the esthetic treatment of anterior teeth has always presented a challenge in clinical practice . with the improvement of dental materials ,
many restorative options such as resin composites , all - ceramic crowns , and ceramic veneers became available .
in these circumstances , dentists and patients must choose the best alternative to improve oral condition and esthetic results .
ceramic laminate veneers may be indicated when there is anterior dental wear and enough remaining sound dental structure .
this treatment option has been used due to ceramics color stability , biocompatibility , mechanical properties , and esthetic outcome .
such esthetic treatments , however , must not be conducted without an appropriate restorative planning .
the preparation design and the amount of remaining dental structure have significant effects on load to failure of ceramic veneers .
this concept of planning may be used to assist the cosmetic intervention and develop esthetically beautiful smiles .
therefore , the dentist and laboratory technician must follow a proper protocol to achieve higher clinical success rates .
it is important to emphasize that the clinician should have a good understanding of the ceramic type to establish the appropriate cementation procedure that will contribute to long - lasting restorations .
hence , the aim of this paper is to describe minimum thickness ceramic laminate veneers as a restorative solution to improve the esthetics of the smile .
a 34-year - old female patient with enamel hypoplasia on anterior upper incisors was referred to treatment .
radiographic images and clinical exam were conducted . clinically , enamel hypoplasia and discrepancies in shape , form , and color were observed [ figure 1a  c ] .
diagnostic casts and waxed - up restorations to define shape and form were previously obtained to assist the treatment planning . due to the case characteristics ,
note the compromised esthetics due to enamel hypoplasia and anatomic discrepancies of form , shape , and color .
( c ) close - up view of the right maxillary anterior teeth dental preparation consisted of slightly grinding the incisal edges of the lateral incisors and left central incisor with a # 2135-diamond bur ( kg sorensen , barueri , sp , brazil ) [ figure 2 ] .
enamel surfaces were then polished with sequential aluminum oxide discs from coarse to ultrafine ( 3 m sof - lex , 3 m espe , seefeld , germany ) . at the same appointment ,
in - office bleaching was performed with 35% hydrogen peroxide ( mix one , villevie , joinville , sc , brazil ) following the manufacturer 's instructions [ figure 3 ] .
the teeth preparation was limited to enamel application of 35% hydrogen peroxide gel on the surface of the anterior teeth no provisionals were required due to the minimal preparation performed , with no dentin exposure . on a subsequent appointment after 2 weeks , shade selection was performed and impression taken using retraction cords ( ultrapak cord # 000 , ultradent products inc . ,
this technique was selected to provide gingival sulcus enlargement without using impregnated cords with hemostatic or astringent solutions .
the impressions were taken using a vinyl polysiloxane material ( express xt , 3 m espe , seefeld , germany ) .
the trays were loaded with the heavy - bodied impression material , while the light - bodied impression materials were simultaneously spread on the teeth .
retraction cords in position previously to the impression technique ceramic laminate veneer restorations were fabricated with a lithium disilicate - reinforced glass ceramic material ( ips e.max press , ivoclar - vivadent , liechtenstein ) , using the heat press technique . a layering ceramic ( ips e.max ceram , ivoclar - vivadent ) was further applied to improve the incisal edge optical characteristics [ figure 5a ] .
( a ) completed minimum thickness anterior porcelain laminate veneers restorations on the working cast .
( b ) application of the bonding system the veneers internal surfaces to be bonded were etched with hydrofluoric acid ( porcelain etchant 9,5% , bisco inc . , schaumburg , il , usa ) for 20 seconds , washed under running water , dried with an air syringe , and primed ( porcelain primer , bisco inc .
, schaumburg , il , usa ) . a try - in paste ( relyx veneer try - in , 3 m espe , seefeld , germany ) was used to select the proper color of the luting cement .
the laminate veneers were then washed to remove try - in paste and excess of silane and carefully air - dried .
one coat of the bonding resin of adper scotchbond ( 3 m espe , seefeld , germany ) was applied and light - cured [ figure 5b ] . during the cementation
, veneers were cemented separately one - by - one by conditioning with phosphoric acid and applying the same bonding resin on the tooth surface .
the laminate veneer restoration was bonded with a light - curable resin - based luting agent ( relyx veneer , 3m / espe , seefeld , germany ) .
the light polymerization was performed with a led - curing unit ( radii - cal sdi , bayswater , victoria , australia ) for 30 s from buccal , incisal , mesial , and distal aspects of each tooth .
the final restorative phase was achieved by polishing the marginal areas with a silicone instrument ( rubber point jiffy , ultradent products inc . ,
( a and b ) frontal and close - up views of the anterior teeth after placing the veneers .
