological
state
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth reduction – how much?
• degree of discolouration• should remain within enamel wherever
possible and especially at the margins• relative teeth position• ceramist’s difficulty working with a thin
veneer
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth reduction
• 0.5 – 0.75 mm to allow for thickness of porcelain
Christensen 1991
• problem with cervical margin – usually encroaches onto the dentine
Ferrari et al 1992
Faculty of Dentistry
National University of SingaporeFounded 1905
Average thickness of enamel on central incisor
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth preparation
• labial• interproximal • sulcular• incisal/occlusal• lingual
Faculty of Dentistry
National University of SingaporeFounded 1905
Sulcular preparation
microleakage increases with• presence of aprismatic enamel
Peumans et al 1999, Tjan et al 1989
• prep encroaches on dentine Zaimoglu and Karaagaclioglu 1991
Faculty of Dentistry
National University of SingaporeFounded 1905
Incisal preparation
• window or intra-enamel• overlapped incisal edge• feathered incisal
Faculty of Dentistry
National University of SingaporeFounded 1905
Tooth preparation
• depth guide• hide margins in embrasure areas• place gingival margin
supragingival just into the gingival sulcus
Faculty of Dentistry
National University of SingaporeFounded 1905
Finish line configuration
• feather edge• rounded shoulder • chamfer -
able to accommodate adequate porcelain
proper seating and accuracy of fit
Faculty of Dentistry
National University of SingaporeFounded 1905
Impression
Tissue management use of retraction cord to displace
gingival tissues cord – haemostatic agent? healthy gingival tissues removal of cord? If yes, remove wet.
Faculty of Dentistry
National University of SingaporeFounded 1905
Impression
• polyvinylsiloxane – light and heavy/ medium viscosity
• insert from buccal oblique direction
Faculty of Dentistry
National University of SingaporeFounded 1905
Temporization
Unnecessary only enamel exposed minimal sensitivity and aesthetic
concerns may irritate gingiva
Faculty of Dentistry
National University of SingaporeFounded 1905
Temporaries – indications• reduction exposing dentine • problem of sensitivity• open contacts allowing movement of
teeth• mandibular teeth with incisal reduction• problem of aesthetics
Faculty of Dentistry
National University of SingaporeFounded 1905
Temporization – techniques• Direct techniques
composite veneer composite resin using vacuform matrix acrylic resin
• Indirect composite resin acrylic resin
Faculty of Dentistry
National University of SingaporeFounded 1905
Temporaries - attachment
• spot etchand/or unfilled bonding agent
• ensure that the periphery of the preparation is not involved or compromised by etching
Faculty of Dentistry
National University of SingaporeFounded 1905
Laboratory Procedures
• a good impression• bite registration• cast of opposing arch• shade selection• photograph ( optional )
Faculty of Dentistry
National University of SingaporeFounded 1905
Laboratory Techniques
• Refractory investment • Platinum foil
Faculty of Dentistry
National University of SingaporeFounded 1905
Refractory investment technique
• porcelain fired directly on a refractory die material
• preferred technique Wildgoose et al
1997
Faculty of Dentistry
National University of SingaporeFounded 1905
Platinum foil technique
• porcelain fired over a 0.001-inch thick platinum foil matrix
• uses individual removable dies on a master cast
Faculty of Dentistry
National University of SingaporeFounded 1905
Porcelain application• use of opaquer ?• built in layers
gingival third body incisal enamel
• finishing and contouring
Faculty of Dentistry
National University of SingaporeFounded 1905
Colour management characterization
• colour changes must be made in the porcelain itself
• communicate using photos• if colour not satisfactory during try-in ,
it is difficult to change
Faculty of Dentistry
National University of SingaporeFounded 1905
Etching of veneers (Lab)
etching inner surface with hydrofluoric acid and silanizing etched surface increases bond strength of a resin lute to etched enamel
Stangel et al 1987
Nicholls 1988
Faculty of Dentistry
National University of SingaporeFounded 1905
