Dental crowns are one of the most durable restorative options. These tooth-shaped caps can be made from different materials and are placed for different reasons.
Below you will find a cheat-sheet on all things related, including a step-by-step rundown of the placement procedure. You will also be able to read about how long a crown might last and what to do if it causes you pain.Creative Commons
When are crowns recommended?
The reason for getting a crown is, most commonly, to cover up some other treatment, to improve aesthetics, or for support.
|Reasons for getting a dental crown|
|Covering up other treatment|
*If the reasons for getting a crown are purely cosmetic, then you may want to consider an alternative such as dental veneers.
A crown may cover the tooth fully or partially up to the gumline. This depends on the condition and health of the existing tooth and the reasons for getting the procedure. A crown can protect the existing dentition and prevent further damage.
You might wonder how long a dental crown can last. A 2009 study has found that 90% of crowns do not require any treatment for at least five years after the placement. Moreover, 50%-80% last from fifteen to twenty years.
This depends on how you care for it and the material it is made from. Some materials are more durable than others.
Types of crowns
Crown categories are determined by the material they are made from. That is a big factor in dental crown cost.
A dental crown made entirely of porcelain is referred to as “all-ceramic”. Nowadays it is the most popular type of crown.
The biggest advantage is that it provides great aesthetics. It can match the shape, size, and color of the surrounding dentition perfectly. That’s why it is recommended for replacing front teeth.
Dr. Namrita Harchandani
Dental crowns are the best way to protect the original natural tooth. With the advancements in dental technology and materials, very realistic crowns can be made that will make you forget that you even have one.
Porcelain is also biocompatible and toxic-free. This means it won’t cause an allergic reaction, as metal crowns sometimes do. The downside is that it is quite pricey.
Lithium disilicate is one type of porcelain. Some clinics have equipment that allows making such crowns in-office. This means the crown doesn’t need to be sent over to the lab, and that can save a lot of time.
Despite being the most expensive crown material, it is not the most durable. It can last a long time, but not quite as long as metal. What’s more, it does wear down the opposing tooth (the one it bites down on).
- Great aesthetics
- Lithium disilicate can be made in one visit
- Biocompatible and toxic-free
- Not the most durable
- Wear down opposing teeth
- Often can’t be done in one appointment
Zirconia dental crowns
Zirconia crowns combine the strength of metal and the convincing appearance of porcelain. Those suffering from allergies can also safely choose this material. It is biocompatible, so it doesn’t cause adverse reactions. Such crowns are becoming more and more popular.
They can also be layered with porcelain to further improve the appearance. If that is not done it can be difficult to match the exact color of the surrounding teeth, as zirconia is very opaque.
Dr. Sayeh Hadianfar
Progressive dental laboratories have solved the issue of the transparency of zirconia. They are able to match the shade of the patient’s other teeth.
Zirconia crowns can sometimes be milled at the dental office. This means it could be done in one appointment, or at least in one day. You may not need a temporary crown. What’s more, the material is very strong and requires less tooth preparation. It can be bonded or cemented, so the dentist has more options.
The downsides are that the material makes these crowns difficult to adjust, they’re expensive, and they do wear down the tooth they bite on. That being said, they are unlikely to wear down or chip themselves.
- Strong and durable
- Can look great
- Biocompatible and toxic-free
- Sometimes can be done in one appointment
- Less tooth preparation
- Difficult to adjust
- Wear down opposing teeth
- Often can’t be done in one appointment
Porcelain fused to metal crowns (PFM)
Porcelain fused to metal (PFM) means that the crown has a metal base and a top made of porcelain. The porcelain top allows the shape, size, and color of the surrounding teeth to be mimicked. It may not be the most popular, but it is widely used.
It is among the strongest and most durable and it is less costly than the all-ceramic or zirconia crown. But such a crown does have its drawbacks.
The biggest downside of PFM is a gray line between the tooth and gum that is sometimes visible. What’s more, if you are prone to clenching, it can chip or damage the opposing teeth. It can also cause allergic reactions.
This type of crown cannot be done in one visit like some of the ones described above. You will have to wear a temporary one.
- Shape, size, and color can be mimicked
- Strong and durable
- Less costly
- Grey line between the tooth and gum
- Can chip or damage opposing teeth
- Cannot be done in one visit
- Can cause allergies
- Need more tooth reduction
An all-metal crown is the strongest and most durable type, but it is not as aesthetically pleasing. While the shape and size of the surrounding teeth can be mimicked, the color remains different.
They are usually used for back tooth restoration. Some do, however, like this aesthetic and even go as far as engraving it or adding gems.
Unfortunately, all-metal crowns can cause allergic reactions. They are usually a mix of materials such as gold, chromium, palladium, and silver. The amount of gold in the crown can range from 20% to 77%.
Dr. Matthew Stewart
While it is technically possible, the likelihood of an allergic reaction is extremely rare. About 1 in 100,000. A metal crown is not advised against, unless the patient has a history of allergic reactions to dental work.
There are ratings that provide info on the metals used. The ratings are named “Base Metal”, “Noble Metal”, and “High Noble”. The last type has the highest percentage of gold. These crowns tend to be the best fitting and least damaging to opposing teeth.
The upside for these is that less of the tooth has to be removed than for other materials and they wear down at a rate similar to enamel. The downside is that they cannot be completed in one visit and you do have to wear a temporary crown.
