|Crowns for Primary (Baby) Teeth|
A crown is a cover placed over the entire tooth that is made to look like a tooth. It is used for teeth that are badly damaged or decayed. Many people call this a "cap."
It's important to try to save primary teeth until they are ready to fall out on their own. Primary teeth are important for several reasons:
- Chewing food
- Allowing speech to develop normally
- Maintaining spaces for the permanent teeth
- Guiding the permanent teeth into position
A cap is one way to treat severe tooth decay. If decayed primary teeth are not treated, the infection can spread in the mouth. Pain and infection can lead to other health problems as well.
Molars are the teeth in the back of the mouth. They are used primarily for chewing. There are eight primary molars. Dentists will use a crown on children's primary molars in several cases:
- When a primary or young permanent tooth has extensive decay, often on three or more surfaces
- When a filling would be very large, because large fillings can weaken the tooth and make it more likely to break
- When a primary tooth has not developed normally
- When a child with high levels of decay has special needs or poor oral hygiene habits. In this case, the crown will protect the tooth from further decay.
The front teeth include the incisors and canines. They are used primarily for biting. There are four primary incisors and two primary canines in each jaw (upper and lower). Dentists place crowns on these front teeth when:
- There are large areas of decay on several surfaces.
- The tooth has undergone root canal therapy (endodontic therapy).
- The tooth has been broken and part of it has been lost.
- The tooth did not develop normally.
- The tooth is discolored and the parent or child is concerned about how it looks.
Your child may need a crown even for a relatively small cavity in a primary tooth. That's because primary teeth are smaller than permanent teeth and have thinner enamel (outer layer of the tooth). A crown may be needed to strengthen the tooth and protect it from breaking or cracking.
Pre-formed, stainless steel crowns are the most common crowns used in primary teeth. They are made as metal shells of varying sizes that can be customized to fit any tooth.
These crowns have been used in children for 50 years. They are durable and relatively easy to place.
Because a crown covers the entire tooth, it protects it from decay. Studies have shown that stainless steel crowns are about half as likely as amalgam fillings to need replacement.
Other types of crowns used in children's teeth include:
Strip crowns — These also are called acid-etched resin crowns. They are usually used for front teeth that need repair. They are made using a form that is filled with a tooth-colored plastic material and placed over the tooth. The durability of a strip crown depends on how much tooth is left and how well the tooth was prepared for the crown. Injury to the tooth can break, loosen or dislodge this type of crown.
Open-faced steel crowns — The front area of a steel crown is cut away and replaced with tooth-colored plastic. These crowns look nicer than stainless steel crowns, but some metal usually shows at the edges and on the back of the tooth. These crowns are very durable and stay in place well.
Veneered steel crowns — These crowns have a tooth-colored face bonded to the front. They look good and last well. However, the facings occasionally break or pop off.
Zirconia crowns — Zirconia is a hard, tooth-colored material similar to ceramic, but stronger. Like stainless steel crowns, zirconia crowns are pre-made to specific sizes. The teeth are adjusted to the crown. These crowns cost more than stainless steel crowns. They are most often used for the front four to six teeth.
In adults, crowns are placed during several visits. Children usually can get a crown during a single visit.
The dentist will rub an anesthetic gel or cream on a small area of the gum or inner cheek. Once the area is numb, the dentist will inject a local anesthetic. This will numb the area of the mouth where the crown will be placed.
After giving the local anesthesia and any sedation, the dentist will put a dental dam on your child's teeth. This is a piece of latex or similar material that isolates the tooth your dentist is treating. A hole is punched in the dam so the tooth comes up through the hole. The dam protects the rest of the mouth.
Dams come in latex and latex-free materials. Some dental dams are scented or flavored.
The dental dam has several advantages:
Removing decay and shaping the tooth
- It keeps the cheeks, tongue and lips out of the way of the procedure and protects them.
- It keeps saliva away from the procedure. Most of the materials that dentists use are more effective if kept dry. In some cases, saliva can weaken a filling.
- It prevents the child from accidentally swallowing or choking on anything during the procedure.
- It makes many children feel safer to have a dental dam between them and the dentist.
The dentist will use a special drill to remove the decay and shape the tooth so the crown will fit over it. This drill is called a handpiece. First, the dentist will reduce the chewing surface of the tooth, and then the sides that touch other teeth. Your dentist will place the smallest possible crown. However, it must touch the neighboring teeth to help keep them in line and prevent problems in the bite (the way the teeth come together).
Once the tooth is prepared, the next steps depend on the type of crown. Your dentist will test any crown to make sure it fits the tooth. Then the crown will be shaped to fit as closely as possible. In the case of a strip crown, your dentist will size and shape a mold (called a crown form) for the tooth.
Once a stainless steel or open-faced crown fits the tooth, it will be polished and filled with cement. Then it will be pushed into place on the tooth. For an open-faced crown, the dentist will cut away the front of a steel crown and replace it with a tooth-colored material.
If your child is receiving a strip crown, the tooth will be etched with a weak acid. This will allow the crown to hold on more firmly to the tooth. The crown form will be filled with plastic and placed on the tooth. The plastic will be hardened by a special light. Once the plastic is hard, the crown form will be removed, leaving a plastic crown behind.
When the crown is placed on the tooth, your dentist will remove any extra cement or plastic, rinse your child's mouth, and examine the tooth and surrounding area.
Finally, your dentist will make sure the bite is correct.
Your child may have some mild discomfort after a crown is placed. This usually is caused by irritation of the tooth's pulp or the soft tissue around the tooth. The discomfort usually goes away after the first 24 hours. If your child complains of pain for several days, contact your dentist's office. Over-the-counter pain medicines can help.
After receiving a crown, a child sometimes may accidentally chew, suck or bite on the numbed area because it feels swollen. This can cause significant injury. With the area numb, the child will not realize how hard he or she is biting. The dentist should warn your child not to do this. You also should watch your child until the anesthesia wears off.
Ideally, your child should not eat until the numbness goes away. However, if your child is very hungry, feed him or her only soft foods until the numbness goes away. This can help to prevent accidental bites on the lip or cheek. After feeling is restored, your child can eat normally.
Pay attention if your child complains that his or her teeth don't come together right, or that biting "feels funny." The crown may need to be checked to make sure it is not higher than the other teeth.
All of the following problems occur only rarely.
Stainless steel crowns — The cement could wash out and the crown could become loose.
Strip crowns — These crowns can chip or break or become dislodged, especially after injury to the tooth.
Open-faced steel crowns — The plastic face could chip, or the cement could wash out and dislodge the crown.
Veneered steel crowns — The veneer can chip or fall off, or the crown can become loose or fall off.
Zirconia crowns — This type of crown can fracture or fall off.
It's important for your child to visit a dentist, usually twice a year. Children who have a high risk of cavities should be seen as often as four times a year. Children with crowns typically would be considered high-risk. During the examination, your child's dentist will check to make sure the crown is still in place, has not become loose, and has not been damaged.