porcelain laminate veneers/ dentistry course in india

Porcelain laminate veneers.

INDIAN DENTAL ACADEMY

Leader in continuing dental education www.indiandentalacademy.comwww.indiandentalacademy.com

Table of contents.

Introduction.Definitions.History.Review of literature.Indications.Contraindications.Case selection for PLV.

www.indiandentalacademy.com

All ceramic systems used for laminate veneers.

Tooth preparation.Impression making.Shade selection.Provisional restoration.


Lab communication.Lab Fabrication.Try- in considerations.Luting of porcelain laminate

veneers.Finishing and polishing Summary.ConclusionReferences.


Introduction.The restoration of the unaesthetic anterior

teeth has always been a problem, involving large amounts of sound tooth substance, with adverse effects on the pulp and gingiva. The establishment of clear parameters for effective, reliable etching to dental enamel and the development of high quality , microfine composite cements led to introduction of composite veneers for masking discoloration.


Unfortunately composites show polymerisation shrinkage staining andpoor wear resistance. The acrylic laminate veneers was an attempt to overcome some of these problems, but the long term results were clinically unacceptable.


Porcelain as a material for veneering was first reported by Horn , using commercially available porcelain built up in layers on a platinum foil matrix adapted to the model of the tooth. Further Calamia described a modified technique using high temperature investments.


Porcelain is readily etched and the application of the silane couplers to the surface overcame the problem of poor bonding found in acrylic veneer.


Definitions.

Veneer: 1. a thin sheet of material usually used as a finish.

2. A protective or ornamental facing.3.Suferficial or attractive display in multiple

layers, frequently termed as laminate veneers.

(GPT 8)


Porcelain laminate veneers: a thin bonded ceramic restoration that restores the facial surfaces and part of the proximal surfaces of the teeth requiring esthetic restorations.

(GPT 8)


History.

1937: Pincus attached thin labial porcelain veneers temporarily with denture adhesive powder to enhance the appearance of Hollywood stars for close-up photographs.

1955: Buonocore introduced the acid etch technique to increase the adhesion of acrylic filling material to enamel.


1958: Bowen developed silica-resin direct filling material.

1975: Rochette mentioned the use of a silane coupling agent with porcelain laminate veneers for repairing fractured incisors.


1976: Faunce and Myers used acrylic resins for preformed laminate veneers.

1983: HORN introduced platinium foil technique.

1983: Calamia introduced refractory die technique.


1983-1984: Calamia demonstrated good bond strengths for hydrofluoric acid etched porcelain, and that the use of silane coupling agent could further increase the bond strength of resin composite to etched porcelain.


Review of literature.


Ron Highton etal.,

A photoelastic study of stresses on porcelain laminate veneers. (JPD 1987;58(2):157-161).

A photoelastic study of four designs for the tooth preperation for porcelain laminate veneers revealed that incisal, labial, proximal and gingival reduction is recommended for patients with class I, division I occlusions.


Although modifications for variant tooth conditions may be necessary, gingival tooth preparation is necessary to control stress distribution and provide the best potential for periodontal health.


Friedman M.(JADA 1987 Dec).

stated that the etch porcelain veneer can provide a restoration that looks natural with minimum tooth preparation. Periodontal response to the veneers , when properly placed has been excellent.


Herbert Victor.

Predictability of color matching and the possibilities for enhancement of ceramic laminate veneers. (JPD 1991;65:619-22).


This study investigated the predictability of color on three illustrated surfaces of the ceramic veneers and the extent to which the laminates may be shade adapted by the use of tints opaquers on the fitting surface.


Conclusion: significance discrepancies were found in the final color match. The dentist should opt for a lighter, more translucent shade, which can be modified before final cementation.


Robert E. Rada.

Porcelain laminate veneer provisionalization using visible light curing resin (QI 1991;22:291-293).


Placement of PLV has become relatively common procedure. Occasionally it is necessary to fabricate provisional restorations.

For these situations, the use of self cure acrylic or composite resin has been described in the literature.


Extensive trimming and finishing procedures are often necessary and due to their inherent fragility they are prone to breakage.

To improve the technique , visible light cure acrylic resins are used for fabrication of direct provisional restorations.


J.J. Linden etal.,

Photoactivation of resin cements through porcelain veneers.( J. Res. Dent 1991;70(2):154-157.


The purpose of the study was to evaluate the effect of porcelain opacity on the curing of composite when porcelain shade and thickness were held constant.

Microhardness testing (KNH) was used to test the degree of cure of each material at various intervels.


Concluded that porcelain opacity did not significantly affect hardness. But the chemical catalyst and prolonged curing times might be essential for clinical success.


