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VENEERS

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INTRODUCTION

HISTORICAL ASPECT

DEFINITION

CLASSIFICATION

INDICATIONS

CONTRAINDICATIONS

MATERIALS AND TECHNIQUES

PROCESSED COMPOSITES

ETCHED PORCELAINS

CASTABLE CERAMICS

VENEERS FOR METAL RESTORATION

REPAIR OF VENEERS

ON TOOTH STRUCTURE

IN METAL RESTORATION

CONCLUSION



INTRODUCTION

One of the greatest assets a person can have is a smile that shows beautiful

natural teeth. When teeth are discoloured, malformed or crooked, there are often

conscious efforts to avoid smiling or causes a hand to cover the mouth or

manipulation of the lips in an unnatural manner to make up for the defect.

Children are especially sensitive about unattractive teeth because of cruel

remarks made by other children. Correction of these types of dental problems can

produce dramatic changes in appearance, which often results in improved confidence,

personality and social life.

The restoration of a smile is one of the most appreciated and gratifying

services a dentist can render. The veneer is a conservative alternative to full coverage

for improving the appearance of an anterior tooth. Veneers have evolved over the last

several decades to become one of esthetic dentistry’s most popular restorations.

DEFENITION

veneer is a layer of tooth coloured material that is applied to a tooth for

esthetically restoring locali!ed or generali!ed defects or intrinsic discolouration.

CLASSIFICATION

"ental veneers can be classified as follows#

$. "irectly fabricated composite resin veneers.

a. "irect partial veneers

b. "irect full veneers

%. &ndirectly fabricated veneers



3. A#enesis of lateral incisor: When lateral incisors are missing, veneer can be used

to develop better coronal form in the canine, thus simulating a lateral incisor.

These may have to be combined with veneers on the central incisor to develop a

more ideal ratio in the relative proportion of the teeth, because the canine is

invisible too wide when positioned ad4acent to the central incisor.

INDICATIONS

$. 5tained 6 defective restoration

%. "iastema

). /ractures

+. ttrition

. dolescent teeth 78arge pulps9

-. "iscolouration

. :alformation

1. :alpositions 7slight9

3. ;oot e2posure

$<. 'rosion6abrasion

CONTRAINDICATIONS

$9 A%aila&le Enamel: There should be enamel around the whole periphery of the

laminate, not only for adhesion but, more importantly, to seal the veneer to the

tooth surface. There should be sufficient enamel for bonding. =ecause bonding

to dentin is generally less retentive than enamel. &f tooth or teeth are composed



predominantly of dentin and cementum, crowning may well be treatment of

choice.

%9 A&ilit' to etc! enamel: deciduous teeth and teeth that have been e2cessively

fluoridated may not etch effectively. They may re0uire special measures to be

successful with porcelain laminator.

)9 Oral !a&its: (atients with certain tooth habit patterns, such as bru2ism, or tooth to

foreign ob4ects habits may not be ideal candidates of veneers.

+9 (i#! caries rate: in patients with high caries rate laminate veneers are

contraindicated.

(ISTOR):

&n $3)<’s "r. Charles (incus used this porcelain veneers to improve the

esthetics of movie stars teeth. >nfortunately he had to use denture adhesive to hold

the veneers in place. &n mid $3 <’s and early $31<’s composite resin laminate

veneers, wit or without a facing evolved.

t first, composite resin was added directly to facial surface of a tooth to

restore fracture, discoloured or malformed incisors in a procedure known as bonding.

The early composites presented with problems like monochromatic

appearance, with staining and a loss of lusture over time. 'arly composite veneers did

not need any tooth preparation and a bulk of material was needed for pleasing

appearance. >nfortunately over contoured restoration lead to gingival inflammation.

5econd evolution of veneers involved development of preformed veneers that

were 4oined to etched tooth structure. Constructing a veneer and bonding it to etched



&mportant factors like patients age, occlusion, tissue health, position and

alignment of teeth and oral hygiene.

ADVANTA*ES OF INDIRECT VENEERS

$. &ndirectly fabricated veneers are much less techni0ue sensitive to operator ability.