- Strongest and most durable
- Shape and size can be mimicked
- Less of the tooth has to be removed
- Wear down less than other types
- Don’t wear down the opposing teeth very much
- Cheaper than other options
- Recommended for patients who grind
- Not aesthetically pleasing
- Can cause allergic reactions
- Cannot be completed in one appointment
A provisional crown is what you wear while you wait for your permanent crown. It can also be described as “temporary”. It is made from materials that aren’t meant to last very long and it is not permanently attached.
It shouldn’t be worn for more than a few months to a year at most. Most of the time it stays in the mouth for less than two weeks. The longer you wear it, the more problems it can cause.
A temporary crown is usually included in the price for the permanent crown. It is a necessary step if you have to leave the office before the permanent crown is ready, otherwise you could damage your living tooth.
The procedure of crown placement
The process of getting a crown can be divided into seven generalized steps. Some might not apply to every case. You will most likely have some sort of oral examination first, but after that it usually takes a few weeks to get a permanent crown.
Preparation of the tooth
The dentist will remove the decay, perform the root canal treatment, or both. The affected area will be numbed with a local anesthetic. The tooth will be shaved down as necessary.
Post and core buildup
You might need additional steps to build up your foundation, depending on the state of the tooth. The most common way is a post and core buildup. This is recommended for teeth which have suffered considerable decay. This step can sometimes be done at the same time as preparation or shaving of the tooth.
Making a mold or scanning the tooth
An impression can be made to make sure the crown fits perfectly. Some dentists prefer to use a scanner instead of the unpleasant putty. The opposing tooth can also be recorded so that the bite is comfortable.
Determining the shade
This can be done by using a shade guide or taking pictures of the teeth. It will help the lab technician make crowns that will match the rest of your teeth. In some cases the dentist may refer you to a ceramist for perfect shade selection.
A provisional crown will be made from resin or acrylic. It will come off easily when it is time to place the permanent crown. During this time be sure to avoid eating hard or sticky food, as the temporary crown can crack or fall off.
There might be a few weeks between placing the provisional crown and the next appointment.
Permanent crown placement
Lastly, the permanent crown will be placed and inspected for proper fit, bite, and smooth surface. Adjustments may need to be done, such as for the color or rough spots. Afterwards the crown will be attached by cement or dental glue. This is permanent and no more changes can be made.
Dental crown pain
You may feel some sensitivity after the anesthesia wears off. That is completely normal, especially for the surrounding gums. The dental cement can irritate them.
Dr. Peter March
If the tooth has a root canal, the nerves inside the tooth should all be gone. If the tooth does not have a root canal, the nerves maybe irritated for some time. As long as the irritation is getting better, it is normal.
You can use painkillers or topical anesthetic gel at this time to ease your discomfort. Toothpaste for sensitive teeth and gums is also a good idea.
The pain shouldn’t be severe or stretch over several weeks. If the tooth continues to hurt you should make an appointment with your dentist. Sometimes a simple adjustment is enough to solve the problem.
Removing crowns due to complications is rare. Usually it just takes some time for you to get used to it in your mouth. If, however, you feel long-term irritation or swelling, you could be allergic to the material, especially if it is a metal crown. That would be cause for removal.
How to care for your crown?
Crowns may not get cavities, but should still be cared for. You should maintain oral hygiene as you would with your natural teeth. That means brushing and flossing as per the dentist’s instructions.
There are some additional things you can do to try and make your crown stay in your mouth for as long as possible:
- Do not eat sticky or chewy foods (especially if your crown is not permanent.
- Avoid biting down on hard food or candy..
- Try to chew with the side of the mouth which is crown-free.
- When flossing slide by the neighbouring tooth, rather than lifting straight up.
How long does a dental crown last?
Longevity of crowns depends on the material they are made from, how well you take care of them, and its location. Porcelain crowns can last between 5 and 15 years while PFM ones last about 20. The most durable are all-metal crowns, and they can last over 20 years up to a lifetime.
What type of crown is best?
If you’re going for aesthetics, you are likely to be happy with a ceramic or PFM crown. The latter can sometimes show a grey line on the tooth-gum border, while the former are the most aesthetically pleasing.
All-metal crowns are cheapest and most durable. If you can’t afford to spend too much money and want a life-long solution, this type can be a great choice.
Is dental crown procedure painful?
Since an anesthetic will be used to numb the pain, you should feel no more than slight discomfort during the procedure. It is common to experience tenderness in the gums surrounding the crown.
This is because the dental cement can irritate them. Treat this with OTC painkillers and keep the area clean, the unpleasant feeling should subside within a few days.
Can your teeth rot under the crown?
Yes, especially if you don’t take good care of it. Decay around the edges of the crown can be easily detected. If treated soon enough, you might be able to keep your crown for many years. This is one of the reasons that bi-yearly exams are recommended.
What are the alternatives to a dental crown?
If the reason you want to get a crown is mostly aesthetic, you may be a good candidate for dental veneers. Part of the tooth is shaved off and a layer of resin or porcelain is placed on it to even out the shape, size, and color.
If you suffered slight trauma or decay in your tooth, an onlay might be enough. Some of your tooth is drilled away and a restoration made outside the mouth is cemented in place.
Fillings work similarly, except they are direct. This means amalgam or resin is used to build up the tooth after the damaged parts are removed. Composite restorations work similarly, and are a good choice if the tooth is not damaged by bacteria, but merely chipped or fractured.