Sumiya Hobo

Porcelain laminate veneers with three dimensional shade reproduction. (int dent J;1992:42:189-198.


A new system for creating porcelain veneers with three dimensional shade option is described.

The development of new porcelain consisting of an intense color which provides natural tooth esthetics in layers of only 0.5mm has made this system possible


In addition a masking porcelain may be used over the discolored tooth.

This system claim to supersede the esthetic shade created with other laminate systems, as well as enhancing the marginal integrity of the veneer.


J. G. Wall etal.,

Cement luting thickness beneath porcelain veneers made on platinum foil. (JPD1992;68:448-50).


The purpose of this investigation was to measure the luting space under porcelain laminate veneers that were fabricated on platinum foils cemented on mandibular incisors.


The study demonstrated that required folds in the platinum folds substantially increases marginal discrepancies around the luted veneers.

These discrepancies were apparently smaller than that created with refractory die technique.


S. M. Dunne etal.,

A longitudinal study of the clinical performance of porcelain veneers. (BDJ 1993;175:317-21).


In this study a total of 315 porcelain labial veneers were fitted in 96 patients and were evaluated after a period upto 63 months.

During the evaluation period 17% restorations in 32% of the patients presented with a problem at review.


Increased problem and failure rates were associated with veneers placed on existing restorations, where tooth surface loss occurred prior to the treatment and where inappropriate luting cements were used.


Age , gender, fabrication technique , use of rubber dam were not significant factors.


M. Peumans etal.,

Five year clinical performance of porcelain veneers. (QI1998;29:211-221).

The objective to evaluate overall clinical performance of porcelain veneers evaluated at 5yrs.


Results:93% were satisfactory.7% presented recurrent caries, porcelain

fracture, clinical microleakage and pulpal reaction.

100% retention rate.14% presented excellent marginal

adaptation.www.indiandentalacademy.com

P. A. Brunton.

Tooth preparation techniques for porcelain laminate veneers (BDJ 2000;189: 260-62).

The objective of the study was to determine the effect that two guides (silicone index, depth preparation bur) had on operators ability to appropriately and consistently prepare the teeth for PLV.


Concluded that considerations should be given to the use of a silicone index or depth gauge bur when teeth are prepared for PLV.


David G Wildgoose.

Dimensional change of refractory materials used for ceramic veneers. (Eur. J. Prosthodont. Rest. Dent 2001;9:101-105).


The current literature considers a number of clinical factors which affect the fit of PLV. However , little consideration has been given to the refractory die material and the lab techniques used.


This study found a wide range of dimensional change occurred during setting and firing cycles for 7 refractories recommended for construction of PLV.


It is there fore important that the clinician should consider the suitability of the materials offered by the laboratory, in order to obtain optimum marginal integrity.


Bo-Kyoung Kim

The influence of ceramic surface treatments on the tensile bond strength of composite resin to all-ceramic materials (J Prosthet Dent 2005;94:357-62.)


The purpose of this study was to evaluate the tensile bond strength of composite resin to 3 different all-ceramic coping materials with various surface treatments.


Alumina and zirconia ceramic specimens treated with a silica coating technique, and lithium disilicate ceramic specimens treated with airborne-particle abrasion and acid etching yielded the highest tensile bond strength values to a composite resin for the materials tested.


Christian F.J. Stappert.

Longevity and failure load of ceramic veneers with different preparation designs after exposure to masticatory simulation (J Prosthet Dent 2005;94:132-9.)


This study evaluated the influence of preparation design on longevity and failure load of ceramic veneers bonded to human maxillary central incisors after cyclic loading and thermal cycling in a dual-axis masticatory simulator.


Within the limits of this in vitro investigation, the use of adhesively luted IPS Empress veneers prepared according to the 3 different preparation designs demonstrated adequate stabilization of residual tooth structure.


Crack pattern analysis showed a higher risk of subcritical crack development when the indenter impact was located on the palatal ceramic surface.


Therefore, the palatal contact point position of the antagonist should remain on the natural tooth structure after preparation. In particular, this is important for complete veneer preparations.


George P. Cherukara, Graham R. Davis etal.,

Dentin exposure in tooth preparations for porcelain veneers: A pilot study

(J Prosthet Dent 2005;94:414-20.)


The purpose of this pilot study was to assess the effectiveness of 3 clinical techniques, namely, dimple, depth groove, and freehand, in producing an intraenamel preparation.

The relation between overpreparation beyond the commonly accepted depth of preparation of 0.5 mm and dentin exposure was also examined.


Within the limitations of this pilot study, it was demonstrated that a labial reduction of 0.4 to 0.6 mm resulted in an intraenamel preparation, other than in the cervical region. Even with the use of depth-limiting techniques, a quarter of the prepared labial surface was exposed dentin.


