Dental Health Topics

Inlay - Metallic, One Surface - Dental Procedure Code Description

An inlay is a form of dental restoration used to repair a decayed, chipped, cracked, or otherwise damaged tooth. In contrast to an onlay, which is used to correct damage extending to a cusp (the raised points on the biting surface), an inlay is used to repair only that portion of the tooth between these cusps.


Generally speaking, there are two different types of dental restorations: direct and indirect. For example, a filling is a type of direct restoration, because the material used to repair the tooth undergoes its hardening process while in direct contact with the tooth and inside the mouth. 


Unlike a filling, where a malleable material is placed into the tooth, and allowed to harden, an inlay is an already hardened material (like a crown) that is joined to the tooth by bonding or cement. Because the material used to repair the tooth is created outside the mouth, either in a lab by a dental technician, or via a computer-controlled milling machine, the process is referred to as an indirect restoration.

In all, there are five surfaces of the tooth eligible for restoration: the distal, occlusal, buccal, mesial, and lingual/palatal surfaces. With this dental procedure code, an inlay is made from any range of metals including: gold, silver and palladium, and placed on one of those surfaces.

To prepare for a single surface inlay, a dentist will first remove any decayed or weakened areas of the tooth. Then, depending on the process used by your dentist, either a physical impression of the tooth will be made, or 3D imaging will be used to render a digital impression. Next, you may be fitted with a temporary inlay until the custom version is completed, or if your inlay can be fabricated on-site your dentist will proceed with the installation.


Once the inlay has been prepared and is ready for installation, it will be laid into the excavated area of the tooth and bonded or cemented (luted) in place.

To look up and find more CDT dental codes from the American Dental Association, please visit our complete Dental Procedure Code Library.