Dr JP Steyn is a prosthodontist specializing in the cosmetic restoration and replacement of teeth.
What are Inlays and Onlays
Also known as indirect fillings, dental inlays and onlays fit in somewhere between crowns and fillings. They are used on teeth at the back of the mouth on moderately structurally damaged teeth; more seriously damaged will probably be repaired using a crown. They are a conservative alternative to full crowns. They are stronger, fit better, and last longer than traditional fillings, and are also more aesthetically attractive.
Inlays and onlays are usually made from resin or porcelain, but can be made from gold. However porcelain and resin inlays and onlays are more appealing as they can be coloured to look natural. For this reason, they are used sometimes to replace unattractive fillings. Dental fillings are molded into place within the mouth during a dental visit, while inlays and onlays are produced in a dental lab before being fitted and bonded to the damaged tooth in a dental surgery.
The patient before treatment.
The patient after an unattractive filling has been replaced by a composite inlay.
What Is the Difference between an Inlay and an Onlay?
An inlay is placed inside the cusp, or the bumps of the teeth. This is a small area. Onlays are slightly larger and cover the whole chewing area, as well as replacing the cusp(s) of the teeth. Onlays are more similar to crowns.
How long does it take?
Usually 2 appointments (of one to two hours each) are needed to complete the procedure. During the first appointment the tooth is prepared for the inlay/onlay. An impression is made of the tooth to be sent to the lab for the production of the inlay or onlay. A temporary sealant is then applied to the tooth.
The sealant is removed on the second appointment, and the inlay/onlay is fitted. If the fit is up to standard, it will be bonded to the tooth with strong resin and polished to a smooth finish.
Advantages of inlay/onlays
While fillings reduce the strength of a tooth, inlays/onlays are bonded to the tooth using high strength resins, and actually increase the strength of the tooth.
They can last between 10 -30 years.
Due to the fact the resin or porcelain can be coloured to match your natural teeth, they are more attractive and less noticeable than fillings.