Fernando Zarone

Dynamometric assessment of the mechanical resistance of porcelain veneers related to tooth preparation: A comparison between two techniques.

(J Prosthet Dent 2006;95:354-63.)


The purpose of this study was to detect the stress in maxillary anterior teeth restored with porcelain veneers and compare the resistance to fracture of porcelain veneers prepared using different preparation designs.


Conclusion: The chamfer preparation is recommended for central incisors, whereas the window preparation showed better results for canines. Both preparations can be adopted in the restoration of lateral incisors.


Seok-Hwan Cho,

Effect of die spacer thickness on shear bond strength of porcelain laminate veneers.

(J Prosthet Dent 2006;95:201-8.)


The application of die spacer may affect the shear bond strength (SBS) of porcelain laminate veneer. However, there is no standard for the amount of die spacer necessary for the fabrication of PLV restorations.


The purpose of this study was to evaluate the SBS differences between enamel and a feldspathic PLV as a function of die spacer thickness.


Within the limitations of this study it was found that the appropriate application of die spacer exerts a favorable influence on the SBS of composite-bonded PLV.

The 2-coat application of die spacer provides suitable space to accommodate the cement thickness.


Indications of PLV12,3

1. used in patients who wish to have their anterior dental aesthetic problems corrected in terms of tooth shade, morphology and alignment.


2. if there is sufficient tooth substance for bonding and support, veneers can be used for correcting:

- Tetracycline stains.- Stained non-vital teeth. - unattractive restorations.-enamel fluorosis.- Enamel hypoplasia.- Chipped or slightly worn anterior teeth.- Microdontia.- Minor tooth malalignment.- Closure of midline diastema.


-modifying anterior guidance.-providing undercut zones for removable

prostheses.In adverse clinical situations like

lingual erosion.As substitute for porcelain metals and

crowns, especially in mandibular teeth.


Contraindications.12,3

If there is insufficient amount of enamel for bonding such as in extensive caries and tooth fractures, heavily restored teeth, severe enamel hypoplasia and short clinical crowns.

If excessive forces are acting on the teeth as with active bruxism, and object biting habits.


Darkly stained teeth.Malocclusions.Extensive periodontal bone lossLarge diastemas.


Case selection for PLV.(QI 1995;26:311-315)

Static and dynamic Occlusal relationship.

The usual mode of failure is fracture of the corners, frequently happens at the incisal edges.

The margins should be placed so that they do not contact the opposing dentition during the rest position.


Occlusal interferences and Para functional habits are contraindications for PLV because they result in crack formation.


Periodontal and oral health status:A healthy periodontium forms a strong

foundation on which all the restorative work rests.

It is therefore important to assess the patient's periodontal and oral health before the procedure is begun.


Healthy periodontium.


Mouth breathers who have poor gingival health are poor candidates for porcelain veneers.


Condition of the tooth.

Degree of discoloration:

If the tooth is grossly discolored it may be necessary to bleach the tooth before the veneer is placed.


The discoloration of the tetracycline staining becomes more severe as the enamel reduces.


Extent of caries: if little or no enamel is present after

caries removal placement of veneers is contraindicated.

The veneer –tooth complex is weakened when the surface area of the enamel available for bonding is decreased by 50%.


Extent of restorations:

A restoration if present , should be small enough that the area for bonding with enamel is not compromised.


Quality of the tooth.

Structural defects like amelogenesis imperfecta, dentinogenesis imperfecta are contraindicated.

Large areas of exposed dentin are also unsuitable.


Amelogenesis imperfecta.


Dentinogenesis imperfecte


Large areas of exposed dentin.


Patient’s motivation to maintain.

The patient’s attitude towards the dental health care should be assessed before porcelain veneers are attempted.


Patients expectations.

The patient’s expectations should be realistic.


Oral habits.

Nail or pencil biting is contraindication for veneers because shearing stress may be too great for the ceramics to withstand.


All ceramic systems used for PLV.13,11,1

Conventional (powder- slurry) ceramics.Castable ceramics.Machinable ceramics.Pressable ceramics.Infiltrated ceramics.


Conventional powder slurry ceramics.

These products are supplied as powders to which the technician adds modulator liquid to produce a slurry, which is built up in layers on the die material to form the contours of the restoration.


The powders are available in various shades and translucencies and are supplied with characterizing stains and glazes.


Optec HSP:

Has greater strength than conventional feldspathic porcelain as a result of an increased amount of Lucite.

Because of its increase strength it does not require a core when used to fabricate all ceramic restorations.


