Dental Inlays vs. Onlays: Key Differences Explained

If you had a cavity at your last dental appointment, you're not alone. Studies show that about 90% of adults over the age of 20 have had at least one cavity.¹ And when it comes to treating a cavity, most of us are familiar with the idea of a filling, which is used to “fill" in an area of your tooth that has decayed. But did you know there are multiple types of treatment options available?

Besides the traditional filling, your dentist may consider two other dental restoration options: an inlay or an onlay, also known as indirect fillings.²

Dental Inlays vs. Onlays: What's the Difference?

A dental inlay may be recommended if your cavity is in the center of your tooth or within the grooves of your tooth.² A dental onlay, also called a partial crown, may be recommended if you have a cavity or more extensive tooth decay that spreads to your tooth's edge or biting surface.²

Sometimes used as an alternative to a full dental crown or traditional tooth filling, inlays and onlays typically fit better and are a stronger, longer-lasting option. Fillings are molded into place during a dental visit, while inlays and onlays are premolded in a lab and then fitted and bonded to your tooth.² It has been shown that traditional fillings weaken the tooth structure more than inlays and onlays.³

How Much Do Dental Inlays and Onlays Cost?

The costs of dental inlays and onlays are comparable. The average cost of dental inlays ranges from $250 to $1,500, and the average cost of dental onlays ranges from $350 to $1,500.²

This price varies depending on factors such as:

• Dentist experience
• Geographic location
• Tooth location (back teeth can be more difficult to work with than front teeth)
• Type of material
• Size of dental inlay or onlay²

Does Dental Insurance Cover the Cost of Dental Inlays or Onlays?

Many insurance companies cover all or part of the cost of fillings. Dental insurance companies categorize inlays and onlays as either basic or major, which affects how much of the treatment may be covered. The basic category typically covers routine dental services and fillings. If they are considered a major category by your insurance company, you may only be reimbursed for a percentage of the cost.²

Benefits of Inlays and Onlays

Inlays and onlays typically last longer than traditional fillings — in some cases up to 30 years.³ But there are other reasons why you may choose a dental inlay or onlay over a traditional filling.

• Tooth structure: If you have minimal to moderate tooth decay, this option can help preserve as much of your healthy tooth as possible and doesn't require reshaping of the tooth.
• Tooth strength: The stability of the inlay and onlay can help strengthen a damaged tooth.
• Ease: The fit and overall procedure results in a better-fitting filling, which makes your tooth easier to clean and helps seal out bacteria if the cavity is in between two teeth.
• Aesthetics: Inlays and onlays are less likely to discolor over time.²

Different Filling Materials

Whether you're considering a traditional filling, inlay or onlay, there are often several dental filling materials to choose from, each with their own advantages and disadvantages.³

What to Expect When Getting a Dental Inlay or Onlay

It usually takes two visits to get a dental inlay or onlay because, during the first dental visit, your dentist has to get a molded impression of your tooth to send to the lab that will create the actual piece to put in your tooth.

In the first visit, your dentist will numb the area around your tooth with a local anesthetic and use a drill, laser or other instrument to remove the decayed area. Next, your dentist will use either a putty-like material or digital device to get the impression to send to the lab. They will then put in a temporary filling until the permanent inlay or onlay is ready.²

At the second appointment, your dentist will remove the temporary filling and bond the permanent filling to your tooth.³

The procedure itself is very similar to having a traditional filling in that you don't need anyone to drive you home from the procedure, but you may experience some tooth sensitivity or a little bit of pain afterward. If you experience either of these and it's either extreme or symptoms don't resolve in two to four weeks, it's advised to call your dentist.³

New fillings rarely fall out, but results may vary depending on your dentist's experience, your individual situation and the type of material used.³

Financing Inlays and Onlays With the CareCredit Credit Card

Whether you're getting an inlay, onlay or you simply need a dental exam, the CareCredit credit card can help you pay for costs not covered by insurance.^* Apply today and use our Acceptance Locator to find a dentist or oral surgeon near you that accepts CareCredit. Use the CareCredit credit card, again and again, to pay for your health and wellness needs, and download the CareCredit Mobile App to manage your account, find a provider on the go, and easily access the Well U hub for more great articles, podcasts, and videos.

Author Bio

Abbie Mood is a freelance writer with more than 10 years of experience. She has worked with clients of all sizes to create compelling content and she has written for the American Kennel Club, Marriott Bonvoy, Women's Health Online, Headspace and more.