Hydrofluoric acid on porcelain
• dissolves glass components
• creates micropores and porosities
Peumans et al 1999Stangel et al 1987 Yen et al 1993
Faculty of Dentistry
National University of SingaporeFounded 1905
Etching of veneer
Using hydrofluoric acid amorphous micro-structure with
numerous porosities increase surface area for bonding micro-mechanical interlocking of the resin
compositeStangel & Nathanson 1987
Faculty of Dentistry
National University of SingaporeFounded 1905
SEM micrograph (magnification X 1000 )
unetched porcelain etched porcelain
Faculty of Dentistry
National University of SingaporeFounded 1905
Etching of veneer
• etching gel – 7.5% hydrofluoric acid• follow manufacturer’s directions
etching time concentration of etchant type of porcelain
Faculty of Dentistry
National University of SingaporeFounded 1905
Silane• chemical coupling agent
between resin and porcelain• improves wettability• increases adhesion• decreases microleakage
Jackson 1994
Faculty of Dentistry
National University of SingaporeFounded 1905
Placement
Try –in each
individual veneer
collective fit assess colour
Faculty of Dentistry
National University of SingaporeFounded 1905
Fit• clean teeth• veneers are extremely fragile• place a drop of glycerine or water• passive fit
Faculty of Dentistry
National University of SingaporeFounded 1905
Cementation
• veneer• tooth surface
Faculty of Dentistry
National University of SingaporeFounded 1905
Colour check
• colour dependent on tooth porcelain composite resin
• use of try-in pastes
Faculty of Dentistry
National University of SingaporeFounded 1905
tooth - RESIN - ceramic
• interface between veneer and tooth surface
• weak link in the system• allow for slight modification of
colour
Faculty of Dentistry
National University of SingaporeFounded 1905
Try in pastes
• avoid exposing resin to operating light• remove try-in paste by placing
veneers in a container of 95% alcohol, acetone or distilled water in an ultrasonic bath
Faculty of Dentistry
National University of SingaporeFounded 1905
Composite Resin Cements
• light curing• chemical curing• dual curing
Faculty of Dentistry
National University of SingaporeFounded 1905
Resin luting agents
• diacrylate resins• particle size : 0.5 - 15 microns• filler loading : 20 - 75 % inorganic
particles• particle type : silica or glass• mostly hybrids , some microfills
Faculty of Dentistry
National University of SingaporeFounded 1905
Composite resin cement for veneers
• a light curing composite resin is preferred longer working time better colour stability
• ensure adequate light transmittance thickness of veneer
Faculty of Dentistry
National University of SingaporeFounded 1905
Thickness of veneer
• thickness of 0.7 mm - resin lute does not reach its maximum hardness
Linden et al 1991
• use of dual curing resin
Faculty of Dentistry
National University of SingaporeFounded 1905
Insertion of veneers• tissue
management• lay out
Faculty of Dentistry
National University of SingaporeFounded 1905
Sequence of cementationveneer tooth(etching) prophylaxissilanation etched
primer
bonding agent cementation
Faculty of Dentistry
National University of SingaporeFounded 1905
Insertion of veneers• seating sequence – central incisors
first • rotate veneer into place with gentle
agitation• do not slide into place• check intimate contact with explorer
Faculty of Dentistry
National University of SingaporeFounded 1905
Polymerization• tack-cure for 5 - 8 secs• remove excess with brush moistened
with bonding resin• cure for at least 2 minutes each
use of 2 lights – buccal and lingual use of 13 mm diameter light tip
Faculty of Dentistry
National University of SingaporeFounded 1905
Finishing• after finishing of veneers, a
considerable amount of excess cement is still present
Harasani et al 1991• removes
marginal defects glaze of porcelain
Faculty of Dentistry
National University of SingaporeFounded 1905
Finishing and polishing
• finish equal or superior to glazed porcelain ( Haywood et al 1988) use of a series of finishing grit diamonds
(MFS) followed by a 30-fluted carbide bur diamond polishing paste
• polish under water spray (Haywood et al 1999)
Faculty of Dentistry
National University of SingaporeFounded 1905
Occlusal assessment
• ensure veneers do not make excessive contact with opposing arch
