Crowns
Your dentist may recommend a crown when a tooth has been decayed or damaged and cannot be restored to its proper shape, function and appearance through other means,. A crown is placed over a decayed or damaged tooth to restore its shape, size, and durability. When cemented in place, crowns fully encase the entire visible portion of a tooth that lies on and above the gum line.
Unlike fillings, crowns are created outside of the mouth. This process allows your dentist to better match the contours of your natural tooth. It also makes it easier for the crown to properly contact adjacent teeth so food won't collect between them.
Crowns can be made from a variety of materials, and the material used can impact cost, durability, and appearance. Your dentist will recommend options based on your particular needs.
Different ways of making crowns
Permanent crowns can be created in multiple ways. How your crown is made depends on the equipment your dentist has in their office and the material recommended for your specific needs. Some materials may be better suited for you than others. It's important for you to make an informed decision about the type of crown that is best for you versus the convenience of completing your procedure in less time.
Traditionally, technicians make permanent crowns in a lab. These technicians use impressions or 3D printed casts your dentist takes of your teeth and prepared tooth core. This method allows the crown to be made from the full array of materials available. The process can take up to a few weeks and requires two visits to the dentist.
Newer methods allow dentists to use a CAD/CAM machine to create a crown quickly in their office, so your crown can be placed in one visit rather than two (a "same day" crown). While this equipment eliminates the need for a second visit, the materials that can be used may impact how long your crown will last compared to those produced by traditional methods.
Crowns for primary teeth
Crowns for primary teeth differ significantly from crowns for permanent teeth in the way the tooth is prepared, how they are made, and the materials used.
How long do crowns last?
Current research suggests that dental crowns typically last between five and 15 years.1 Factors that can how long a crown will last include:
- The amount of wear and tear on the crown.
- Your oral hygiene habits.
- Changes in your nutrition or lifestyle.
- Medications that cause dry mouth.
- Stress or other conditions that cause a grinding or clenching habit.
- Aging.
- Using your teeth improperly.
Many people believe that crowns don't need as much care as natural teeth. This is incorrect. It's just as important to maintain good oral hygiene for your crown as you do for your natural teeth. Bacteria can still collect between the crown and the remaining part of the original tooth it covers, which can lead to tooth sensitivity, tooth decay, and failure of the crown itself.
The steps below describe the traditional process for a one-tooth crown. You should expect two office visits to complete the treatment. The first visit is to prepare your tooth and build a temporary crown. The second is to place your permanent crown once it has been made. Many of these steps are also part of the process to make a 'same day' crown. In either case, the time it takes to complete the procedure may vary if additional problems or complications arise.
Before the procedure
- Antibiotics: You may be pre-treated with antibiotics if you have certain types of heart conditions, heart valves, or replacement joints (for example, a knee or a hip).
- Review your health status: You will share information that will help ensure that your dentist and their staff can provide safe and effective treatment and provide appropriate post-care guidance. Get important information here: Health history and current health status.
- Treatment review: Your dentist will review the procedure with you, including its risks, benefits, and options. Understanding the process and any options you may have will lead to the best treatment outcome. Ask any questions you have before the procedure begins.
- Anti-anxiety medication: If you are anxious about dental procedures, your dentist may recommend sedation.
During the procedure
- Anesthetic: The tooth is usually numbed by injecting a local anesthetic around the nerve or nerves that supply sensation to the tooth. A topical numbing gel may also be applied to the site to help reduce discomfort from the injection.
- Preparing a temporary crown: Temporary crowns reduce tooth sensitivity and hold the tooth in the proper position while your permanent crown is made. Depending on the equipment your dentist uses, a pre-impression mold or digital scan of your teeth is made to prepare a temporary crown that you will wear before your permanent crown is ready to be placed. Its shape will match your original tooth and will be formed to fit over your prepared tooth.
- Shade matching: For a tooth-colored crown, your dentist will use a shade guide to ensure your crown matches the shade of your natural teeth. Dental porcelains and resins can produce a precise match of your natural tooth enamel, so your crown will match the teeth around it. If you are planning to have tooth whitening done, you should do so before the shade matching process.
- Tooth isolation: The tooth is usually isolated from your tongue and cheeks with a barrier known as a rubber dam. Other isolation devices may be used that incorporate suction and a means of comfortably holding your mouth open.
