A dental crown is a covering for a damaged tooth. It helps to restore the normal shape, function and size of the tooth.
Crowns don’t last forever, but you can extend the life of a crown by taking the proper precautions.
In this article, we’ll take a closer look at the different types of crowns and their longevity, as well as the warning signs that a crown may need to be replaced.
According to American Dental Association (ADA), if you have a large filling but not enough tooth left to hold it, a crown can help strengthen the tooth.
Your dentist may also use a crown to:
- restore a broken or cracked tooth
- protect a weak tooth from breaking
- attach dental bridges
- protect a fragile tooth following a root canal
Dental crowns can be made from a variety of materials, some of which last longer than others.
“The average lifespan of a crown is about 10 years,” he says William D. Cranford, Jr.DMD, of Cranford Dental.
But when properly made and cared for, he says crowns made of any material can last for decades.
When it comes to the type of crown to use, Cranford says your dentist will consider the strength, durability and aesthetics of each material when deciding which crown is best for your particular situation.
Other factors your dentist may consider when deciding on the best crown material for your tooth include:
- the position of the tooth
- how much of the natural tooth still remains
- how much of the crown will be visible when you smile
Let’s look at the four most commonly used crowns and their expected longevity.
Zircon
Zirconia crowns, categorized as a type of ceramic crown, are made from zirconium dioxide, a very strong type of material related to titanium. The durability of these crowns makes them extremely resistant to breakage.
According to Cranford, zirconia is the strongest non-metallic material for crowns. However, he explains that zirconia crowns don’t always fit as well as other crowns.
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With proper oral hygiene and care, a zirconia crown can easily last 10-15 years — or longer.
Porcelain fused with metal
“Porcelain-fused-to-metal crowns have been the most commonly prescribed cosmetic dental solution for the past 60 years,” explains Cranford. “However, porcelain is prone to chipping, and over time, the metal fringe or edge often appears as the gums recede.”
That said, he points out that these metal-backed restorations still have a place in dentistry, particularly for bridges that replace missing teeth.
On average, PFM crowns are expected to last from 5-15 years. With good dental care, they can last longer.
Lithium bisilicate
This material is a strong type of glass-ceramic that is made from lithium (a silver-white metal) and silicon (a hard, crystalline solid).
Dentists can use lithium bisilicate to make crowns in the office with a specialized unit. This means you can have a crown made and permanently placed in just one office visit.
Cranford says that, currently, dental labs report this as the most commonly prescribed crown material.
“Lithium bisilicate is very strong and can be adjusted for translucency,” says Cranford. “These crowns are cosmetically attractive, fit well on the margins and bond well to the teeth.”
These crowns also last at least 5-15 years – or longer – with proper care.
Gold
“Yellow gold has been the material of choice for crowns for over 100 years,” says Cranford. This is due to its strength, resistance to chipping and cracking, and its ability to fit the tooth well.
Actually, a Literature review 2015 found that gold is still the “gold standard,” with a 95 percent 10-year survival rate. With proper care, it is possible for a gold crown to last for decades.
One drawback to using gold, however, is its unnatural appearance. Dentists usually consider gold for molars that are not visible when you smile.
Dentists today often combine gold with other metals, such as palladium, chromium or nickel. This helps keep the crown strong, but reduces its cost.
The main difference between a veneer and a crown has to do with coverage. A dental crown covers the entire tooth, but a veneer only covers the front part of your tooth. There is also a difference in thickness, with a crown being thicker than a veneer.
Depending on the material used and your dental habits, the lifespan of a veneer versus a crown is similar, but veneers may not last as long because they are thinner.
In general, a veneer is recommended for cosmetic purposes. But if you have any decay, cracks or excessive wear, a crown will be more beneficial. Your dentist will be able to determine which restorative procedure is right for you.
According Michael H. ReshadDDS, of Sutton Place Dental Associates, the only way to know if a crown needs to be replaced is by a physical exam or dental x-ray.
“If caries is visible, either clinically or radiographically, the crown should be replaced,” he says.
Reshad also says that if there are open margins where the crown is not properly seated on the tooth, or if there is a gap between the crown and the tooth, the crown should be changed.
Also, if the crown is broken or there’s a space between the crown and adjacent teeth that allows food and bacteria to build up, it’s a sign that the crown needs to be replaced, Reshad explains.
Some of the warning signs that a crown may be nearing the end of its life include:
- Pain involving the tooth with the crown. “Most likely, tooth decay is the culprit,” says Reshad. As a result, the crown must be removed along with the decay underneath, and a new crown will be fabricated and placed, he explains.
- A feeling that the crown is unstable or seems to move. Reshad says this can happen when you chew something sticky, like gum, candy, or even bread.
- The tooth with the crown is no longer aesthetically pleasing. Reshad says some patients like to have whiter crowns, especially if adjacent teeth have been bleached. They may also want to create a different shape or look. Also, if a crown is chipped, a patient may want to have it replaced.
The lifespan of a crown can vary depending on the type of material used, as well as your dental hygiene habits and other lifestyle factors.
According to Reshad, the most important factor in a crown’s longevity is a good oral hygiene program. This includes:
According to Reshad, other factors that can affect the longevity of a crown include:
- The crown type. The quality of the crown, how well it is made, and the material used to make it can all play a role in the longevity of the crown.
- Dentist skill set. Certain factors, such as how well the dentist prepared the tooth and how they took the impression or scan of the tooth, can also make a difference in the life of the crown. Using a digital scanner is more accurate than tray impression materials for a single tooth.
- Health of the affected tooth. If the tooth was relatively healthy with longer roots and healthier levels of gum and bone, both the crown and the tooth will likely have a better prognosis.
- Using your teeth as tools. Using your teeth to peel off bottles or tear threads, or to chew ice and pencils, can negatively affect the longevity of a crown.
- Grit tooth. Clenching and grinding your teeth, especially at night, can wear down the surface of the crown and compromise its stability, especially if it is made of ceramic material. You may want to ask your dentist about a mouth guard that you can wear while you sleep.
Depending on the type of dental material used, the average lifespan of a crown is around 10-15 years. However, with proper care, good dental hygiene habits and regular dental checkups, some crowns can last for decades.
Your dentist can talk to you about the cost, durability, and other pros and cons of each type of material to help you determine the best type of crown for your needs.