The body and the incisal porcelains are pigmented to provide desired shade and translucency.


Advantages.

They fit accurately.Does not require special processing

unit.


Disadvantages.

Increased content of Lucite contributes to high wear of opposing teeth.


Duceram LFC.

Is referred to as “hydrothermal low-fusing ceramic”.

Composed as an amorphous glass containing hydroxyl ions.

Greater density.High flexural strength.Greater fracture resistance.Cause less abrasion against tooth structure.


Restoration is made in two layers:1. Base layer: is a Duceram metal ceramic .Placed on a refractory die using powder

slurry technique and then baked at 930degree C.


2. Second layer: over the base layer , Duceram LFC is applied using powder-slurry technique and baked relatively at 660 degree C.

Material is supplied in different shades .No special lab technique or equipment.


Castable ceramic systems.

Dicor: Polycrystalline glass ceramic material.The fabrication uses lost wax technique

and centrifugal casting techniques similar to those used to fabricate alloy castings.


To achieve appropriate shade , the colorant shades are baked on the surface of the glass-ceramic material.

It is less abrasive to the opposing teeth.


Dentsply introduced Dicor Plus.Which is shaded feldspathic

porcelain veneer applied to the dicor substrate.


Machinable ceramics.

The ceramic ingots used in CAD-CAM restorations donot require further high temperature processing.

They are placed in the machining appartus to produce desired contours.


The different types of systems are:1. Cerec system (Sirona dental systems,

Germany.)This system uses Vita Mark II (Vivdent),

Dicor (Dentsply Int), Procad (Ivoclar North America).


2. Procera AllCeram system (Nobel Biocare).

The procera system involves an industrial CAD-CAM system.


Celay system: in this system the pattern is fabricated directly on the prepared tooth or on the master die, then the pattern is used to mill porcelain restorations.


The restorations produced by these systems produce considerable wide gap between the restoration and the tooth structure.


Pressable ceramics.

1. IPS EMPRESS(IVOCLAR , N. AMERICA)

2.OPTEC PRESSABLE CERAMIC (JENERIC /PENTRON)

3.CERGO-DENTSPLY 4. VITA PRESS-VIDENT


Veneering porcelain IPS Empress- EmpressIPS Empress 2 Empress 2, ErisOptec- optecCergo- Ducera GoldVita Press- Vita Omega


These ceramics offer greater flexural strength when the veneer thickness is not less than 0.5mm.


Infiltrated ceramics.

Composed of an infiltrated core veneered with feldspathic porcelain.

Core is initially extremely porous, and is composed of either Aluminiun oxide or spinel( a composition containing Al2O3 and MgO).

This porous sub structure is subsequently infiltrated with molten gas.

Veneering porcelain-Vitadur alphawww.indiandentalacademy.com

Extremely high flexural strengthStrongest of all ceramic dental

restorations


Disadvantages-core of Al2O3 or spinel is so strong

that traditional internal surface etching is not possible

because of opaque Alumina core , the translucency of the final restoration may not be as life like as with other systems


Stratification method.4

Stratification is a process of forming in layers.

A porcelain veneer that is bonded to the tooth with a resin cement is an example of stratification.


The layers are :

The inner layer – the tooth.The middle layer – the resin cement.The outer layer- the porcelain

veneer.


Various principles are involved in enhancing the color of the porcelain veneers.

The dynamic application of these principles to complex area of porcelain veneer coloration is called stratification method.


Tooth preparation:

Without graded tooth preparation, color control is inconsistent, and over contoured veneers are the rule.


Two levels of graded tooth preparation are necessary to create space.

One level -----> moderate color change (universal preparation).

Another level -----> profound color change.


For Moderate color change , two color change or less, a two plane facial reduction of 0.3 mm in the cervical one third and 0.5 mm in the incisal two thirds is indicated.


For profound color change, three shades or more, all teeth except mandibular incisors, atleast 0.4mm in the cervical area and 0.6mm in the incisal area is indicated.


Resin interface space:

The relationship between light reflection and vitality of the porcelain veneer.

Veneer formed by opaque porcelain ----- masks tooth color ----- limited vitality -------- due to surface light reflection.


Translucent porcelain ------ light transmission and reflection ------ enhances vitality ------ difficult to mask tooth color.


How can porcelain veneers simulate natural teeth?


Using grade resin interface space , to allow resin to dilute tooth discoloration.


Can de accomplished by the use of die spacer.

Two shade change or less


Moderate color change.


THREE SHADE CHANGE OR MORE


Profound color change.


Porcelain veneer formulation.

For a given cast the ceramist should formulate a porcelain veneer that will contain graded opacity appropriate to the desired color change.


Moderate color change ------ translucent porcelain.


