Dental Crown is a tooth-like covering placed over a carefully prepared existing tooth. Used to strengthen, restore or improve the appearance of your natural tooth a crown is placed on an individual tooth much like a thimble over your finger. One of the most common is to support the tooth when there is no longer sufficient tooth structure left to place a filling. There are several ways of restoring teeth, the most common being a filling or bonding. Crowns are used to strengthen a tooth and repair badly decayed, broken, severely discolored, misaligned teeth or capped the tooth after root canal treatment. Crowns may also be used to protect the structure of a tooth that is fractured or broken. Crowns completely cover teeth, restoring them to their natural color, size, shape, and function. The location of the crown in the mouth usually dictates the type of material used. The tooth under the crown is reduced in size. The crown will be permanently cemented over the reduced tooth. While you are waiting for the permanent crown to be fabricated, your dentist will provide you with a temporary one to wear. Crowns have a much longer life span than bonding, resist stains better, hold their color and resist chipping and cracking. Crowns, however, take longer to prepare than bonding and are not reversible. Your dentist can recommend which type of restoration is best for your particular situation. If the tooth is severely decayed, little tooth structure remains or after root canal treatment for the back tooth, it may be necessary to place a metal post into the tooth to support the crown. If this is the case, root canal therapy will be performed.
Traditional methods to replace a missing tooth or teeth include the fabrication of a bridge. To replace a missing tooth with a bridge, at least one tooth on either side of the space created by the missing tooth must be prepared for a crown. Then a false tooth is joined to the crowns, and the entire structure is cemented to the prepared teeth. The patient cannot remove the bridge, and special aids are available to keep it clean.
Porcelain fused to metal crown and bridgework
Porcelain fused to metal is mainly comprise of porcelain and metal alloy basis. The combination of porcelain bonded to a supporting structure of metal creates a stronger restoration than porcelain used alone. The metal provides strength to crown and bridge while porcelain replace natural teeth enamel appearance. Dental crown and bridge restorations are traditionally used for 40-50 years. It is successfully proved to be very strong and durable.
All Porcelain (Porcelain structure) crown and bridgework
Because porcelain fused to Metal has disadvantages for biocompatible, some patients show allergic sensitivity after use crowns and bridges 1-2 years because of some particular alloys used in crown and bridge. So, full-porcelain (metal free) play key roles in this kinds of patients. Full porcelain restoration is made of dental materials include porcelain, ceramic or glasslike fillings and crowns. They are also used as inlay/onlay, crowns and veneers. Full-porcelain restorations are particularly desirable because their color and translucency similar to natural teeth. The disadvantage of full porcelain over porcelain fused to metal is resistant to fracture when placed under tension or on impact. The strength of this type of restoration depends on an adequate thickness of porcelain and the ability to be bonded to the underlying tooth. They are highly resistant to wear but the porcelain can quickly wear opposing teeth if the porcelain surface becomes rough.
Zirconia crown and bridgework
Zirconia is widely used in space industry from space suit aircraft parts because of its durable and erosion resistant. Zirconia is the same component of jewelry sub-structure and more suitable for posterior teeth where require greater loading chewing forces. This is latest ceramic technology and the most strength materials in Dentistry market at the moment.