Considerable artistic e2pertise and attention to detail are re0uired to consistently

achieve esthetic and physiologically sound direct veneers. &ndirect veneers are

made by a lab technician and are typically more esthetic.

%. =y multiple teeth are to be veneered, indirect veneers usually an be placed much

more e2peditiously.

). &ndirect veneers will last much longer than direct veneers, especially of porcelain

or cast ceramic.

To achieve esthetic and physiologically sound results an inter@enamel

preparation is almost always indicated.

The only e2ception is in cases where the facial aspect of tooth is significantly

under contoured due to severe abrasion or erosion. &n these cases, more roughening

of the involved enamel and defining of the peripheral margins are indicated.

&ntra@enamel preparation 7or the roughening of the surface in under contoured

areas9 before placing veneer is strongly recommended for the following reasons.

$9 To provide for opa0ue, tinting, bonding and6or veneering materials for ma2imal

esthetics without over contouring.



a. "irect partial veneers

b. "irect full veneers

DIRECT "ARTIAL VENEERS

5mall locali!ed intrinsic discolouration or defects that are surrounded by

healthy enamel are ideally treated with direct partial veneers. The outline form is

dictated solely by the e2tent of the defect and should include all of the discoloured

area. >se a coarse elliptical or round diamond instrument with air water coolant to

prepare the cavity to depth of <. to <. mm.

>sually it is not necessary to remove all of the discoloured enamel in a pulpal

direction. Dowever the preparation must be e2tended peripherally to sound,

unaffected enamel. /or the masking of dark stains opa0uing agents 7e.g. Euva 5eal

(. . sealant in which is dispersed an opacifying agent, titanium@dio2ide9 is used if

necessary. The entire defect or stain is removed, and then a microfill composite is

recommended for restoring the cavity.

:ost composites filled primarily with radiopa0ue fillers, such as barium glass,

in addition to being radiopa0ue are also more optically opa0ue with intrinsic marking

0ualities. >se of these types of composites for the restoration of cavities with light

residual stains is most effective and conserves tooth structure.

S(ADE SELECTION

5pecial attention should be given to matching the color of the natural tooth.

"etermine the shade of tooth before the teeth are sub4ected to any prolonged drying,



because dehydrated teeth become lighter in shade as a result of a decrease in

translucency. Eormally color of teeth varies from degrees of gray, yellow, orange

tints. The color also varies with translucency, thickness and distribution of enamel

and dentin as well as age of the patient.

:any manufactures provide shade guide for their specific materials, which

usually are not interchangeable with materials from other manufactures. :ost

composite materials are available in enamel and dentin as well as translucent and

opa0ue shades. *ood lighting, either natural or artificial is necessary when the color

selection is done.

Eatural light is preferred for selection of shades. &f dental operating light is

used, it should be moved away to decrease the intensity, thus allowing the effect of

shades to be seen.

&n choosing the appropriate shade, hold the entire shade guide near the teeth to

determine general color. Then select and hold a specific shade tab alongside the area

of a tooth to be restored. The shade tab should be partially covered with the patients

lip or operators thumb to create the natural effects of shades. The cervical area is

usually darker than the incisal area.

ISOLATIN* T(E O"ERATIN* SITE

&solation of tooth colored restoration can be accomplished with 7$9 ;ubber

dam, or 7%9 Cotton rolls and retraction cords. Contamination of etched enamel by

saliva results in a decreased bond, contamination of composite, results in degradation

of physical properties.



ADVANTA*ES OF DIRECT VENEER

Can be done in one appointment.

&t is less e2pensive.

Can also be used in cases where patient doesn’t have much time for repeated

appointments.

DISADVANTA*ES

&t is very time consuming.

8abour intensive.

DIRECT FULL VENEERS

&ndicated in e2tensive enamel hypoplasia involving anterior teeth.

lso indicated in distema closure.

5everal important factors like patients age, occlusion, tissue health, position and

ad4ustment of teeth and oral hygiene must be evaluated prior to processing full

veneers.