Moderate color change.


Profound color change ------- more opaque porcelain.

For polychromatic color gradation veneers are highly characterized.


Profound color change.



Compiled by Dr. VenkatYenepoya Dental College(2004-07)


Table of contents.




Tooth preparation.Impression making.Shade selection.Provisional restoration.Lab communication.


Lab Fabrication.Try- in considerations.Luting of porcelain laminate



Mastique veneer system (L.D Caulk Company) 19

A kit containing several shades of composite resin, laminates.

A large assortment of shapes and sizes of the laminates.


The clear , shell like laminates (0.4mm in thickness) are made of synthetic resin by a pressure and heat cured process.


Veneer primercleaner


Cerestore system: (Johnson and Johnson dental products)7

Shrink free ceramic crown.


This system uses a transfer molding technique to fabricate ceramic crowns directly on the master die with the excellent marginal fit.


Ceramic is flowable at 160deg c and then transferred into the plaster mold by pressure.


Why the ceramic donot shrink?Oxidation of silicone.The silicone resin used as a binder

during transfer molding compensates for the shrinkage of the core material by conversion of siO to siO2 during firing from 160 degree C to 800 degree C.


Composition:Al oxide.MgOGlass frit.Kaolin clay.Silicone resin. (thermosetting, thermoplastic)


Difference between Castable and Pressable ceramics.18,4

Castable ceramics (Dicor) contains tetrasilicafluoroamina crystals.


After the glass casting core is recovered , the glass is sandblasted and the sprues are cut away.

The glass is covered by a protective embedment material and heat treated to cause microscopic plate like crystals (mica) to grow within the glass matrix.

This is known as ceramming.(1350 deg C for 10hrs)


Creamming 1350 deg c for 10hrs.


Ceramming process results in:Increased strenght and

toughnessResistance to abrasion and

thermal shock.The material is less abrasive.


Whereas Pressable ceramics contain higher concentration of Lucite crystals that increase the resistance to crack propagation.


Castable Pressable Infiltrated. Machinable.

Margin quality

Good. Good- excellent

Fair- good fair

appearance.

translucent Slightly translucent

Opaque. Slightly translucent

strenght Weak. Moderately strong

Moderate- very strong

Moderately strong

Acid etchable

Etchable. Etchable. Not indicated

Etchable.


Tooth preparation.1,3,4,5

Objectives of tooth preparation:

1. To provide adequate space for the PLV buildup to prevent over contouring.

2. To allow efficient bonding with less acid-resistant enamel.

3. To create a definite finish line for the technician to fabricate restorations with superior marginal fitting.


4. To provide adequate thickness for porcelian strenght.

5. To allow operator to adapt the veneers more easily to their correct positions.


Usually tooth preparation can be divided into four parts:

1. Labial reduction2. Interproximal extension.3. Cervical margin placement.4. Incisal preparation.


Labial reduction.

The labial reduction of the maxillary teeth should be in the range of 0.3- 0.7mm.


Crispin & Hewlett


Careful depth control is necessary when an even thickness of the enamel is to be removed.

Needed for natural convexities of the labial surfaces.


Nixon porcelain veneer kit II, Brasseler GmbH.


LVS , Brasseler GmbH


Lasco, Chatsworth, CA.


Interproximal extension.

To conceal the finish, the preparation should extend laterally to finish facial to the interproximal contact areas.

If preparation extends on to the lingual side of the contact areas , then undercut zones are created in the cervical areas.


Sorensen etal.,(JPD 1992;67:16-22). found that the mesial and distal

proximal cervical margins of the porcelain veneers have more marginal discrepancies when compared with those of labial surface.


Margin placement.

A well defined chamfer is usually recommended.


Subgingival margin.


Incisal reduction.

GILMOUR AND J.S. GLYDE (BDJ 1988;9-14)

CLASSIFIED THE PREPARATION INTO 4 TYPES


Window or intra enamel preparation with intact incisal enamel.


Feathered incisal preparation labially


Incisal edge preparation to form butt joint lingually.


Incisal edge preparation overlapping lingual surface.


HIGHTON R. etal JPD 1987:58;157-161

Did a photoelastic analysis- showed that incisal overlapping reduce stress in the veneer most

effectively.www.indiandentalacademy.com

Graber etal suggested placement of palatal chamfer-results in increased veneer strength


Tooth preparation in special situations 4

Diastema closure.


Correct proximal preparation


Deficient proximal preparation.


Malpositioned teeth.


Facially tipped teeth.

Desired contour.

Facially tipped.


enameloplastyDesired contour

Lingual deficiencywww.indiandentalacademy.com

Original contourSpace for veneer

Lingual finish line


Post-operative view.