• use of a night-guard highly recommended
Faculty of Dentistry
National University of SingaporeFounded 1905
Directly milledceramic inlays and onlays
CAD-CAM systems
Computer-aided design /computer aided manufacture
Faculty of Dentistry
National University of SingaporeFounded 1905
CAD –CAM Systems
• Sopha Bioconcept Francois Duret
• DentiCAD Dianne Rekow• Cerec Mormannn and
Brandestini
Faculty of Dentistry
National University of SingaporeFounded 1905
Cerec System ( Siemens)• 1985• clinical track record• fabrication of inlays, onlays and
veneers, ¾, 7/8 and full crowns• Cerec, Cerec 2, Cerec 3
Faculty of Dentistry
National University of SingaporeFounded 1905
Cerec• preparation design• optical impression• computer-generated restoration
design• milling procedure• clinical placement
Faculty of Dentistry
National University of SingaporeFounded 1905
Celay System(Mikrona technologie AG,
Germany)• Stefan Eidenbenz 1994• tooth preparation• impression• pro-inlay fabricated• copied and reproduced in ceramic
in a milling machine
Faculty of Dentistry
National University of SingaporeFounded 1905
Celay system
2 aspects of the milling centreceramic block is centred in holder for manual scanning
rotary turbine with various cutting tools for cutting the replica of the plastic prototype
Faculty of Dentistry
National University of SingaporeFounded 1905
Maintenance
• immediate• long term
Faculty of Dentistry
National University of SingaporeFounded 1905
Post treatment care
First 72 -96 hours avoid hard foods, alcohol and some
medicated mouthwashes avoid extremes in temperatures maintain soft diet
Faculty of Dentistry
National University of SingaporeFounded 1905
Maintenance• routine cleanings
• avoid ultrasonic scaler and air abrasion systems
• use soft toothbrush with rounded bristles• floss• toothpaste – less abrasive • mouthrinses – avoid acidulated fluoride
rinses
Faculty of Dentistry
National University of SingaporeFounded 1905
Maintenance• avoid bad habits – pencil chewing , nail
biting• avoid biting hard foods
biting crab shells sugar cane ice chewing
• use mouth guard with any contact sports
Faculty of Dentistry
National University of SingaporeFounded 1905
Maintenance• avoid
staining foods and liquids eg tea, coffee
• intrinsic erosion – eating disorders
• extrinsic erosion – acidic juices and fruits
Faculty of Dentistry
National University of SingaporeFounded 1905
Failures• most common – fracture
modest 0 - 5% to 7 – 14%Peumans et al 2004Seymour et al 2001Friedman 1998
• marginal staining and leakageStrassler and Weiner 1998Pneumans et al 1998
composite – tooth interface due to lack of enamel caused by chromogenic bacteria and organic stains
Faculty of Dentistry
National University of SingaporeFounded 1905
Failures• unfavourable occlusion and articulation• significant parafunction• exposed and large dentine surfaces • partly bonded to underlying CR• Dunne & Miller
1993 Shiani et al 1997
• marginal defects – wearing out of CR lute
Faculty of Dentistry
National University of SingaporeFounded 1905
SUMMARY“ In vitro and in vivo studies indicate
porcelain veneers are strong and durable restorations in the medium to long term when enough intact tooth tissue to bond the porcelain veneer and articulation and occlusion are not pathological ”
Faculty of Dentistry
National University of SingaporeFounded 1905
Longevity• short to medium-term clinical studies • (1-5 yrs) report a low failure rate • (0-5%) due to loss of bonding and
fracture• higher failure rates ( 7 - 14%) for 3 -10
years Peumans et al 2000 (Review)
• 13 - yr study : 96.4% success Strassler 1989
Faculty of Dentistry
National University of SingaporeFounded 1905
Longevity
• 94.4 % at 12 yrsFradeni et al 2005
• 95 % at 5 - 6 yrs 93% at 10 -11 yrs 91% at 12- 13 yrs
Layton & Walton 2007
Faculty of Dentistry
National University of SingaporeFounded 1905
Co-variables for longevity studies
• design of preparation ?depthfinishing of incisal, proximal
• occlusion• presence of composite fillings• materials – type of luting resin, adhesive • method of fabrication ?• vitality
Faculty of Dentistry
National University of SingaporeFounded 1905
Failures
Esthetics 31%Mechanical complications 31%Periodontal support 12.5%Loss of retention 12.5%Caries 6%Tooth fracture 6%