Inlays and onlays are a type of indirect restoration, where your dentist fabricates the restoration outside of your mouth and cements it into place. A direct restoration, most commonly fillings, are placed immediately into a prepared cavity in a single visit.
Inlays and onlays are used in molars or premolars, when the tooth has experienced too much damage to support a basic filling, but not so much damage that a crown is necessary. They can be made of gold, metal alloys, ceramics, or composites. An inlay is used when the cavity rests between the cusps, whereas an onlay covers one or more cusps, as well as the area in between. A crown replaces the entire outside area of the tooth above the gum line.
Indirect fillings generally require two or more visits. During the first visit, your dentist prepares the tooth and makes an impression of the area to be restored. Your dentist then places a temporary covering over the prepared tooth. The impression is sent to a dental laboratory, which creates the dental restoration. At the next appointment, we cement the restoration into the prepared cavity and adjust it as needed.