( c and d ) frontal and lateral views of the smile ( a ) palatal view of the seated restorations after 10 months .
when ceramic veneers are considered , different restorative approaches have been proposed , depending on the thickness of the veneer and the color of the remaining dental structure . in the case of improving esthetics by changing the form and texture of teeth with no severe discoloration , veneers of smaller thickness may be indicated . after being informed about advantages and disadvantages of each restorative option , the patient opted for the conservative ceramic veneers of minimum thickness . the long - lasting esthetics and little preparation of the underlying dental structure were among main reasons for this decision .
thus , in the presented clinical situation , the dental preparation was restricted to the enamel . besides the optical characteristic similar to the dental structure , glass - ceramic materials have good bonding characteristics to the dental structure .
this increased retention is mainly related to the use hydrofluoric acid to etch their internal surfaces , associated with the use of silane - coupling agents . moreover , when the dental preparation is restricted to the enamel , improved and more reliable bonding may be obtained . in the present case report , the dental bleaching was conducted at the same appointment of the dental preparation .
this procedure , however , could be considered controversial due to the fact that bleaching may influence the extent of dental preparation .
the decision of bleaching at the same clinical was based on the idea that ultrathin veneers were planned from the beginning .
dental bleaching may be considered a safe treatment and may be associated with other therapies as demonstrated in the present case .
since practically no dental preparation was conducted , the patient reported no post - treatment pain .
it is important to note that the color selection should be delayed , as bleached teeth usually appear whiter and chalky immediately after bleaching .
the try - in paste was used to select the cement color only after the application of the silane - coupling agent .
the try - in paste was removed by rinsing with water spray , followed by air - drying .
this protocol of using and rinsing the try - in paste after the application of the silane coupling agent has been proposed to improve the bond strength of the resin - based cement to the ceramics . while rinsing , the excess of unreacted silane was removed .
this excess has been reported to be washable with water at room temperature , and , if not removed , could compromise the coupling of the luting material to the ceramic by hydrolysis .
the inner layer attached to the glass - ceramic is considered hydrolytically stable due to its covalent links to the silica and is not removable by the rinsing procedure .
this type of cement is an appropriate choice for luting indirect veneers in terms of bond strength and increased working time .
the use of light - cured materials for the cementation of veneers , however , is based on the idea that the light could easily pass through the indirect restoration due its translucency and reduced thickness . a concern related to light transmittance through ceramic materials and its influence on cement degree of conversion and
it should be noted that even when dual - cured resin cements are employed , the light activation plays an important role on material 's degree of conversion .
another aspect to be considered when cementing veneers with materials that relies on the ability of light transmission through the ceramics is that not all light - curing devices are equal and that different curing properties may be achieved for the same curing unit if used with a fiber optic or a polymer light guide tip .
for this reason , light - cured resin cements should be light activated carefully , both at cervical , medium and incisal areas of the veneer .
the ultimate success of esthetic treatments is only achieved when the patient is educated and motivated to maintain good oral health .
the patient contribution and periodic control by the dentist is imperative to the long - term success of the treatment .
the minimum thickness anterior ceramic laminate veneers may be a conservative and esthetic alternative to reestablish the form , shape , and color of anterior teeth .
 the aim of this article is to describe the possibility of improving dental esthetics with low - thickness glass ceramics without major tooth preparation for patients with small to moderate anterior dental wear and little discoloration . for this purpose , a carefully defined treatment planning and a good communication between the clinician and the dental technician helped to maximize enamel preservation , and offered a good treatment option . 
 moreover , besides restoring esthetics , the restorative treatment also improved the function of the anterior guidance . 
 it can be concluded that the conservative use of minimum thickness ceramic laminate veneers may provide satisfactory esthetic outcomes while preserving the dental structure . 
INTRODUCTION
CASE REPORT
DISCUSSION
CONCLUSION