Tuesday, May 5, 2020

Veneer free essay sample

Direct and indirect veneers Dental veneers (sometimes called porcelain veneers or dental porcelain laminates) are wafer-thin, custom-made shells of tooth-colored materials designed to cover the front surface of teeth to improve your appearance. These shells are bonded to the front of the teeth changing their color, shape, size, or length. There are two main types of material used to fabricate a veneer,  composite (resin) and dental porcelain. Porcelain veneers resist stains better than resin veneers and better mimic the light reflecting properties of natural teeth. Resin veneers are thinner and require removal of In 1930, a Californian dentist called Charles Pincus created the first veneers. These were predominantly used to improve the look and smiles of Hollywood actors and actresses at the time, many of whom it is thought, failed to take care of their teeth and appeared glamorous until the moment when they opened their mouth, only to reveal their broken or decaying teeth. It is thought that it was the procedure of adding veneers which led to the legendary ‘Hollywood Smile’. Charles Pincus pioneered dental veneers by gluing a very thin tooth like piece of porcelain over the actors natural teeth to improve the appearance and so create an illusion of perfect straight white healthy teeth, like modern porcelain veneers. The dental veneers only lasted a short while though, as they were glued on with denture adhesive. It was not until 1982, when a research by Simonsen and Calamia took place which showed that porcelain veneers could be etched with hydrofluoric acid which it was felt would enable the placement of veneers to be bonded onto the tooth permanently. Indications Traumatized/fractured teeth Anatomically malformed teeth Hypoplasia of enamel Stained/discolored teeth (intrinsic or extrinsic) Diastemas Misaligned teeth (not too much) Eroded teeth Or just for a better esthetic look on the patients request Contraindications Patients with bruxism Teeth with large class 3 restorations Severely rotated teeth(teeth that are too much rotated) Mandibular teeth Bulimic/Anorectic patients Too little enamel for bonding Patients with a bad oral hygiene Patients with a lot of caries The veneers are divided into three groups according to the materials and techniques that are applied: Direct, indirect and direct-indirect veneers. The direct veneers are made of composite, directly in the dental cabinet of the clinician himself, hence the name â€Å"direct composite veneers†, meaning that the patient will leave the cabinet with the veneers already after the first meeting because no lab work of a technician is needed. It is less expensive than the ceramic veneers, but also less resistant to damage. The indirect veneers on the other hand are made in the laboratory by a technician, and are usually made in ceramics, which implies that the patient will leave the cabinet after the first meeting without the final veneers, but with temporary composite veneers, and a second meeting is required for the cementation of the final ceramic veneers. This choice is of course more expensive for the patient not only because of the ceramics, but also cause of the work that the technician is doing. There is also a small group of veneers called direct-indirect veneers, which is said to utilize the advantages of both the direct and indirect techniques of the restorations with improved physical properties, this is the least used technique that is least used. First meeting: Preparation of the teeth, impression, color One of the fundamental advantages of using porcelain veneers to create changes for teeth, as opposed to other types of porcelain dental restorations, is that very little tooth reduction is needed. In general (and depending upon the specifics of the case) the dentist only needs to trim the ooth the same amount as the thickness of the veneer being placed. In most cases this means that the tooth reduction will be as little as . 4 to . 8 of a millimeter (0. 3-0. 4 at the cervical third and 0. 5 – 0. 8 at the middle and incisal thirds). Thats on the same order of thickness as the plastic credit card carried in a persons wallet. In comparison dental crowns require up to 2 millimeters of trimming, and this amount of reduction is needed on all aspects of the tooth, not just the front side as is the case with porcelain veneers. There can be differing circumstances or philosophies regarding the need to trim the biting edge of a tooth when it is prepared for a porcelain veneer. In some cases the veneer might feather out and end right at the tip of the tooth whereas in other cases the veneer will need to wrap over and encase the biting edge. When the biting edge of the tooth is reduced it is usually on the order of about 1. 5 millimeters. The gingival preparation was in older times almost always places subgingivally, but nowadays they are often placed just supragingival. When the tooth/teeth are prepared for the veneers it is time to take the impression of the dental arches to send it to the dental laboratory where the technician will start making the ceramic veneers. Because it will take some time for the dental laboratory to be finished with the veneers, it is needed for the clinician to create a temporary veneer for the patient, this is easily done with some fluid composite and an amalgam impression of the prepared teeth. The reason for putting temporary veneers is not only cause of the patient’s convenience, but also to protect the prepared surfaces on the teeth from getting destroyed while waiting for the final cementation of the ceramic veneer. The wanted color of the veneer is very important, in an esthetic point of view. The color should be decided in the beginning of the appointment, and under good lighting conditions, the color chosen could be a decision made of both the dentist and the patient, together. Second meeting: â€Å"Try-in† of the veneer, bonding of the veneer When the technician is finished with the veneers he sends them back to the dentist, and then it’s time for the patient’s second visit, in which he will get his temporary veneers replaced by the permanent ceramic veneers. The first thing the dentist is doing is to anesthetize those teeth on which the veneers will be applied, and this is because the cementation of the veneers might be a quite sensitive and sometimes even painful activity. After that the dentist will remove the temporary veneer and then clean the surface of the prepared teeth. To get a strong and long lasting bond between the porcelain and the tooth all debris and temporary cementation material have to be removed. Then the dentist will evaluate the fit, shape and contour of the veneers, and make sure that the veneers fit on the prepared teeth and with the neighboring teeth and structures. At last, the dentist will verify the color of the veneers, and because the porcelain veneers are quite translucent the final color of the veneer will also be dependent on the shade of the cement that will bond the veneer to the tooth. So a number or different test pastes will be tried with the veneers, to see which one that gives the best esthetic appearance of the veneer in relation to the neighboring teeth. Now it’s time for the veneers to be permanently bonded to the prepared teeth, and a few different procedures are made to optimize the bonding of the veneers to the dental substances. First the veneer itself has to be cleaned and prepared for the bonding, and this is done through surface etching for 90 seconds and then rinsing and drying for another 60 seconds, after that the dentist applies a silane that needs to be dried for one minute in about 100 degrees Celsius, and the veneer is now ready to be bonded to the tooth. After that the dentist will start etching the surface of the prepared teeth, for about 20 seconds, and then wash and dry the tooth so all traces of the etching gel is removed. Then the bonding agent it applied on the prepared teeth and light cured for about 20 seconds. The dentist will now put the cement inside the veneer and place the veneer onto the prepared tooth and then gently press on the veneer so that excess cement will come out from underneath the veneer. The dentist removes all the excess cement from around the veneer and tooth and will then light cure the cement for about 1 minute. Now the veneer is put there for good and will hopefully stay there for at least 10-15 years. The dentist will finish the work by emoving the now hard excess of cement around the veneer and also fix the shape or outline of the veneer if there are any issues with those. And the last thing to check is the mandibular movements while having an occlusion paper in between the veneer and the antagonist to check so that the veneer is not too long, but if so, then to slightly use the drill to adjust the veneer to a better occlusal fit. Summary Porcelain veneer restorations requ ire close attention to detail from beginning to end. It is often important to go slowly when working with these cases. Patients receiving them have high expectations that go beyond considerations of function alone. But also a good oral hygiene of the patient is necessary in order to maximize the lifespan of the veneers, which is around 10-15 years. Success is the result of careful selection of teeth to receive veneers; preparing teeth in a manner that optimizes the aesthetic potential of the veneer; employing techniques that maximize the strength of both the veneer and its adhesive bond to the tooth; utilizing high-quality provisional veneers; insisting on a precision fit; and paying attention to the details of adhesive bonding protocols.

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