veneer preparation

 the Veneer step by step

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2. 2. Definition A dental veneer is a thin layer of composite material or dental porcelain bonded to the surface of a tooth 
3. 3. Indication • Improve extreme discolorations such as tetracycline  staining, flourosis, devitalized teeth, and teeth darkened from age. • Repair chipped or fractured teeth.  • Closing of diastemas between teeth.  • Ability to lengthen anterior teeth.  • Improve the appearance of rotated or misaligned teeth 
4. 4. Contraindication • If little or no enamel is present, full crown should be considered.  • Certain tooth-to-tooth habits like bruxing or  clenching, or other para-functional habits such as pencil chewing or ice crushing. • Teeth that exhibit severe crowding.  • Certain types of occlusal problems such as Class III & end-to-end bites. 
5. 5. There are three types of veneers (1) Conventional Porcelain Veneers. (2) Lumineers.  (3) Composite Resin Veneers.  
6. 6. (1) Conventional Porcelain Veneers. A conventional porcelain veneer is a thin piece of porcelain that is bonded to the front of a tooth. Porcelain is a durable, translucent, strong, naturallooking, and beautiful material. In most cases, Conventional Porcelain Veneers will create the most beautiful results, and are thus the most common type of veneer used. 
7. 7. It is done either in one appointment by using the prefabricated porcelain(ready made) veneer or in two appointments by using porcelain veneer fabricated in the lab.
8. 8. First Appointment (VENEER PREPARATION PROCEDURE)  Tooth preparation We have four aspects of tooth preparation 1-Labial reduction 2-Interproximal reduction 3-Incisal modification 4-Cervical definition
9. 9. -Place a horizontal facial depth cut, it is usually 0,3 mm from proximal line angle to proximal line angle. Make this depth cut at the junction of the cervical and middle one-third of the facial surface of the tooth.* -Paralleling the entire gingival margin, prepare a definitive chamfer finish line. -Continue the definitive chamfer finish line with diamond bur from the papilla tip toward the incisal edge on both the mesial and distal proximal surfaces.
10. 10. -The facial depth cuts are removed with the diamond bur, and the long axis of the diamond bur is “rolled” into the proximal chamfer area to eliminate any sharp line angles. Good prep Bad prep
11. 11. How to handle incisal edge ? Path of Insertion Restricted Unrestricted Most common Less common
12. 12. -There are three ways to manage incisal edge coverage. no incisal edge coverage- easiest to manage, requires provisionalization less because there is less dramatic change in appearance. cover incisal edge – less stress on internal aspect of veneer if rounded, less chance of die abrasion, I use on centrals and laterals most for unworn teeth wrap around incisal edge- this technique used more when significant wear already exists and B-L width is thick. Also provides some mechanical retention for longer extensions (>1.5mm)
13. 13. Impression The retraction cord should be left in place if possible during the impression.. It is best to use a polysiloxane or polyether material for the impression since multiple pours are often needed for the laboratory procedures. Placing soft wax in the lingual embrasures prior to taking the impression will minimize tearing of the impression in these areas Temporary Veneers If they are necessary or desired, they are hand sculptured using composite, kept supragingival, out of heavy occlusion, and attached by spot etching the enamel in the center of the tooth away from any margins. Other methods can be used which include acrylic type indirect methods.
14. 14. Shade selection Clean teeth with pumice and water to remove any extrinsic stains which exist
15. 15. Between appointments The laboratory procedures 
16. 16. Second Appointment (VENEER CEMENTATION PROCEDURE) Remove temporary  Clinical try-in. Evaluate fit and esthetics All veneers should be placed without bonding medium on teeth to assess the fit.
17. 17. Preparing the restoration for cementation. -Clean the restorations with acetone or Cavilax if you  have tried it in with resin based systems. If you have used only water soluble medium (glycerin, K-Y jelly, Try-in pastes) you need only to rinse. It is a good idea to clean with enamel etchant (35% phosphoric acid) to help clean any salivary contaminants that may have come in contact with the bonding surface. -Etch. etch with porcelain etchant (porcelain conditioners- 10% HF acid). The time of etch depends on the ceramic materials used. (Porcelain > 3min Empress < 1 min).
18. 18. -Apply Porcelain Primer or Silane Coupling  Agent. use a prehydrolized silane which means you do not have to mix two components (usually contained in cementation kit (Nexus, Kerr) It is applied with a brush. The coupling agent acts to wet the surface of the porcelain. The silane coupling agent is allowed to set on the surface (usually for at least 60 sec but some are shorter periods). It can be dried with a gentle stream of air. Do Not Rinse. Set prepared veneer in a lightproof box until ready for cementation
19. 19. Prepare tooth for bonding. Isolation. Rubber damn isolation is usually not  practical for multiple anterior cementation techniques. Cotton roll isolation and an assistant are usually sufficient for cementation. Clean all tooth surfaces with rubber cup and pumice/water mixture or chlorhexidine soap/pumice mixture and rinse thoroughly. Place clear Mylar strip between involved adjacent teeth to minimize etching and placement of adhesive and cement on the adjacent unbonded teeth . Do two veneers at a time. The sequence I usually use is: both centrals first, then lateral and cuspid on one side and finally the lateral and cuspid on the opposite side.