&f full veneers are done, care must be taken to provide proper physiological

contours, particularly in the gingival area, to favour good gingival health. Over

contoured or properly contoured veneers leads to severe gingival irritation. There

is controversy involving the location of the gingival margin of veneer.

5hould it terminate short of the free gingival crest and the answer depends on

individual situation. &f defect of discolouration does not e2tend subgingivally then

the margin of the veneer should not be e2tended subgingivally.

The only logical reason for e2tending the margin subgingivally is if the area if the

area is carious or defective, warranting restoration, or if it involves significantly.



"ark discoloration that prevents a difficult esthetic problem. Eo restorative

material is as good as normal tooth structure and the gingival tissue is never as

healthy when it is in contact with artificial material.

T,o &asic re aration desi#ns e-ist for full %eneers.

$9 window preparation

%9 n incisal lapping preparation.

A $INDO$ "RE"ARATION

This is recommended for most direct and indirect composite veneers. This

intra@enamel design preserves the functional lingual and incisal surfaces of the

ma2illary anterior teeth, protecting the veneers from significant occlusal stress.

window preparation design also is recommended for indirectly fabricated porcelain veneers if the patient e2hibits significant occlusal function and evidenced by

wear facets on lingual and incisal surfaces. =y using a window preparation the

functional surfaces are better preserved in enamel. The design decreases the potential

for accelerated wear of the opposing teeth that could result if the functional path

involves porcelain on lingual and incisal surfaces.

AN INCISAL LA""IN* "RE"ARATION

&ndicates when the tooth being veneered needs lengthening or when an incisal

defect warrants restoration. dditionally, incisal@lapping design is fre0uently used

with porcelain veneers, because it not only facilitates accurate seating of veneers upon

cementation, but allows for improved esthetics along the incisal edge.



"ROCEDURE

This procedure can be indicated when there is enamel hypoplasia involving all

ma2illary anterior teeth, when diastema is present in between the teeth. fter teeth are

cleaned and a shade selection done, isolate the area with cotton rolls and retraction

cords. (repare the cavity preparation on both central incisor with a coarse, rounded

end diamond instrument.

The window preparation is typically made to a depth roughly e0uivalent to

half the thickness of facial enamel ranging from appro2imately <. to <. mm mid

facially and tapering down to a depth of about <.% to <. mm along the gingival

margin depending on the thickness of enamel.

heavy chamfer at the level of the gingival crest provides a definite cavity

margin for subse0uent finishing procedures. :argins are not e2tended subgingivally,

these areas not defective.

The preparation for a direct veneer normally is terminated 4ust facial to the

pro2imal contact e2cept in areas of diastema. To correct the diastema, preparations

are e2tended from the facial onto the mesial surfaces, terminating at the mesio@lingual

line angles.

The teeth should be restored one at a time. fter etching, rinsing, drying,

procedures apply and polymeri!e the resin@bonding agent. (lace composite on tooth in

increments, especially along the gingival margin, to reduce the effects to allow some

freedom in contouring.



5ometimes, if the teeth have tetracycline stains they are much more difficult to

veneer especially if dark banding occurs in the gingival third of the tooth, for much

cases the veneer margins are placed sub@gingivally.

fter cleansing and shade determination, mark the gingival tissue level prior

to tooth isolation on the facial surfaces of the teeth to be veneered by preparing a

shallow groove with a F round carbide bur.

=ecause the cervical areas are badly discoloured and the gingival tissue covers

much of the clinical crown isolation and tissue retraction is accomplished with heavy

rubber dam and no. $% cervical retainer only one tooth is prepared and restored at a

time.

The outline form includes all of the facial surfaces, e2tending appro2imately

<.$ to $ mm cervical to mark indicating the gingival tissue level, and into the facial

embrasures but not including contact areas. s much well supported enamel as

possible should always remain at the incisal ridge to preserve strength, wear

resistance and functional occlusion or enamel.