- Preparing the tooth:
- The tooth is prepared for the crown by removing the decayed or damaged areas and any existing dental work like fillings. Some parts of the tooth may also need to be filled in again. This is a separate dental procedure known as a core buildup.
- Your dentist will taper the walls of your tooth so that the crown can be slipped down over it. They will then create a margin around the tooth which the crown will seal tightly against. Sometimes a prepared tooth may not have enough tooth structure above the gums to hold onto a crown, resulting in the tooth's margin being located below the gums near the bone level. In these cases, the tooth may require a crown lengthening procedure.
- An impression of the prepared tooth: Your dentist will take another impression of the prepared tooth and the teeth that bite against it. They may move the gum tissue away from the prepared tooth with a thin cord, which will be removed after the impression is made. This process creates a crisp outline of the prepared tooth in the mold to help your dentist create a precise fit between the permanent crown and tooth.
- Creating the permanent crown: Your permanent crown is then made in a laboratory or by a CAD/CAM machine in your dentist's office for a 'same day' crown.
After the procedure
Your dentist will give you specific instructions on how to take care of your crown. You should request a copy of the instructions. Although the instructions may seem straightforward at the time of your dental appointment, you may have questions and need to refer to them later.
After you leave your dentist's office and while you are still numb:
- Do not eat or drink hot beverages while your lips, cheeks, or tongue are numb. It is possible to bite or burn yourself without realizing it.
- Do not pull on or poke at the numb areas in an attempt to make the feeling return. There is no way for you to reduce the period of numbness. Sensation usually returns within 1-2 hours, but the amount of time that passes until feeling returns depends on the type of anesthetic used and other factors.
- You may experience slight difficulty with speech until the anesthetic wears off.
Avoiding problems with your temporary crown
- Temporary cement is not as strong as permanent cement. It allows the temporary crown to be removed by your dentist without altering the prepared tooth core.
- Because the temporary cement is not as strong, temporary crowns can come out on their own. To reduce the risk of having your temporary crown come out, avoid chewing hard or sticky foods.
- When you floss, pull the floss gently out the sides between the temporary crown and your adjacent teeth. Don't pull it upwards.
- If a temporary crown comes out or breaks, your teeth may move to a slightly different position in the jaw. As a result, the permanent crown will not fit properly and may require adjustments or need to be remade. This movement can occur as quickly as 24 hours after your temporary crown comes out. Therefore, it is important to get it back into position as soon as possible. You should contact your dentist as soon as possible to schedule an appointment.
At your permanent crown placing appointment
- Placing the permanent crown: When your permanent crown is ready, you will make a second visit to your dentist. They will remove the temporary crown and replace it with the permanent crown (this second visit is not necessary if you decide to get a "same day" crown).
- It is fast and generally painless to remove your temporary crown. However, you may prefer or need sedation to avoid any discomfort with removing the temporary crown and cleaning the temporary cement from the prepared tooth.
- If your tooth is sensitive to hot or cold, you may require a local anesthetic for the procedure to be completed comfortably.
- Sometimes it is necessary to make small modifications to the tooth to get the permanent crown to fit properly. Depending on the nature of the modifications, your dentist may give you a local anesthetic before performing this procedure.
- If you have had root canal therapy on the tooth, you may not need a local anesthetic. However, you may still have your tooth and gums numbed to reduce discomfort when the permanent crown is placed.
- Adjusting and polishing the permanent crown: Once your permanent crown is in place, the bite between your crown and the opposing teeth may be adjusted slightly. Your dentist may also re-polish the crown. This process is called an occlusal adjustment and typically takes just a few minutes.
After the permanent crown is placed
It is common for a tooth with a new permanent crown to be sensitive to chewing and/or hot and cold temperatures for several days.
If it feels like your bite is not quite right a day or two following placing your permanent crown, it may be due to inflammation. Let your dentist know. They can help prevent the inflammation from spreading to the tooth ligament or pulp, which can cause further issues. If you experience severe sensitivity or discomfort, let your dentist know as soon as possible.
Your dentist may need to perform a minor bite adjustment if your tooth continues to be sensitive when biting. This is a minor procedure where your dentist will grind off a portion of the crown for a better fit.
Your dentist should explain any risks involved with treatment for a crown. You should ask any questions you have before the procedure is started.
- Tooth structure: Preparing a tooth for a crown involves reducing the sides of a tooth and its biting surface. When tooth structure is reduced, the tooth may lose some of its strength and cause future dental issues.