20. 20. Etch the preparation. The enamel is etched for 15-30 seconds with 35% phosphoric acid. Gel etches are easier to control. Rinse the tooth thoroughly to make sure no etchant remains and air dry with air syringe or high evacuation. Adhesive is applied to the surfaces of the preparation. In the Nexus system this layer is air thinned and cured prior to cementation. In other systems this layer may be left to cure during the cementation.
21. 21. Apply the cement (Nexus, Kerr) to the  preparation and the surface of the veneer with a brush or plastic instrument. Light cured materials are used for cementation since the veneers are extremely thin and transmit enough light. Most cementation kits now contain two viscosities of cement. Seat the restoration with firm finger pressure and hold in place while the excess cement is removed with a sable brush Light cure veneer from the facial surface for at least 60 seconds. You cannot overcure these restorations. Cure from lingual surface if the incisal edge is included in the restoration.
22. 22. Finishing and polishing procedures. Remove excess set bonding material with sharp carvers. Keep instruments stable against restoration and tooth surface to minimize soft tissue damage. Recontouring and occlusal adjustments of the porcelain are done with a fine diamond and high speed using water coolant. Any surface which has been modified with a finishing diamond needs to be polished. If no marginal discrepancies were present between the tooth and ceramic, finishing can be initiated with finishing carbides, discs and rubber points 
23. 23. (2) Lumineer What is the difference between Lumineers and standard porcelain veneers? The main difference is that Lumineers are made from a  special patented cerinate porcelain that is very strong but much thinner than traditional laboratory-fabricated veneers. Their thickness is comparable to contact lenses. 
24. 24. Advantages • Lumineers can be placed on the teeth without removal  of the tooth structure. • Patients can receive their veneers quickly, usually within two weeks from the date that the impressions are made. • Lumineers bond directly to the tooth, making the bond very strong. They are also very long-lasting- up to twenty years or longer. • Lumineers are a reversible procedure.
25. 25. Although Lumineers are the most advantageous  option, there are certain limitations to be considered: • Lumineers can only be placed on teeth that are in good structural condition. The teeth must be free of decay. Any existing fillings must also be in good condition, along with the surrounding gum in the area where the Lumineers will be placed.. • The patient must have good oral hygiene, with no receding gums or signs of gum disease. Bleeding of the gums will interfere with the bonding process. • Because there is very little or no tooth preparation, a small bump is likely to develop between the veneers and the gum.. The bump may create an irritation to the gum, and may increase the chances for staining and tooth decay.
26. 26. The LUMINEERS No-Prep Technique allows LUMINEERS to be placed over the existing teeth without the removal of any form of tooth structure. Therefore, anesthesia and temporaries are also not required. The LUMINEERS Minimal Contouring Technique requires slight modification of the enamel but never touches dentin during LUMINEERS placement. Only .3 mm-.5 mm enamel is removed, causing no sensitivity for the patient and therefore no need for any anesthesia.
27. 27. PREPARATION OF LUMINEERS 1. Polishing Clean the teeth with Porcelain Laminate Polishing Paste and rinse. 2. Refresh the Enamel Perform minimal enameloplasty with a prep diamond bur, using light pressure. –Use the whole length of the bur, keeping contact with the teeth.
28. 28. 3. Interdental Strips Isolate the teeth receiving LUMINEERS from the teeth not receiving LUMINEERS by applying Paint-On Dental Dam or placing metal interdental strips in order to prevent etchant from contacting adjacent teeth. 4. Etching 1. Etch the teeth with Etch ‘N’ Seal® for 20 seconds. 2. Rinse thoroughly with water, then dry.
29. 29. 5. Bonding Application 1. Add 5 coats of Tenure® A+B. 2. Add 1 coat of Tenure S to the teeth. Note: Tooth surfaces must be shiny.
30. 30. 6. Prime-Bonding on LUMINEERS 1. Add 1 coat of Tenure A+B on the inner side of the LUMINEERS. 2. Add 1 coat of Tenure S on the inner side of the LUMINEERS. 7. Ultra-Bond® Plus on LUMINEERS Add an even layer of Ultra-Bond® Plus resin cement to the inner side of the LUMINEERS. Work upwards from incisal edge of the LUMINEERS to gingival edge and keep light contact with the LUMINEERS
31. 31. 8. Insert the LUMITray 1. Remove the Paint-On Dental Dam or interdental strips. 2. Center the LUMITray (midline). 3. Insert the tray in one smooth movement. Apply light and continuous buccal pressure. Take your time for the placement. 4. Remove excess Ultra-Bond Plus resin cement from the gingiva with a microbrush.
32. 32. 9. Cure LUMINEERS Through LUMITray 1. Tack-cure each tooth using a sweeping movement.Set Light for 3 seconds. 2. Remove more excess cement with a probe. 3. Light-cure each tooth for 3 seconds through the tray.
33. 33. 10. Clean-Up and Open Interdental Spaces 1. Remove Ultra-Bond Plus cement from interproximal spaces.Maintain complete control over the instrument. If difficult, postpone to follow-up visit. 2. Remove excess cement using the finishing bur kit.
34. 34. 11. Light-Cure the LUMINEERS Light-cure each LUMINEERS individually for a second time, on both the lingual and buccal sides, for 5 seconds with Sapphire Light. 12. Check Occlusion and Polish 1. Check and finish the occlusion. 2. Polish the LUMINEERS with Porcelain Laminate Polishing Paste.