(repare the tooth i.e., concave, rounded and diamond instrument by removing

appro2imately half of the enamel thickness 7<.) mm in the gingival region to <. mm

in the mid facial and incisal regions9. fter etching, rinsing and drying, apply thin

layer of bonding agent and cure. Opa0uing layer can be applied after this procedure.

pply a gingival shade of composite to cover gingival third of the tooth. =lend the



incisal shade over the middle third and onto the incisal area for proper contour or

colour.

DIRECT VENEER T(EC(NI+UE

:any dentists find that the preparation, insertion and finishing of several

direct veneers at one time is too difficult, fatiguing and time consuming. 5ome

patients become uncomfortable and restless during long appointments. The veneer

shades and contour can be better controlled when made outside the mouth on the cast.

/or these reasons indirect veneers are preferred.

In direct %eneers include t!ose made &':

$. (rocessed composite.

%. 'tched porcelains 7/eldspathic9

). Castable ceramics.

=ecause of superior strength, durability and esthetics, feldspathic

porcelain is by far the most popular material for in@direct veneering.

Cast ceramic veneers offer comparable 0ualities but re0uire e2acting

lab support and the superb marginal fit of these veneers can minimi!e

or eliminate this disadvantage.

&ndirect veneers are attached to enamel by acid etching and bonding

with either a self@cured, light or dual cured resin bonding material.



ETC(ED "ORCELAIN VENEERS

:ost fre0uently used is etched porcelain 7feldspathic9 veneer. (orcelain

veneers etched with . A hydrofluoric acid 7 @$< minutes9. 'tched porcelain veneer

are highly aesthetic, have high bond with etched enamel via resin bonding medium,

stain resistant, periodontally compatible. The incidence of cohesive fracture for etched

porcelain veneer is less than composite veneer.

ADVANTA*ES

$9 Colour@better natural look with good stability

%9 =ond strength

)9 (eriodontal health

+9 ;esistance to abrasion

9 5trength

-9 ;esistance to fluid absorption

9 'sthetics.

DISADVANTA*ES

$9 Time

%9 ;epair@not easily once luted to enamel

)9 Techni0ue sensitive

+9 Colour

9 Tooth preparation

-9 Cast

9 /ragility.



"ROCEDURE

(orcelain laminate veneers re0uire preparation of tooth. &t is minimal and

within enamel 7<. mm9. &deally finish line should be a slight chamfer placed within

enamel at level of gingival crest or slightly subgingival.

STE"S

a9 8abial6facial reduction.

b9 &nterpro2imal e2tension.

c9 &ncisal or occlusal modification.

d9 8ingual reduction.

LA/IAL0FACIAL REDUCTION

$. '2tended reduction is <.) mm, reduction for the incisal half of labial surface and

incisal edge is <. mm.

%. 8V5 depth diamond cutter is used. This stone creates hori!ontal striations or

depth cut grooves on labial surface.

). This diamond comes in % si!es 8V5 Eo.$ 7<.)mm9, 8>5 EO.% 7<. mm9.

+. 5elect appropriate diamond cuter

. *ently draw diamond across the labial surface of the tooth in a depth cuts as

hori!ontal grooves, leaving a raised strip of enamel between.

-. Then remaining enamel must be reduced to these cuts.

. =ulk of reduction should be done wit with a coarse round end tapered diamond

bur. This completes gingival portion of facial reduction while the tip of diamond

establishes a slight chamfer finish line at level of gingiva. 7/inish line should be

at right angle to the gingival margin9.



INTER"RO1IMAL REDUCTION

$. (ro2imal reduction is an e2tension of facial reduction.

%. >sing round end tapered diamond, continue reduction into pro2imal area.

). s the bur is a carried interpro2imal embrasure, it is easy to lift instrument

slightly towards the incisal, creating a step at gingival. This step should be

eliminated since this can create a dark shadow.

+. To correct an uneven finish line, make sure the diamond is parallel wit long a2is

of tooth. These will guarantee that the gingival e2tension in the interpro2imal

area is e0ual to reduction of pro2imal surface at incisal. The pro2imal reduction

should e2tend into contact area but it should stop 4ust short of breaking the contact

when multiple ad4acent teeth are prepared for veneers. The contacts should be

opened to facilitate separation of the dies without damaging the interpro2imal

finish line.