- Additional procedures: A tooth prepared for a crown may also need root canal therapy before or after a crown is placed. Whether a tooth will need a root canal depends on many factors, including:
- The extent of the damage or decay to the original tooth.
- If the crown was placed poorly.
- When you don't practice good oral hygiene and the crown fails.
- If the tooth becomes irreversibly inflamed following the tooth reduction procedures needed to complete the crown.
- When tooth decay has moved into the pulp chamber.
- Your age, health status, and habits.
- Tooth preparation:
- Inflammation and/or infection can occur when preparing a tooth for a crown. This is more likely to happen when preparing a tooth for a metal-ceramic crown since your dentist must remove more natural tooth to maintain the same strength as metal crowns.
- When a tooth is prepared for a crown, there is some risk that the nerve will become inflamed by the preparation procedure. This oftens depends on past decay or treatment on the tooth. If inflammation or pain occurs, additional treatments may be necessary. If your tooth has been experiencing problems before or during the crown placement, your dentist may cement the permanent crown with temporary cement for a brief time to see if the pain subsides. Once the tooth is determined to be stable, your dentist will use permanent cement to complete the crown placement. This can reduce the risk of having to treat a tooth's nerve after the crown is permanently in place but cannot entirely eliminate the risk.
- Other considerations:
- Crowns are more expensive than fillings but are generally better at stabilizing and preventing tooth fractures.
- Ceramic and composite resin crowns can chip, requiring repair or replacement. This is particularly true if you have the habit of grinding or clenching your teeth or using your teeth improperly.
- Crowns can fall out and be damaged or lost, making it necessary to replace them. Modern bonding adhesives and cements used in dentistry have significantly reduced this risk.
As a general rule, it is best to preserve tooth structure. So, it's important to explore alternatives to a crown that may allow you to retain as much of your original tooth structure as possible.
- A filling on one or more surfaces of the original tooth can often be a viable option to a crown. Fillings can help stabilize fractures and restore the tooth's normal contours, function and appearance without unnecessarily removing healthy tooth structure.
- In some cases, a bonded filling or core buildup can be placed in the tooth. These can last for quite some time but are generally considered to be temporary alternatives. With a bonded filling, the risk of a tooth fracture will be greater until your tooth is permanently covered with a crown.
- Temporary crowns can be semi-customized to your tooth, providing a short-term solution while you complete other dental procedures you may need. They may also offer an option to help you plan for the expense of a more permanent crown.
- An onlay may be an option if your tooth structure does not require a crown to hold it together. Your dentist will not need to remove as much tooth structure in order to place an onlay. Onlays can be made of metal, ceramic, or composite resin.
- Tooth removal and replacement with a dental implant may be a better long-term solution if your tooth is badly broken or decayed.
- An untreated tooth that needs a crown may continue to break apart until it cannot be possible to save it.
- A tooth in need of a crown may develop a crack that spreads through the tooth into the pulp. Bacteria can get into the pulp, causing an infection that may require root canal therapy.
- Are there alternative treatments to a crown that you can recommend? What are the pros and cons of those alternatives?
- How urgent is this treatment? What problems can occur if I wait until later?
- If I get a crown, what is my risk for needing a root canal in the future?
- What are the advantages and disadvantages of different crown materials, and which materials are best for me?
- Other than the convenience, what are the benefits of a same day porcelain crown in terms of durability, appearance, and cost versus crowns that are made in a laboratory?
- What symptoms should I expect after my crown? What symptoms should concern me, and what should I do if I experience them?
- How long will it take for the anesthesia to wear off, and are there ways to ease my recovery?
- What should I do if my temporary crown comes out?
- What hygiene recommendations do you have to be sure the crown lasts as long as possible
- How do I maintain good health around the crowned tooth?
Plan Coverage Disclaimer
Services described in this resource may not be covered by your dental plan. Your dental plan administrator may also place limits on services, or some of the services may be eligible medical plan expenses. Other services may be subject to review for dental necessity. This may affect the services your plan will cover and the amount your plan considers to be an eligible dental plan expense. Consider submitting a pre-treatment estimate before services are rendered. Please refer to your certificate for coverage details.
Last updated: 4/6/2021 • Medical review: Thomas J. Greany DDS, 12/22/2020
© Symbyos LLC. All rights reserved.