Post on 12-Jun-2015
“laminate veneer,,
A veneer is a thin layer of restorative material placed over a tooth surface, either to improve the aesthetics of a tooth, or to protect a damaged tooth surface .
It has a translucent quality which means that they give a natural looking tooth ,
and it's three types (porcelain,Acrylic and composit )
Definition:
-Veneers were invented by a California dentist named Charles Pincus in 1928 to be used for a film shoot for temporarily changing the appearance of actors' teeth .
-Later, in 1937 he fabricated acrylic veneers to be retained by denture adhesive, which were only cemented temporarily because there was very little adhesion .
.
History:
-The introduction of etching in 1959 by Buonocore aimed to follow a line of investigation of bonding porcelain veneers to etched
enamel .
-Research in 1982 by Simonsen and Calamia , revealed that porcelain could be etched with hydrofluoric acid, and bond strengths could be achieved between composite resins and porcelain that were predicted to be able to hold porcelain veneers on to the surface of a tooth permanently
Indication: 1- Fractured tooth
2 -Intrinsic staining
3- In case of multiple teeth
to create a
"Hollywood“ type of
makeover
4- Small teeth.
5- Malposition teeth
6- In case of worn away the edges of the teeth 7- Lengthen teeth that have been shortened by wear, 8- Fill the black triangles between teeth .9- Provide a uniform color, shape, and symmetry, and make the teeth appear straight. 10- Strengthen worn teeth.11- For aging patients with worn dentition.
12- Enamel hypoplasia 13- Closure of diastemas 14- Root exposure 15- Abrasion and erosion 16- Large pulp size17- Anatomical maleform teeth18- Tooth wear
Contraindication: 1-High caries index .
2 -Poor plaque control. 3-Extensive existing
restoration. 4-BruxximS.
5-Posterior teeth . 6-Edge to edge or cross bite.
7 -Short teeth. 8 -In case of orthodontics.
9-Simulated straightening of
the teeth
for younger people with
healthy teeth
10 -Crowding of misaligmed
teeth with inadquate
enamel present
11 -Patient with habitual
clenching and grinding
12-Preiodantal disease
1 .Esthetic.
2 .Stain resistant and
Stronge .
3 .The color of a laminate
veneer can be selected such
that it makes dark teeth
appear whiter.
4.Veneers is more
conservative.
Advantage:
5 . Minimal tooth preparation required .
6 .Color stability.
7-Resist abrasion.
8-Well tolerated by gingiva .
1.Expensive.
2.Requires laboratory
procedures .
3 .Porcelain enamel margins
may be thin and difficult to
finish.
4 .Brittle .
5 .Pitting by acidulated
fluoride treatment.
Disadvantage :
7 .Can sometimes be
difficult to temporize.
8 .Color cannot be
altered substantially
after
placement.
9 .Placement is difficult
and time-consuming .
10.Potential for over-
contouring.
11 .Cannot be repaired
easily.
- A full set of radiographs is obtained. Panoramic, bite wing, complete diagnostic evaluation of the periodontal status for each individual tooth. -Full upper and lower impressions and a bite record are obtained so the laboratory can pour study models and mount them in a centric relation position on a semi adjustable articulator.
Preoprative procedure:
1-Shade guide under good illumination of normal white day light and operatory light
after wetting the buttons . 2-Wet condition before
isolation . 3-The three components of
color are :-Hue: the color itself .
-Chroma: saturation or intensity .
-Value: also called luminosity or brightness, is the most influential component .
*A graduation of color usually occurs from gingival to incisal with the gingival region being darker.
Shade selection :
Tooth preparation:
• Lengthening the tooth requires special attention
during the preparation stage.• The occlusion , especially
the anterior guidance, should be very carefully evaluated.
• Palatally finishing preparation lines can be applied and in doing so , the facial-palatal thickness of the incisors should be taken into consideration.
Keep in mind…
-When to do preparation minimal and limited to enamel of tooth.-The enamel should be reduced by 0.3-0.5 mm in a conservative intraenamel preparation.-The finish line should be as close to the gingiva as possible , or slightly sub-givgival.- However, no matter what the condition is, cervical preparation is essential to display the laminate's normal emergence andto prevent overcontourin
Enamel has different thicknesses at the gingival, middle and incisal 1/3rds of the facial surface of the tooth, so thereTwo different-sized depth cutters (Komet #868A.314.018 and # 868A.314.021) control the depth of the facial tooth preparation.
Preparing Facial or labial the 1/3rd
..