INCISAL REDUCTION

$. The fabrication of a porcelain veneer capping the incisal edge makes placement of

restoration that much easier by virtue of having a definitive step during seating.

%. The reduction should be at least $ mm if it is desired to restore original length.

). (orcelain is stronger in compression than tension. Wrapping the porcelain over

the incisal edge and terminating it on the lingual surface places veneer in

compression during function. slight incisal overlap provides a vertical stop that

aids in proper seating of veneer.

+. :ultiple wheel diamond bur makes <. mm depth orientation grooves in incisal

edge. ;emove tooth structure between grooves with round end tapered diamond.



LIN*UAL REDUCTION

$. Create the lingual finish line with the round end tapered diamond. Dold

instrument parallel to lingual surface, with its end forming slight chamfer <. mm

deep.

%. /inish line should be G$6+ th the way down the lingual surface, $.< mm from

centric contacts and connecting the tow pro2imal finish lines.

). &ncrease strength, increase thickness of porcelain.

IM"RESSIN* MA2IN*

/irst retract with cord or cotton impregnated with astringent like aluminum

sulfate. Heep coard for minutes. &mportant material ? elastomeric@light and heavy.

"ROCESSED COM"OSITE VENEERS

&n recent years, lab processed composites resins have been developed as

indirect veneer material suing light, heat, vacuum, microfilled resin materials can be

processed with better physical and mechanical properties. They are techni0ue

sensitive, operators skill.

ADVANTA*E

5uperior shading capabilities and control of facial contours, because of

microfiled resin, can be polished to a lustrous finish.

DISADVANTA*ES

8imited bond strength.



l newly developed processed composite of the hybrid type, filled with

barium glass and colloidal slice, offers increased bond strength. =ecause it contains

barium glass, a soft radiopa0ue filler, it can be sandblasted and etched in the lab with

a mild concentration 73A to $<A9 of hydrofluoric acid to produce numerous

microscopic undercuts 7etched composites9. This can help in bonding with enamel.

(rocessed composite can be placed easily, finished and polished also replaced

and repaired easily. Therefore mostly placed in children and adolescents in interior

restoration until teeth have erupted and achieved full crown length. 'tched composite

are indicated for patients who e2hibit wear of interior teeth due to occlusal steers.

window preparation design is recommended due to limited bond strength. With bond

end tapered designs at depth of <. m to <. mm then impressions are made.

light cured resin bonding agent is used for bonding. 'tch, rinse and dry the

tooth, this layer of resin bonding agent is applied to etched enamel, lightly blown with

air but not cured until placement of veneers. (remature curing may preclude full

seating of veneers. Veneers are carefully placed on tooth and lightly 4iggled, remove

e2cess bonding medium, cur for +< to -< seconds. Then finishing and flossing is

done.

CASTA/LE CERAMIC VENEERS

$. Castable ceramic@"icor.



%. >nlike etched porcelain veneers, which are fabricated by stacking and fi2ing

feldspathic porcelain, castable ceramics veneers are cast using lost wa2 techni0ue.

). The material is grayish in colour and very translucent.

+. 8ow fusing feldspathic shading porcelains fired onto surface of veneer provides

final coloration.

. (rocedures are same as etched porcelain veneers. '2cept that margins of castable

ceramic veneers cannot be contoured and finished with rotary instrumentation 7it

will lead to loss of coloration9.

ADVANTA*ES

&t has e2cellent marginal fit.

VENEERS FOR METAL RESTORATIONS

$. 'sthetic inserts 7partial or full veneers9 of a tooth coloured material can be placed

on facial surface of a tooth previously restored with a metal restoration.

%. /or new castings, plans are made at time of cavity preparation and during lab

development of wa2 pattern to incorporate a veneers into the cast restoration.

). fter such a casting has been cemented, the veneer can be inserted as described

later, e2cept that the portion of mechanical retention of veneer into casting is

provided in wa2 pattern stage.

