A filling is a direct dental restoration used to repair decayed, chipped, cracked or otherwise damaged teeth.
It is called a 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.
Other procedures, such as inlays and onlays, are considered to be indirect restorations because the material used to repair the tooth is created outside the mouth. The material is created either in a lab by a dental technician, or via a computer-controlled milling machine.
In all, there are five surfaces of the tooth where a filling can be placed: the distal, occlusal, buccal, mesial, and lingual surfaces.
Additionally, teeth are segmented into two major categories: anterior and posterior. Anterior means teeth in the front of your mouth—up to and including your incisors. The remaining teeth fall under the category of posterior, which means closer to the rear.
With this dental procedure code, a filling made from a mixed metal alloy of mercury, silver, tin, copper, and other metals, is used to repair damage on four surfaces of a posterior tooth.
At times, this procedure can also be done on an anterior tooth if the surface is not readily visible within the smile-zone.
A four-surface silver filling is typically undertaken when cavities are found on what is referred to as the interproximal surface of the tooth. Simply put, these are the surfaces that butt up against the surface of another tooth. Access is gained to these areas by drilling through the biting surface of the adjacent tooth.
Amalgam is durable, costs less than some other restoratives, and is long-lasting. It’s also easy to place and hardens quickly, making it a good solution for filling large cavities that form deep in the tooth.
Prior to a four-surface amalgam filling, a dentist will first remove any decayed or weakened areas of the tooth, and then use a variety of instruments to prepare the tooth for the filling material.
Depending on the situation and your dentist’s preferences, an amalgam filling may be secured with cement. However, the most common practice is furthering excavation of a recessed ridge cut beneath the remaining healthy portion of the tooth's biting surface. These relief cuts prevent the amalgam from falling out, and increase its retention and resistance to slipping. One such cut is a dovetail relief used similarly in woodworking.
Once the filling is layered in place, your bite will be checked to ensure all surfaces meet naturally with the new filling. Typically, after at least 24 hours, your dentist will then re-examine the filling, and shape and polish it to follow the natural contour of the tooth.
To look up and find more CDT dental codes from the American Dental Association, please visit our complete Dental Procedure Code Library.