-Three-wheel diamond depth cutter , creats the depth-orientation groove (0.3) mm in G half of the L.S.
-Three-wheel diamond bur (0.5)mm reduction in incisal
-Remove tooth structure remaining B/t the grooves with a round ended tapered fissure diamond bur.
-G portion of the facial reduction while the tip of chamfer finish line ,
Preparing the Incisal and lingual1/3rd::
There are two basic techniques for the placementof the incisal finish line;
1)The first terminates the prepared facial surface
at the incisal edge.* There is no incisal reduction or prep of the lingualsurface and it can be in the form of a window orintra-enamel preparation or the feathered incisalpreparation.
(2) In the second technique, the incisal edge is slightly reduced and the porcelain overlaps the incisal edge, terminating on the lingual surface.
* In a retrospective clinical evaluation the two techniques were used equally and both provided clinically acceptable results.
:Interproximal Preparation
-Reduction the proximal by using the round-end. - open the contacts area without breaking.- To correct an uneven finish line,ensure that the diamond is parallel with the longaxis of the tooth and parallel to the mid-line. Even though this seems to be a minor detail, it is a vitally important one.
-Examination of the
prepared teeth is
necessary .
- The dentist must be careful
to remove any sharp angles.
-Smooth margins that are
fully exposed and readily
cleansabls
Finishing the Preparation:
impression:-The retraction cord should be
left in place if possible during the impression. -Use a polysiloxane or polyether material for the impression - Or we can use A polyvinyl siloxane impression material to take a full arch impression.
- A light body material is injected around the margins as the impression tray was loaded with a heavy body material.
-The tray is seated and the material was allowed to set completely before it’s removed from the patient’s mouth-The opposing arch impression is also taken in a polyvinyl material -A hard-setting occlusal registration was taken bite registration after removal from the patient’s mouth.
The veneers should first be tried-in before they arebonded to eliminate unexpected surprises.When the patient arrives for the final appointment.
what to do :
- First anesthetized for the comfort of the patient._ Clean with flouride free pumice_ Fried in individually with glycerin_Remove the excess_Checked for fit and shade if satisfactory
Try-in:
Cementation :
-Frist do good isolation. -Sparated with soft matrix strip.-Etche 15 to 30 sec with 37% phosphoric acid. -Applied Boinding agent. -Put thin lyer of luting agent. -Apply veneer slightly without force. -Excess cement is removed. -Partial curing for 5 to 10 sce.-Aemove of all excess. -Veneer should be cured from all directions for at least 40sce per surface.
Maintaining your veneer :1.Initial follow-up :
-Scheduled one week post-cementation to evaluate tissue response and margins,
-At 3-4 month intervals.2.Clean it by brush and floss
every day for good oral hygiene.
3.Avoid using vertical strokes during scaling ,
4.Avoid the use of acidulated fluoride.
Bonding of
laminate veneer:
Bonding to enamel:
Enamel bonding is mainly a
micromechanical
interlocking of resin with the
enamel surface
so we etched enamel with
37% phosphoric acid and
rinsed and dried priorto the
application of the resin.
Ceramics Bonding is micromechanical bondAnd it etched with hydrofluoric acid.
Dentin bonding is a
micromechanical bond
but it is more complex
and difficult and
Hydrophilic resins must
be used .
Bonding to ceramics:
Bonding to dentin
(1) Planning the case,(2) Conservative (enamel saving) preparation of teeth,(3) Proper selection of ceramics touse,(4) Proper selection of the materials and methods of cementation of these restorations,(5) Proper finishing and polishing of the restorations,(6) Proper planning for the continuing maintenance of these restorations(7) Proper shade selection .
for success the laminate veneer we should give a great attention of :
1-Marginal discoloration and
loss of color stability
2-Breakdown in the bond
3-Cohesive failure and repair
4-Improper occlusion and its
periodontal implication
5- Improper anatomical form of
the veneer
6- Gingival recession
Failure of laminate veener :
Cases...
(1,,,)
(2,,,)
(3,,,)
(4,,,)
Referance
1-http://www.ncbi.nlm.nih.gov/pubmed
2-http://
www.slideshare.net/aneeqa_yaqub/dental-veneers?fro
m_search=7
3-CONTEMPORARY ESTHETIC DENTISTRY
4-Science and Art of Porcelain Laminate Veneers
Done by: Lubna Al-Tareb
Keffaya Al-shareffNoha Al-zomaniShrooqe Al-taibi
Thank you