Gingival retraction.3


Impression making.4,5

Materials Rubber base impression materials such

as addition silicones or polyether.


Trays: Custom made or stock full arch impression

trays are used.


Embrasure blockout


Inteproximal tear through margin.


Embrasure blockout.


Intact interproximal extension.


Shade selection.4,5,6

Because ceramic veneers are thin, color from the underlying tooth may alter the final veneer shade.

Without prescribing the background of the tooth to be veneered it is difficult to select the shade of the veneer.


Shade of the prepared tooth.


Shade of the veneers


Provisional restorations.3

Usually not necessary.

In several clinical situations, provisionalization may be required.


If excessive reduction is done to align the tooth.

To prevent supraeruption of the prepared tooth.

If isolated teeth are prepared.High esthetic expectations.


Materials that can be used for provisional restorations:

Acrylics.(SNAP (PARKEL), TEMPLUS (ELLMAN) ,JET (LANG) , DURCALAY (RELIANCE)

Composites.( Revotec, Protemp Grant, Unifast L C)


Techniques :Direct technique.( acrylic, composites)Indirect technique. (acrylic, composites)


Direct technique ( acrylic resin). JPD 1989;2;4;139


BONDING OF PROVISIONAL RESTORATION

Composites.Provisional Non- eugenol cements.


D.A.ELLEDGE etal (JPD 1989;62;139-142)


Direct method using composites:JADA 1995;126:653-656.


Indirect method:(composites) 4


Vacumm Formed provisional coverage4


Position stabilisation using composite resin.4



Compiled by Dr. VenkatYenepoya Dental College(2004-07)


Table of contents.




Tooth preparation.Impression making.Shade selection.Provisional restoration.


Lab communication.Lab Fabrication.Try- in considerations.Luting of porcelain laminate



THINGS NEEDED FOR GOOD COMMUNICATION ARE.4

Laboratory prescription.Pretreatment models.Photographs of the teeth.Accurate impressions.


Lab prescription.

A complete lab prescription consists of the following:

1. shade of the prepared teeth.2. shade of the veneer: cervical, body,

incisal.3. appropriate interface space in die

spacer coats.4. veneer length, contacts, incisal shape.


Shade of the prepared tooth:


Shade gradation of the veneer:


Die spacer: 0.1 mm die spacer for two- shade shift.0.2mm for profoundly stained teeth.


Translucency and opacity levels:Use of highly opaque porcelain gives

non-vital look.Trend is to use translucent and

highly characterized porcelain combined with increased die spacing.


Length, contacts and incisal shape:

Veneer length relative to the prepared tooth.

Contact zone (long or short)Tooth shape( tapered, square)Incisal shape (round, square, variable).


Communication with desired contour and tooth shape.


Lab fabrication.4,5

Platinum foil technique.Refractory die technique.


Platinum foil technique.

Fabricate and use standard stone removable dies.

Platinum foil can be quickly adapted to the die and fabrication started.

Easy to measure the thickness of the veneer during fabrication.


Veneers can be tried on the prepared tooth prior to final glazing.


Disadvantages.

Foil distortion possible.Difficult to assess actual color.Cost of foil.


Stone working model seperating dies


Die spacerwww.indiandentalacademy.com

Platinum foil adapted on the die


APPLY GINGIVAL CERAMICS


Apply dentine porcelain.


Cutting back mesial and distal surfaces for enamel porcelain


Application of enamel porcelain.


Blue stain for mesial and distal borders


Yellow stains on the incisal edges


Completed veneer


The veneers should be colored and glazed prior to foil removal.


Refractory die technique.

Advantages:1. Overall accuracy and fit is generally

better.2. Easier technique.


Disadvantages:1.Requires duplication of stone dies.2.Divestment is required.3.Fit must be verified on stone dies.4.More difficult to control veneer

thickness.


Refractory cast trimmed with stone base.


Dies are placed in the ceramic oven.


Cooled to room temperature and soaked in distilled water.


Application of the opaque layer.


Full contour ceramic buildup.


Contouring the veneers on the dies.


Disc used to cut the veneer away from the die.


Excess is removed from the stone.


Air abraded.


Porcelain etching4,5

Hydrofluoric acid is applied to the fitting surface of the veneer.

Provides good bonding strength by partly dissolving the glassy matrix of the porcelain.


Apply wax to the areas not etched


Internal bonding surface etched with hydrofluoric acid.


Properly etched-foggy appearance


Under etched-shiny appearance


Over etched


Swift B et al., (BDJ 1995; 179: 203-20)Do not place the etched veneers back on

the master cast because it will contaminate their fitting surfaces and adversely affect bonding strength.