VENEERS FOR E1ISTIN* METAL RESTORATIONS

$. Occasionally the facial portion of an e2isting metal restoration 7amalgam or gold9

is 4udged to be distracting.

%. ;adiograph is re0uired, to determine if restoration is sound.



). 5i!e of offensive area determines e2tent of preparation.

+. nesthesia is not re0uired because most of preparation is in metal or enamel.

. Clean areas with pumice, select shade, isolated site with cotton rolls.

-. When offensive metal e2tends subgingivally, the level of gingival tissue is marked

on restoration with a sharp e2plorer and retraction cord is placed in gingival

crevice 7sometimes rubber dam9.

. EO.% carbide bur rotating at high speed with an air water spray is used to

remove metal, starting at a point midway between gingival and occlusal margins.

1. (reparation is make perpendicular to surface appro2imately $ mm deep at

minimum leaving a butt 4oint at cavosurfaces margins.

3. ll of metal along facial enamel is removed and preparation is e2tended into

facial and occlusal embrasures 4ust enough for metal to hide the metal.

$<. The contact area on the pro2imal or occlusal surfaces must not be included in the

preparation.

$$. To complete outline form, preparation is e2tended gingivally appro2imately $ mm

past the mark indicating clinical level of gingival tissue.

$%. :echanical retention is placed in gingival area with a Eo.$6+ carbide bur <.% mm

deep along the gingivoa2ial and linguoa2ial angels.

$). ;etention and esthetics are enhanced by beveling enamel cavosurfaces margin <.

mm wide wit a concise, flame shaped diamond instrument oriented at + degrees

to e2ternal tooth surface.

$+. fter etching rinsing and drying, cavity preparation is completed. Eew adhesive

resin liners containing a chemical called +@:'T capable of bonding composite

to metal may be used.

$ . Composite materials inserted and finished in usual manner.



RE"AIR OF VENEERS

/ailure may be because of breakage, discoloration or wear. Eot necessary to

remove the whole old restoration, light cured composite is used. Veneers on tooth

structure#

$. 5mall chipped areas on veneers can be corrected by recontouring and polishing.

%. /or direct composite veneers should be done with same material used before.

). fter cleaning the area and selecting the shade, roughen the damaged surface of

veneer and6or tooth with concise, round end diamond instrument to form a

chamfered cavosurfaces margin. Or mechanical locks can be placed in material

with small round bur, etch, rinse, dry, bonding agent, cure add composite cure

finish.

INDIRECT "ROCESSED COM"OSITES3 IN T(E SAME MANNER

$. /or porcelain veneers, a mild hydrofluoric 7$<A9 acid preparation suitable for

internal sue must be used to etch fracture porcelain apply rubber dam for gingival

protection frosted appearance on porcelain apply silicone coupling agent to etched

porcelain before boding agent, then add composite and finish. &f large replace

entire porcelain veneer.

FAULT) VENEERS IN METAL RESTORATION

$. Clean teeth with pumice, select shade, isolate, retract.

%. ;emove old restoration wit carbide metal cutting bur.

). (lace retention with a Eo.)) I carbide burG<.% mm deep.

+. (olyester strips between teeth pro2imal surfaces.



. Clean metal with acid.

-. pply +@:'T place directly in prepared surface apply composite.

. 'valuation of width of teeth achieved by boley gauge or other caliper. dd

composite and finish.

CONCLUSION

There is a definite need for an esthetically acceptable conservative treatment

to correct the disfiguring appearance of malformed and discoloured teeth. This type

of dental disturbance can introduce a grave psychologic effect on the patient. With

the use of a specially shaded resin material, a thin plastic veneer and an acid etched

techni0ue and also other laminate veneers like porcelain and ceramic veneers, an

esthetic and functional restoration can be produced that will give the dentist and the

patient consistently acceptable clinical results.

The greatest advantage of this techni0ue is it gives ma2imum esthetic effects

and re0uires minimum or no tooth preparation.

veneers - seveneers minar

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