How are cavities filled?

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Filling a cavity is typically a quick process that can help restore the look and functionality of your smile.

Have you ever had a cavity? Over 90% of Americans over 20 have had cavities at some point in their lives¹. While it’s always best to prevent cavities from ever forming in the first place with proper oral hygiene, if you already have a cavity or two, you’re probably going to need a filling.

If it’s been a while since you’ve had a cavity filled, you might be wondering how cavities are filled and how long does a cavity filling take.

How long does it take to fill a cavity?

Simply put, a cavity is a hole in your tooth. It can occur when your tooth enamel, the hard, outer layer of your teeth, starts to break down due to plaque and bacteria².

Early-stage cavities can look like a white spot on your teeth, while larger cavities will typically look like a brown or black spot. Cavities that are not fixed can cause tooth sensitivity and tooth pain. Cavities left untreated are likely to require more serious treatment like a root canal or even oral surgery to remove infection.

While brushing, flossing, visiting the dentist regularly for cleanings, and avoiding sugary foods can help to prevent cavities, practicing good oral hygiene may not be enough to make cavities go away. Once a cavity is formed, a dentist must remove the tooth decay and fill the hole.

A cavity filling is one of the most common ways of treating cavities. This procedure is just what it sounds like – a dentist fills your tooth with some sort of material to relieve pain or sensitivity and restore your tooth. First, your dentist will remove surrounding decay or damage with a drill or laser to get rid of bacteria, then your dentist will fill the cavity with resin-based composite (also known as tooth-colored filling), dental amalgam, porcelain, or gold filling.

How long it takes to fill a cavity will depend on the severity of your cavity, the location of your cavity, and the type of filling you get.

Of course, even after your cavity is filled and you leave your dentist, you’ll still have to take good care of your teeth by brushing and flossing regularly. If your filled tooth is sore, brush and floss gently around it as instructed by your dentist. If your tooth continues to be sensitive for days afterward or if you feel a pointy edge near the filling, contact your dentist. There may be a problem with your filling, or you may be having an allergic reaction to the filling materials used.

What does a filling look like?

How your filling looks will depend on the size of the cavity, the location of the cavity, and the type of filling you and your dentist choose to get. Since the purpose of a filling is to fill the hole created by tooth decay, a large filling might be rather noticeable while a small filling might be easy to miss. Plus, some fillings are meant to blend in with the rest of your teeth while others are easier to spot.

However, no cavity filling lasts forever. Most fillings typically require replacement at some point. If you notice a foreign object in your mouth after biting down on something hard, you notice a hole in your tooth left by a lost filling, or you’re experiencing pain and sensitivity in that tooth again, chances are your filling fell out. What does a filling look like when it falls out depends on the type of filling you got in the first place and the size of your cavity – it might be white, gold, or silver, and it will likely take the shape of the hole in your tooth. If you suspect your filling fell out, call your dentist right away to schedule an appointment to replace it.

How are cavities filled between teeth?

Cavities can form anywhere on your teeth, including in the space between two teeth. These cavities are known as interproximal cavities.³ They usually require a two-surface filling and can be more difficult to fill.

It’s best to prevent these cavities from forming in the first place by regular dentist visits, cleaning between teeth daily and limiting sugar intake. But if an interproximal cavity has already formed, there are typically a few ways to treat it depending on the severity of the cavity. Your dentist may recommend one of five treatment option⁴:⁵

  • Fluoride recalcification - If your cavity is caught relatively early and decay has only extended halfway into your enamel, your dentist may be able to use fluoride gel to promote recalcification.

  • Filling - If the cavity extends further into the enamel, your dentist may perform a filling to restore the tooth. Your dentist will drill the tooth to remove decay, then fill the cavity with resin-based composite, gold, or silver.

  • Root canal - If the cavity is severe and untreated, your dentist may have to perform a root canal to remove the tooth’s pulp and clean the inside of the tooth.

  • Crown - If the cavity has gotten so large that there is not much natural tooth remaining, your dentist may use a crown to cover and support the tooth.

  • Extraction - If your cavity has spread to the pulp of your, your dentist could recommend removing the tooth and replacing it with an implant or dental bridge.

How much are white cavity fillings?

The two most common types of tooth fillings are resin-based composite fillings and dental amalgam fillings. Also known as white cavity fillings or tooth-colored fillings, resin-based composite fillings typically blend in with your teeth and look more natural. They are typically made up of a mixture of plastic and glass or quartz filler. They’re an attractive, durable option for small- to mid-size fillings. They typically cost more than traditional dental amalgam fillings since they require a more complex process and more expensive materials. The cost difference isn’t always covered by insurance. Resin-based composite fillings cost on average $135 to $325⁶ per filing.

Dental amalgam fillings are typically made up of a mixture of mercury, silver, tin, and copper. They’re more noticeable than white cavity fillings since they look silver and metallic. However, they also last longer. They’re less expensive than white cavity fillings, costing on average $110 to $275 per filling⁷.

Porcelain is another less common type of white cavity filling that can be used. It’s typically more expensive than resin-based composite fillings. Gold fillings can be used as well, though they aren’t as common since dental amalgam is more affordable and gold fillings are still just as noticeable.

Of course, the cost of a filling isn’t typically the only expense you’ll have to take into account. You’ll also want to take a close look at what types of fillings your dental insurance will cover and at what percentage. Plus, X-rays and anesthesia if needed as per your dentist, can sometimes come at an additional cost aside from the filling itself. Discuss your options with your dentist and review your insurance policy carefully before making treatment decisions.

The cost of fillings without insurance can be expensive. Since cavities are so common, it might be a good idea to look into getting dental insurance to help save money on future treatment costs if you don’t have a policy already.

How are cavities filled in front teeth?

Cavities in front teeth are filled in much of the same way as interproximal cavities or posterior cavities. Depending on the severity of the cavity and the tooth decay, your dentist might recommend a fluoride treatment, filling, root canal, crown, or even tooth extraction.

However, getting a cavity filled in your front teeth might bring up different concerns since these teeth are more visible when you speak and smile. If you’ve noticed visible pits and holes in your front teeth or if you experience sharp or mild pain while eating hot, cold, or sweet foods, schedule an appointment with your dentist to get your front teeth cavities taken care of. For cosmetic purposes, you may want to opt for tooth-colored fillings like resin-based composite or porcelain to restore your smile.

How long does it take to fill a cavity – filling insights

Interested in learning more about what to expect when getting a cavity filled? We’ve compiled a few resources full of advice, tips, and insights to help you learn more about procedure costs, treatment options, prevention, and ways to save money on cavity fillings.

Does insurance pay for dental fillings?

What is a cavity?

What does dental insurance cover?

How to buy dental insurance: the first 4 questions to ask

A comprehensive guide to dental insurance

How much is dental insurance?

Why some dental insurance plans have no waiting periods

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Brought to you by The Guardian Life Insurance Company of America (Guardian), New York, NY. Material discussed is meant for general illustration and/or informational purposes only and it is not to be construed as tax, legal, investment or medical advice. This is not dental care advice and should not be substituted for regular consultation with your dentist. If you have any concerns about your dental health, please contact your dentist's office.


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