Trade names.

Porcelain bonding kit (KHS polymer technologies). 6% HF.

Porcelain etch (Cosmodent) 9.5% HF.Porcelain etchant (Bisco Inc) 4% HF.


Veneer try-in. 4,5,3


Initial veneer inspection.


Veneer color.

Veneer placed on white towel.


Chair side try- in.

Three steps:1.Dry try-in of individual veneer for marginal

fit.

2.Wet try-in of all veneers collectively with a clear liquid medium, for proximal fit.

3.Resin cement try-in.www.indiandentalacademy.com

Dry try-in for marginal fit.

Place the gingival retraction cord subgingivally to prevent sulcular moisture or bleeding from contaminating the surface.

Try each veneer individually in dry to determine marginal accuracy.


Each veneer is placed dry on the prepared tooth to check marginal fit.


Wet try-in for proximal fit.

Fill the internal etched surface with water soluble glycerin to minimize dislodgement if a vertical position is assumed.

Try veneers on appropriate teeth in sequential manner.

If the veneer resists seating remove the veneer and carefully reduce using microfine diamond bur.


All veneers are seated to check the marginal fit.


Veneer try-in for color and color modifications.


TRADE NAMES OF RESIN CEMENTS.

NEXUS (KERR)

PVS PORCELAIN BONDING KIT(JELENKO)

INSURE (COSMODENT)

COMPOLUTE (ESPE)

VIRIOLINK (VIVADENT)


VENEER LUTING AGENT (BISCO)

RECOVER(TELEDYNE GETZ )

MIRAGE FLC(CHAMELEON)

RELY X VENEER CEMENT(3 M ESPE)


For color evaluation veneers must be placed with the material that optically connects the veneer to tooth for correct color evaluation.

Clear water soluble gel is used.


If the color is acceptable cementation using a clear acrylic is initiated.


If the try-in is lighter than a intended shade.

Use resin cement that is darker or approximately same degree.


If it is darker than the intended shadeMix one part of light opaque resin cement

with ten parts of light translucent resin cement.


If generalised polychromatic shade modification needed

only for a portion of veneer .


High chroma composite tint on inner gingival surface.


Grey tint on the inner incisal third.


Veneer seated with right and left rocking motion to extrude cement laterally


Seating veneer from incisal to gingival forces all tints gingivally


TRANSLUCENT VENEER

OPAQUE VENEER

GINGIVAL TINT PLACED


Cementation and finishing. 4,5,3,1

Good moisture control is necessary.


Gingival retraction. 4

Gingival cords:

•Retraction cord is of great help to prevent contamination from gingival crevice


Gingval cords come in different sizes:

Ultrapak plain and ultrapak E (epinephrine impregnated)

Knitted.# 00,#0,#1,#2.


Fischer’s Ultrapack packers- Small - Regular- Large.


GingiBraid: They are available in both plain and

impregnated types.They are impregnated with 10% pottasium

aluminium sulphate.They are braided.


Available in different sizes:

0(n)0(a)1(n)1(a)


Chemical used: Al chloride, Al sulphate, ferric sulphate, epinephrine.


Gingival retraction instrument is Retracta-Gard.

Bin angle, 0.5mm thick, 3mm wide, light and slender polished shank.


Inserting the retraction cord:


Gingigel.


Veneer preparation.

Ultrasonically clean the veneer in acetone for 5 mins


Dry thoroughly and apply silane coupling agent


Apply a thin film of light cured dentin – enamel adhesive liner to the etched surface of the veneer.

Donot light cure.Place veneers in light protected area.


Tooth preparation.


CLEAN TOOTH WITH PUMICE


Check interproximal contacts of the teeth using metal strips(0.0005’’)


PASSING OF ULTRA THIN DIAMOND COATED METAL STRIP TO LIGHTEN THE CONACTS


METAL STRIP PLACED


LOADING VENEER WITH RESIN CEMENT


SEATING THE VENEER


VENEER CARRYING STICKS(GRAB IT-CHAMELEON DENTAL PRODUCTS)3


EXCESS CEMENT


REMOVING EXCESS RESIN


REMOVING EXCESS CEMENT FROM LINGUAL MARGIN


VENEER TACKED BY LIGHT CURING A SMALL SEGMENT


2-3mm tip


METAL STRIP DRAWN LINGUALLY


REMOVE ANY EXCESS LEFT


CURED RESIN CEMENT EXCESS REMOVE

LONG POINTED 30 FLUTED CARBIDE BUR

SCALER OR CURETTE


FINISHING STRIPS-REMOVE INTERPROXIMAL EXCESS


ADJUST OCCLUSAL CONTACTS


POLISH USING CERAMIC POLISHING RUBBER CUPS


Maintenance of porcelain veneers


Maintenance of porcelain veneers consists of periodic reexamination of the veneers as well as contiguous hard and soft tissue.

