What determines the cost of cavity treatment?
Three things. Even for the same “one cavity,” the price can differ several times over depending on these conditions.
- Size and depth: if it is small, it is filled on the spot (composite filling); if it is large, an impression is taken and a piece is made and bonded in (inlay), or the whole tooth is covered (crown). If it reaches the nerve, root canal treatment is added.
- Location: the outer surface of a front tooth, the spaces between teeth, and the chewing surfaces of molars differ in difficulty and material requirements.
- Material: the difference between insurance materials (amalgam, GI) and materials not covered by insurance (composite resin, ceramic, zirconia, gold).
What treatment is done for each cavity size?
The larger the cavity, the bigger the treatment and the more visits it takes. I have explained the differences by stage separately in Why cavities differ at each stage.
| Extent of cavity | Usual treatment | Usual number of visits |
|---|---|---|
| Small cavity | Composite filling or GI filling | 1 |
| Medium size, between molars or on the chewing surface | Inlay (resin or ceramic) | 2 |
| More than half the tooth is damaged | Crown | 2–3 |
| Infection reaches the nerve | Root canal treatment, then a crown | 2–4 for root canal treatment + 2 for the crown |
How much are composite fillings, inlays, and crowns?
Wonjin Dental’s published prices are as follows (as of September 2026, per tooth). The VAT-included notation applies to cosmetic treatment items.
| Treatment | Area / material | Price |
|---|---|---|
| Composite filling | Premolar / lingual surface of front tooth (inside of front tooth) | ₩100,000 |
| Composite filling | Molar / cervical (neck of the tooth) | ₩150,000 |
| Composite filling | Proximal surface (between teeth) / labial surface (outer surface of front tooth) | ₩300,000 |
| Inlay | Resin / ceramic | ₩300,000 / ₩350,000 |
| Crown | Back tooth PFM / back tooth zirconia / back tooth gold | ₩400,000 / ₩500,000 / ₩800,000 |
| Crown | Front tooth zirconia / front tooth ceramic | ₩700,000 / ₩800,000 |
You can see all items in Full fee list. Composite fillings between teeth are more expensive because building up a wall to create the shape is a demanding process and takes a long time.
How much of cavity treatment does national health insurance cover?
For adult cavity treatment, insurance (Korean National Health Insurance) covers amalgam and GI (glass ionomer) fillings, root canal treatment, and extractions. Tooth-colored composite fillings are covered only for permanent teeth in children aged 12 and under; adult composite fillings, inlays, and crowns are not covered by insurance. Insurance for those aged 65 and over applies to implants and dentures, not to crowns.
GI is tooth-colored but weaker, so it is mainly used in places with little chewing force, such as the neck of the tooth. Ask during your consultation, with the reasons, whether a given spot can be done with an insurance material or needs a material not covered by insurance.
How much more does it cost if root canal treatment is needed?
Root canal treatment itself is covered by insurance, so the burden is not large, but it usually leads to a crown, which raises the total cost.
- Root canal treatment (endodontic treatment): national health insurance
- Resin core (a build-up that fills the broken-down part): ₩100,000
- Post (a reinforcing post placed inside the root, only when needed): ₩150,000
- Crown: amounts in the table above
I have summarized the number of visits and the process for root canal treatment in How many visits does root canal treatment take? In the end, treating a cavity while it is small is the cheapest way to treat it.
How we do it at Wonjin Dental
Wonjin Dental publishes its fees for treatments not covered by insurance as a price list. Before treatment, I explain for each cavity which treatments are possible, whether that spot can be done with an insurance material, and how the costs add up. If several methods are possible for the same cavity, I explain the pros and cons of each and let you choose.
Frequently asked questions
Isn’t amalgam harmful to the body?
The basic position of the dental profession is that set amalgam is stable and does not cause health problems in ordinary use. However, its color is noticeable, and there are recommendations to prefer other materials for pregnant women and children. There is no need to deliberately remove amalgam fillings that are in good condition.
Can several teeth be treated at once?
Several small cavities on the same side are sometimes treated in one visit. However, considering the area of anesthesia and which side you chew on, we often do not treat both sides at the same time. We simply set the order starting with the most urgent tooth.
How long do composite fillings last?
They usually last about 5 to 10 years, but this varies greatly with size, location, teeth grinding, and care. If the edges become discolored or a gap forms, decay can return underneath, so we check at your check-ups.
