More and more patients are interested in inlay and onlay fillings. However, inlays, onlays and overlays are relatively expensive, sometimes as expensive as porcelain crowns. So many patients are unsure which treatment makes more sense. Learn more about inlay, onlay and overlay fillings in the article below.
1. What are inlay, onlay and overlay fillings?
Inlays, onlays and overlays are fillings that the dentist has shaped in a lab from porcelain, composite, GIC or other materials, and then bonds to the tooth.
Inlays, onlays and overlays are suitable when a tooth is decayed or so badly damaged that a regular direct filling is not enough, but the damage is not severe enough to need a porcelain crown.
1.1 Inlay fillings
Inlay fillings are used when the cavity or damaged area is in the middle of the tooth and has not spread to the cusps.
Inlays are custom made to fit each patient and are close to the color of the natural tooth. So it is hard to see the difference with the naked eye.
1.2 Onlay fillings
Compared with inlays, onlays suit teeth that need a larger area restored, including the middle of the tooth and the tips of the cusps.
Onlays are sometimes called partial porcelain crowns, because the finished filling looks like a small part of a porcelain crown.
1.3 Overlay fillings
Overlays are usually used for teeth that are very badly damaged or decayed. The damage affects more than 2 cusps or the entire biting surface (as if half of the crown were missing).
Patients who are new to this often confuse overlays with porcelain crowns, because overall the area restored by the two techniques is fairly similar.
The difference between an overlay and a porcelain crown is how much of the tooth is ground down. An overlay does not require grinding down almost the whole tooth like a porcelain crown does. Instead, the dentist only removes a minimal amount of enamel and makes sure the filling bonds as firmly as possible.
Key advantages of inlay and onlay fillings
Not invasive to the natural tooth
Very little of the tooth is ground down for inlay and onlay fillings, so the treatment is completely non-invasive to the natural tooth and protects it as much as possible.
Natural looking
The appearance of the tooth is preserved, because the filling has the same color as the natural tooth, thanks to CAD/CAM technology: computer-aided design and manufacturing of the filling.
Easy to clean
The filling is shaped to fit each patient's tooth and avoids grooves where food easily gets stuck, so you can keep your teeth clean easily.
Strong and long lasting
Thanks to CAD/CAM technology, the filling bonds well and is extremely durable, especially when used for decayed teeth. These fillings last up to 15 to 20 years on average. You also do not need many follow-up visits, so it does not take much of your time.
Inlays and onlays are less likely to come loose or fall out than composite fillings.
Saves time and money
Because it is done once and lasts a long time, an inlay or onlay saves you a lot of time and money. And compared with porcelain crowns, it costs less while the quality is just as good.