Patient receptivity to oral hygiene instructions and post-treatment monitoring is optimal.


It is beneficial to contact patient within 30 days of initial placement.


The soft tissue should be examined.

If the veneer margin has a porcelain ledge, the veneer is over contoured, porcelain surface has been roughened, or extraneous cement flash is still present, a localized gingivitis may persist.


The causative factors for any such gingivitis should be diagnosed and eliminated at this follow- up appointment by recontouring or polishing the porcelain.

The patient should continue to be followed up at 2 weeks interval until gingival tissue is healthy.


If the repeated attempts to resolve a localized gingivitis fail , then the veneer should be removed and replaced.


All the veneer margins should be checked with a sharp explorer along the gingival, proximal and incisal margins.

If any catch occurs a micro fine diamond bur and a 30 fluted carbide bur , following by porcelain polishing paste is used to eradicate it.


If any marginal void is detected , a small diamond bur should be used to make penetration into the void.

The enamel surrounding the void is etched for 30 sec , and a polishable resin which matches the veneer is placed to repair the void.

This resin patch should be highly polished.


Any Occlusal prematurities should be detected and adjusted.

If any interferences present, they should be removed , and the veneer should be polished.


Dental hygienist should not polish the porcelain veneers with any form of pumice to avoid altering surface glaze and roughening the porcelain.

If polishing is required , a silicon polishing wheel followed by a porcelain polishing paste should be used with the surface kept moist.


Scaling around the veneer should be performed as with the natural tooth.


The dental hygienist should not use acidulate fluoride solutions on any porcelain surface.

This will effect the glaze and surface is roughened.


Repair of veneers.

Porcelain fractures will occur ranging from minor cracks to bulk losses of the material.

For minor cracks, the occlusion should be checked, adjustments made as required.


Minor intra porcelain cohesive failures may require recontouring and polishing of the damaged area.


Larger looses of porcelain , together with adhesive failures, will require repair of veneer with fine particle hybrid resin composite restoration, or its replacement.


Summary.


Conclusion.


refereneces

1.CONTEMPORARY FIXED PROSTHODONTICS-:STEPHEN F. ROSENSTEIL(3 Edt.)

2.THE SCIENCE AND ART OF DENTAL CERAMICS:JOHN W. McLEAN(VOL.I AND II)

3.PORCELAIN LAMINATE VENEERS FOR DENTISTS AND TECHNICIANS:ROGER J. SMALES


4.FUNDAMENTALS OF ESTHETICS:CLAUDE R. RUFENACHT

5.CONTEMPORARY ESTHETIC DENTISTRY:BRUCE J. CRISPIN

6.PORCELAIN LAMINATE VENEERS:A PRELIMINARY REVIEW(BDJ 1988:9:9-14)


6.A PROVISIONAL RESTORATION TECHNIQUE FOR LAMINATE VENEER PREPARATIONS:(JPD 1989:62:139-142)

7.ADVANTAGES AND LIMITATIONS OF PLV:(JPD:1990:64:406-411)

8.PREDICTABILITY OF COLOUR MATCHING :(JPD 1991:65:619-22


9.THE SCIENCE AND ART OF DENTAL CERAMICS:J.W.MCLEAN:

(J.OPERATIVE DENTISTRY:1991:16:149-156)

10.REMOVAL OF PARTIAL OR FULLY POLYMERISED RESIN FROM PORCELAIN VENEERSJPD 1993:69:443-444)


11.COMPARISON OF FIT OF PORCELAIN VENEERS FABRICATED USING DIFFERENT TECHNIQUES:IJP 1993:6:36-42

12.CASE SELECTION FOR

PLV:QUINT INT;1995;26;311-315www.indiandentalacademy.com

13.A REVIEW OF ALL CERAMIC RESTORATIONS:JADA 1997:128:297-307

14.FIVE YEAR CLINICAL PERFORMANCE OF PORCELAIN VENEERS:QUINT INT :1998:29:211-221)

15.VITAPAN 3D-MASTER:THEORY AND PRACTICE:QDT:1999;43-53


16.FIVE YEAR CLINICAL PERFORMANCE OF PORCELAIN VENEERS:QUINT INT 2002:33:185-189

17.CROWNS AND OTHER EXTRA-CORONALRESTORATIONS:

PORCELAIN LAMINATE VENEERS:BDJ 2002:193:73-82


18. Science of dental materials- Anusavice.19. Art and science of dentistry- Sturdvent.


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