Prosthodontics

In dentistry, the crown of a tooth is the upper, visible portion of the tooth. It may refer to the natural tooth structure or to the prosthesis which caps and completely covers a tooth. A synthetic dental crown can add structural, functional, and aesthetic value.

Synthetic dental crowns are used for many reasons, such as the following:

• To cover and hold together a weak tooth. A crown can protect a weak tooth, whether weakened from decay or breakage or wear, from future breakage.
• To replace a large filling which, when removed, leaves a tooth without sufficient structural stability.
• To restore a broken tooth by providing strength and support to the remaining tooth.
• To cover and protect the remaining tooth structure after root canal treatment. The crown also aids in preventing bacteria from reentering and re-infecting the tooth.
• To cover a dental implant. A dental implant is designed to hold a dental prosthesis, such as a crown.  
• To anchor a dental bridge. Crowns are installed on abutment teeth when a fixed bridge is used.
• To cover a badly discolored or misshapen tooth for better aesthetics.

To create and install a dental crown, impressions of the prepared tooth must be taken. The impressions are then used in a lab to fabricate the final crown which will be cemented into place during a separate appointment. Crowns may be made out of resin, ceramic, metal, porcelain fused to metal, and porcelain fused to zirconia. Each material had benefits and disadvantages when it comes to price, aesthetics, and durability, which can be discussed with your dentist to determine which works the best in your circumstances.

The maintenance of a crown includes proper tooth brushing and flossing and regular dental cleanings, just as your natural teeth require. With proper care, crowns may last 5-15 years, or even a lifetime. A crown needs maintenance to ensure the health of the tooth it covers. If a crown comes loose or breaks or leaks, see your dentist immediately to tend to the health of the tooth underneath.

Also known as fixed partial dentures, dental bridges are functional and aesthetic solutions to missing teeth.

Bridges are comprised of pontics (artificial teeth) and an anchoring system. The use of bridges requires remaining teeth around the gap to be prepared as abutments onto which the bridge will be anchored. Bridges come in three main forms which are differentiated by the ways in which they are anchored.

• In a traditional bridge, the artificial replacement teeth are anchored by crowns fixed to the abutment teeth on both sides of the gap. This is the most common type of bridge used, favored for its stability.
• A cantilever bridge is used when there are supporting teeth on only one side of the missing teeth. Again, the abutment teeth are prepared for crowns.
• The Maryland bonded bridge, also called a resin-bonded bridge, uses a more conservative anchoring system, requiring less preparation for the abutment teeth. In this type of bridge, the pontics appear to have “wings” that are bonded to the abutment teeth with resin cement. This style bridge is most often used in front tooth restorations and in younger patients.

The materials used for the fabrication of bridges are metal, resin, and porcelain, the choice of which factors in the price and aesthetics of the finished bridge.

Taking care of a bridge is the same as taking care of natural teeth, requiring regular brushing, flossing, and dental visits. With proper care, a bridge can last many years.

If you are interested in a bridge, you should discuss with your dentist the treatment plan that would work best for your teeth.

Removable dentures come in two forms – complete removable dentures to replace a full arch of teeth and partial removable dentures when some natural teeth remain.

Removable dentures are generally made with lightweight materials for comfort and ease of use. The artificial teeth in removable dentures are generally made of acrylic resin, although porcelain is sometimes used for more natural front teeth. However, porcelain is usually used sparingly in removable dentures to minimize weight. The base material of removable dentures mimics the gums and other soft tissue. The materials available for the base material for complete removable dentures are as follows:

• Standard: The material that has long been trusted as the base material for dentures is a mixture of plastic (acrylic resin) with metal for stability.
• Valplast® Combination: This material is a flexible nylon resin growing in popularity for use in removable dentures. When used for the fabrication of complete dentures, metal is also incorporated for added stability.
• Ivocap: This is an acrylic resin that is fabricated under high pressure for maximum strength and durability.

The materials available for the base of partial removable dentures are as follows:

• Standard: As with complete removable dentures, the standard material for partials is an acrylic resin with metal for stability and support.
• Valplast®: This flexible nylon resin is used in particular for partial dentures, offering a material option that does not utilize metal as support.
• Valplast® Combination: This option benefits from the stability and support offered by metal and the comfort of the flexible Valplast® nylon resin.

If you decide to get removable dentures, impressions will be taken of your remaining teeth, gums, and surrounding bone. These impressions will be used to design and construct your new dentures.

When you receive your removable dentures, you may experience some discomfort, additional salivation, and what seems to be an improper fit. Let your dentist know if and where you feel discomfort, but this is all normal as your mouth adjusts to the new dentures and usually goes away in the first week after receiving your new dentures.