Crowns are full coverage restorations that are used to cover a tooth that is likely to break or that is too broken down to be restored with a filling. They are most commonly done after root canal treatment, or when a large filling wears out. The larger the hole made by a cavity that has to be treated, the more likely a crown will be needed. Even after a filling is put in a large cavity, a tooth is more likely to break. Keep in mind that the jaw muscles are the strongest in the human body. Teeth are subjected to tremendous pressures. Crowns ride over the weakened tooth, providing strength and protecting the tooth against breakage. A broken or cracked tooth is a far more serious matter and much more difficult to treat. Crowns prevent this, and make for a nice smile!
It takes two appointments to restore a tooth with a crown. In the first, any decay is removed from the tooth and it is shaped to accept the crown. Then an impression is made of the tooth for use in fabricating a crown. Between the two visits, the crown is made, usually of high-strength porcelain over a gold alloy, all ceramic material, or gold. During this time a temporary crown is worn. In the second visit, this temporary is removed. Then the permanent crown is adjusted as needed and then cemented in place.
There are different types of dentures, but they share their common function. They replace teeth that have become loose or been lost due to bone loss. When bone loss around the roots of teeth is great enough to loosen them or let them fall out, it's time for dentures. Relax. No one enjoys losing their natural teeth, but you can still eat and talk regularly.
The entire mouth is examined and a determination is made as to which teeth will have to be removed, and which will remain. The loose teeth are then extracted. Dentures are fitted to go over or around whatever teeth remain in the mouth, depending on the type. There is an adjustment period after dentures are placed in the mouth, and it can take some getting used to. But once accustomed to the dentures, all the normal functionality and appearance return and one just carries on as usual. Often implants can be used to further stabilize the dentures.
Fillings are done to remove decay and replace the affected tooth structure. It is called a filling because new material fills holes that decay left. These days, most teeth are treated with bonded, tooth-colored, composite resin fillings. Caught early enough, cavities can be treated easily and painlessly. If not treated, decay can lead to tooth pain and/or infection, and the tooth would need root canal treatment or extraction.
Bonding involves adhering composite resin material that is matched to the color of the tooth to the front of the tooth. This is done to repair damage done to the tooth by decay, to alter the alignment of the tooth, close gaps between the teeth, or for cosmetic purposes. First the surface of the tooth is roughened in order to accept the bonding and hold it. A gel is applied to microetch the tooth surface, and a primer/bond agent is applied so the material adheres to the surface. Then the material itself is placed on the tooth and hardened with intense light. The composite resin material is shaped and polished to get a lustrous finish as a last step.
Root Canal Treatment
Root canal treatment (also referred to as root canal therapy or endodontic therapy) is made necessary when a cavity is allowed, through neglect, to reach all the way to the pulp (regular cleanings and checkups prevent and detect problems early). Sometimes, deep restorations or trauma to a tooth may cause the nerve to be damaged to the point it needs root canal therapy. Once this occurs the pulp becomes infected and can extend through the root tip and begin to eat away at the surrounding bone (this is an abscess). By the time the pulp is infected, it must be treated and cannot heal on its own. It can even weaken the entire immune system. This is dangerous - not to mention very painful. Symptoms that the pulp has become infected may include sensitivity to hot/cold or sweets, pain, swelling, pain to biting or pressure, and a bad taste in the mouth. Sometimes, however, no symptoms are apparent and the person is unaware of any problem until a checkup.
A root canal is then performed to clean out the infected tooth pulp and disinfect the canals of the tooth. The only other treatment would be to extract the tooth. Once the infection is resolved, the canal is filled in to prevent any further infection. Usually, a core build-up and crown are recommended for restoring a tooth that has had root canal therapy.
This is an option for filling the space created by a missing tooth. It is formed to look like the missing tooth and it takes its place in the mouth. The sides of a bridge use the two surrounding teeth for support - hence the name. A bridge replaces the missing tooth, both functionally and cosmetically. Bridgework is as much an art as it is an exact science. The materials used may be gold alloys, porcelain bonded to metal alloy, or all ceramic material. The choice of material depends on requirements for strength, wear, and/or aesthetics.
It is important that a missing tooth be replaced as soon as possible for several reasons. If not treated the teeth surrounding the gap begin to shift inward, creating a chain reaction of bad things. Teeth use their neighbors for support, and, with one missing, they start to "fall." As this worsens the bite changes in response to the pressure. This can eventually result in problems with the entire jaw, such as TMJ disorder. The surrounding teeth deteriorate and it is only a matter of time before they, too, are lost. Gum disease becomes a serious problem, with the difficulty of treatment increasing as the neglect continues.