Fillings vs. Onlays vs. Crowns

What is the difference between a filling, an onlay, and a crown?

The three restorations sit on a scale of coverage. A filling replaces a small to moderate area of a tooth, an onlay replaces one or more of the tooth's cusps (the raised points on the chewing surface), and a crown covers the entire tooth above the gumline. The more of the tooth that is weakened, the more coverage it needs.

When is a filling enough?

A filling fits when the decay or damage is limited and the surrounding walls of the tooth remain strong. Dr. Lee removes the decay and fills the space with tooth-colored material shaped to match the tooth. Fillings are usually completed in a single visit.

When does an onlay make sense?

An onlay fits when damage is too large for a filling but much of the tooth is still healthy, such as when a cusp is weakened or broken. It is custom-made to replace the missing part and bonded to the tooth, so it reinforces the tooth without covering it completely. Onlays keep more natural tooth structure than a crown.

When is a crown needed?

A crown fits when most of the tooth is weakened, such as after a large break, extensive decay, or root canal treatment. It covers the whole tooth to hold it together and protect it from further cracking. Smile Art provides both same-day and lab-made crowns.

How do they compare?

How does Dr. Lee decide which one your tooth needs?

Dr. Lee evaluates how much healthy tooth remains, where the damage is, and the forces your bite places on the tooth, with X-rays to assess below the surface. She recommends the most conservative restoration that will protect the tooth over time. She explains her reasoning and the alternatives so you can guide your care.

What affects the cost?

The cost depends on the type of restoration, its material, and how many surfaces of the tooth are involved. Many dental plans cover fillings at a different level than onlays and crowns. Our team explains your coverage and expected cost before you commit to treatment.