When a tooth is extensively decayed a filling may not be enough to fix the tooth. It may need an inlay, an onlay or crown to restore it. Both crowns and most bridges are fixed prosthetic devices. Unlike removable devices such as dentures, which you can take out and clean daily, crowns and bridges are cemented onto existing teeth or implants, and can only be removed by a dentist. A crown is used to entirely cover or "cap" a damaged tooth. Besides strengthening a damaged tooth, a crown can be used to improve its appearance, shape or alignment. A crown can also be placed on top of an implant to provide a tooth-like shape and structure for function. Porcelain or ceramic crowns can be matched to the color of your natural teeth. Other materials include gold and metal alloys, acrylic and ceramic. These alloys are generally stronger than porcelain and may be recommended for back teeth. Porcelain bonded to a metal shell is often used because it is both strong and attractive.
Your dentist may recommend a crown to:
A bridge may be recommended if you're missing one or more teeth. Gaps left by missing teeth eventually cause the remaining teeth to rotate or shift into the empty spaces, resulting in a bad bite. The imbalance caused by missing teeth can also lead to gum disease and temporomandibular joint (TMJ) disorders.
Bridges are commonly used to replace one or more missing teeth. They span the space where the teeth are missing. Bridges are cemented to the natural teeth or implants surrounding the empty space. These teeth, called abutments, serve as anchors for the bridge. A replacement tooth, called a pontic, is attached to the crowns that cover the abutments. As with crowns, you have a choice of materials for bridges. Your dentist at MFD can help you decide which to use, based on the location of the missing tooth (or teeth), its function, aesthetic considerations and cost. Porcelain or ceramic bridges can be matched to the color of your natural teeth.
The combination of bacteria and food causes tooth decay. A clear, sticky substance called plaque that contains bacteria is always forming on your teeth and gums. As the bacteria feed on the sugars in the food you eat, they make acids. The acids attack the teeth for 20 minutes or more after eating. Over a period of time, these acids destroy tooth enamel, resulting in tooth decay. Tooth decay is heavily influenced by lifestyle what we eat, how well we take care of our teeth, the presence of fluoride in our water and toothpaste. Heredity also plays a role in how susceptible your teeth may be to decay. Adults are especially at risk for cavities if they suffer from dry mouth, a condition due to a lack of saliva. Dry mouth may be caused by illness, medications, radiation therapy and chemotherapy, and may be either temporary (days to months) or permanent, depending on its cause.
A crown is a type of dental restoration which completely caps or encircles a tooth or dental implant. Crowns are often needed when a large cavity threatens the ongoing health of a tooth. They are typically bonded to the tooth using dental cement. Crowns can be made from many materials, which are usually fabricated using indirect methods. Crowns are often used to improve the strength or appearance of teeth.
The most common method of crowning a tooth involves using a dental impression of a prepared tooth by a dentist to fabricate the crown outside of the mouth. The crown can then be inserted at a subsequent dental appointment. Using this indirect method of tooth restoration allows use of strong restorative materials requiring time consuming fabrication methods requiring intense heat, such as casting metal or firing porcelain which would not be possible to complete inside the mouth. Because of the expansion properties, the relatively similar material costs, and the aesthetic benefits, many patients choose to have their crown fabricated with gold.
As new technology and materials science has evolved, computers are increasingly becoming a part of crown and bridge fabrication, such as in CAD/CAM Dentistry.