Who performs this procedure?
While your general dentist is qualified to crown teeth, he or she may refer you to a prosthodontist. A prosthodontist is a dentist who has completed a university post-graduate specialty program in prosthodontics – which is a specialty of dentistry that deals with dental restoration, and the replacement of natural teeth and tissues with artificial substitutes.
Different types of crowns
Crowns are made from various types of materials. Depending on which tooth needs a crown, your dentist, or prosthodontist, will suggest a combination of materials that is right for you. Such as:
- Metal crowns are made of gold. They generally last a long time and won’t chip or break. They tend not to wear down your opposing natural teeth. However, the gold colour does not look natural, particularly on front teeth.
- Composite crowns look natural. They won’t chip as easily as porcelain crowns, but they tend to wear more quickly from chewing. Tooth brushing tends to remove the highly polished surface of composite crowns and this causes them to stain more easily.
- Porcelain crowns look the most natural. However, due to the fact that they are more brittle than metal or composite and may chip more easily, they are not usually placed on back teeth.
- Porcelain-fused-to-metal crowns look natural and are stronger than their porcelain or composite counterparts. They won’t chip as easily as porcelain or ceramic crowns. However, depending on their design, the metal may show if your gums are thin or shrink.
What else should I know?
Crowns are strong and generally last for about 10 years or longer, if properly maintained. Therefore, it is extremely important to brush and floss your crown, just like you clean your natural teeth. However, crowns may not be as strong as your natural teeth, so remember not to bite down on hard objects, or use your teeth to open or cut things.
When is a dental crown needed?
There are a variety of situations that require a tooth to be restored with a dental crown. The following are the most common:
- Large filling: When a tooth has a cavity or fracture that involves half the width of the tooth or more, it needs to be covered with a crown. This is because the remaining tooth around the large filling is so weak that it is prone to fracture. Sometimes a large filling that has been in the mouth for a while will need to be replaced with a crown because the tooth shows signs of stress and cracks around the filling.
- Root canal: Root canal treatment leaves the tooth hollowed out and predisposes the remaining tooth to cracking. So, a tooth that has had a root canal almost always needs to be restored with a crown immediately to prevent it from fracturing.
- Cracked-tooth syndrome: This is a condition whereby a patient has fractures inside a tooth that cause pain when chewing. Chewing produces stress on fracture lines that make it feel like it is splitting apart. A crown will hold the tooth together and redistribute the stress evenly throughout the tooth, eliminating the pain in most instances. In these situations, it is best to leave a temporary crown on for a while to make sure the pain goes away and the tooth doesn’t require a root canal.
- Broken cusps: Cusps frequently break off of teeth due to trauma or large existing fillings. Since the cusps are the part of the tooth that take the most stress during chewing, they need to be completely covered, or the tooth or filling will keep fracturing. Sometimes the tooth breaks all the way to the bone, and a crown-lengthening procedure is necessary. This means the bone and gums need to be trimmed down below the edge of the fractured part of the tooth, so the margin of the crown can be placed on healthy, strong tooth structure.