Veneer (dentistry)

Overview
In dentistry, 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. There are two types of material used in a veneer, composite and porcelain. A composite veneer may be directly placed (built-up in the mouth), or indirectly fabricated by a dental technician in a dental laboratory, and later bonded to the tooth, typically using a resin cement such as Panavia. In contrast, a porcelain veneer may only be indirectly fabricated.

History
Veneers were invented in the 1930s by a California dentist named Charles Pincus. At the time, they fell off in a very short time as they were held on by denture adhesive. They were, however,useful for temporarily changing the appearance of movie actors'/actress's teeth.

Research started 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. This was confirmed by Calamia in an article describing a technique for fabrication, and placement of Etched Bonded Porcelain Veneers using a refractory model technique and Horn describing a platinum foil technique for veneer fabrication. Additional articles have proven the long term reliability of this technique.

Today, with improved cements and bonding agents, they typically last 10-15 years. But patients who receive veneers should understand that they may only last 10-15 years and then may have to be replaced. This can be very expensive since porcelain veneers cost around $1,000 each in 2006 prices. They are said to be somewhat more durable and less likely to stain than veneers made of composite.

Usage
The advantages of using a veneer to restore a tooth are numerous. Very good aesthetics can be obtained, with minimal tooth preparation (i.e. drilling). Traditionally, a reduction of around 0.5 mm is required for a porcelain veneer. Composite veneers are becoming more popular as they are easy to repair, whereas porcelain veneers have a tendency to fracture. It can be very difficult to match the shade of an individual veneer to the remaining teeth, hence placing several veneers is common.

There are some newer veneers which do not require any drilling in order to remove tooth structure. Instead, these veneers are constructed to be placed on top of teeth. As a result, treatment is less invasive and may be less time-consuming. On the other hand, since the teeth are not reduced in size the veneers may appear too large or bulky unless the material used is extremely thin. Therefore, the success for these veneers is best when limited to specific cases.

Veneers may be used cosmetically to resurface teeth such as to make them appear straighter and possess a more aesthetically pleasing alignment. This may be a quick way to improve the appearance of malposed teeth without need to use orthodontics. However, the amount of malposition of teeth may be such that veneers alone may not be enough to correct the aesthetic imbalance. Instead, orthodontics would need to be used, or orthodontics combined with veneers. The dentist who places veneers must be careful since veneers could increase the thickness of the front face of the teeth. If the teeth are too thick on the face they may appear to stand out and push out the lips. The effect may be enough to give the patient a full or chipmunk appearance when the lips are closed. Veneers must also be created such that the patient bites into them with minimal force. Otherwise, they may chip off. So, patients whose lower jaw protrudes out farther than their upper jaw, otherwise known as a class III bite, may not be good candidates for veneers because the teeth of the lower jaw may bite into the teeth of the upper jaw such as to dislodge the veneers.

case reports
1: use of veneers to close diastema

A patient has approached our clinic for an economical solution for closing the gaps between the front teeth. Patient has been advised Ceramic laminates, surely one of the best solution but unaffordable for patient.Next best solution is composite laminates with or without fiber splinting. Composite laminates/ veneers was choosen because patient wants the teeth to be separated from each other. Probability of reappearance of spaces was explained to patient, if the tongue thrusting habit is not stopped.The final restoration satisfied the patient's expectation of aesthetics. To see the photographs, you can refer to.