CROWN & DENTAL BRIDGE

(Indirect Restorations)

Indirect restorations are fixed prosthesis, which are permanently cemented to existing teeth. They can either cover a single tooth in case of a crown or replace missing teeth with a bridge. Dental crowns, dental bridges and veneers are classified as cosmetic dentistry.

Cosmetic dentistry is the portion that deals with improving appearance, enhancing a smile, through dental procedures.

Dental Crowns

What is a crown?

A dental crown is a type of cap that is placed on a tooth to modify the appearance of the natural tooth or to help protect the remaining structure of a tooth. Dental crowns are also placed on root canal treated teeth to prevent leakage of bacteria into the tooth. The crown creates a tight seal, which prevents microleakage and possible re-infection of the tooth. Dental crowns are also commonly used in full mouth reconstruction to provide the patient with a more natural bite and to replace worn natural crowns. This will allow the patient to chew and function more comfortably.

Natural tooth shade or shape modification can be easily accomplished with a crown because it is fabricated in a dental laboratory under controlled conditions. Dentists are able to correct alignment of a natural tooth and modify the shade to match the rest of the teeth.

Another common reason for crowning a tooth is to protect the weakened, remaining tooth structure and prevent tooth fracture. A tooth can be weakened by a traumatic event or normal wear. There are also other factors, which can weaken a tooth. These include: large cavity, large filling, an opening that was made during root canal treatment, defects within the structure of the tooth, fracture of a tooth.  

Even though a dental crown in most cases does cover the majority of the tooth, good oral hygiene is crucial in its long-term success. Crowned teeth are at even greater risk for getting a cavity. This is due to potentially irregular transition from a natural tooth to the crown margin.

After fabrication, a crown is permanently cemented on to provide ideal esthetics and function

Purpose:

-replace missing tooth structure

-improve esthetic appearance by covering the tooth remains all the way to the gum line

-provide a good seal for a root canal treated tooth

-avoid that sunken-in appearance caused by missing teeth usually present in the older population

-stabilizes that area of the dental arch to give you a more youthful appearance

Crowns are crafted and designed to perfectly fit and blend with your natural teeth.  

    -shade selection allows an ideal esthetic result

    -the shape is matched to surrounding teeth which makes the cemented crown seem as a natural unaffected tooth

Cost of a dental crown:

Dental crown cost can vary greatly across the country. Prices can range from about $500 to as much as $1800. Dental crown prices are higher than cost of a filling for several reasons:

A dental crown is considered a long-term restoration (life span of about 10-20 years. Although the length of time that a crown will last is dependant upon several factors, which include quality and quantity of oral hygiene (how often and how well teeth are brushed and flossed), caries rate (how many and how often cavities form), how precisely the crown fits on the tooth, and the area in the mouth where the crown is fabricated (anterior teeth are usually easier to maintain than back teeth).

Several factors can determine cost. A dental crown fabricated by a general dentist will on average cost less than a crown fabricated by a prosthodontist. The cost of a crown can also depend on which part of the country you live in, on type of materials used, experience of the lab technician who will be fabricating the dental crown and the time spent fabricating it.

Dental insurance can cover the cost of a dental crown. Crowns are classified under major dental work. With most dental insurance plans dental crowns are covered at 50 percent. Although, the coverage can range from 50 to 100 percent. Usually the better dental plans can cover 80 and up to 100 percent of the cost of the crown. You might be required to see a dentist that is a participating provider to obtain better coverage on dental work. Check with your dental insurance company for details.

Flossing around crowns and bridge work is the best method of keeping healthy gums and teeth. Floss disrupts build-up of plaque which contains problem causing bacteria. It is recommended to floss at least once a day.

Shop For Floss

Keeping the area under bridge work as well as under orthodontic wires(braces)clean is also very important. Since it is almost impossible to slide the floss through using superfloss allows for access to hard to clean areas.

Shop For Super Floss

Another great dental aid is the floss threader. It serves the same function as superfloss. You tread the plastic floss holder with floss and use it to transfer floss under bridgework and orthodontic wire.

Shop For Floss Threaders

Different types of dental crowns:

Our teeth are made up of the outer shell of tooth enamel and an inner portion of dentin. Structurally, enamel is very brittle without the support of dentin. As we age our teeth can become weaker due to structural changes. Parafunctional habits such as clenching or grinding of teeth, trauma, and normal and abnormal wear are some of the more common reasons for more compromised teeth. Over time teeth can develop cracks, cavities and normal and abnormal wear which can weaken the overall tooth structure even more. The best way to deal with a compromised, weaken tooth is by covering it with a crown. A dental crown is a restoration which encircles and partially or completely covers the tooth. The crown will keep the tooth structure intact even under great biting forces. Over the years there have been several crown designs and various materials used. For the purpose of our discussion we will focus on three different types of crown designs: metal, all porcelain, and porcelain fused to metal crowns.

All Metal Dental Crowns:

Dental crowns made completely out of metal have been used for decades. They vary from crowns made out of base metal alloy to crowns made out of gold alloy. These crowns are very strong and durable. Base metal crowns are usually the least expensive

crowns available. The fit of these crowns is acceptable. They do tend to corrode over time. Gold crowns are more inert and stable. Gold alloy crowns are softer and provide an excellent fit. These crowns have the best fit out of all different types of crowns. A well fitting gold crown can outlast all other crowns. Another benefit of a gold crown is that it doesnąt cause excessive wear on opposing natural teeth, which is the case with porcelain. The only disadvantage of a gold crown is that it is either yellow or white in color. This makes them less popular than other more aesthetic crowns. They are still commonly done in the back regions of the mouth where they are not as noticeable.

All Porcelain Dental Crowns:

All porcelain dental crowns are tooth colored crowns without any metal substrate. These crowns are highly aesthetic and usually recommended for teeth in anterior regions. Porcelain structure is brittle and prone to fracture which steered practitioners from

placing these crowns in the high stress, posterior regions. However, with the advancements made porcelain materials and crown fabrication techniques these certain porcelain crowns can be confidently used throughout the mouth. The main advantage of an all porcelain crown is superior esthetics. The color and translucency of these crowns can be matched to natural teeth. In addition the crown can be stained to match other natural crowns in the mouth ideally. The disadvantage is that the fit of porcelain crowns, even though is excellent, is not as good as a gold crown. Due to more labor-intensive fabrication techniques the crown costs more to fabricate, which translates to a higher cost of the crown. Even with the use of zirconia, which is a very strong type of porcelain many practitioners prefer not to use all porcelain crowns on the back teeth. Another disadvantage of an all porcelain crown is the preparation of the tooth for a crown. The tooth has to be shaved down much more than if it was prepared for a metal or porcelain with metal crown. Overall, the superior aesthetics that these crowns provide outweigh any of the negatives.

Porcelain Fused to Metal Dental Crowns:

Porcelain fused to metal dental crowns (PFM) are tooth colored crowns with a metal substrate. These crowns are aesthetic and usually recommended for teeth in posterior regions. The porcelain surface provides an aesthetic appearing crown. The metal substructure provides a good marginal fit of a metal crown as well as structural support for the porcelain. These types of crowns work well in high stress areas where aesthetics is not the primary concern.

©Copyright 2005 Virtual Dental Center All Rights Reserved