Dental Fillings, Dental Restorations

The ADA divides dental restorations into two categories:  direct  and indirect.

“Direct restorations are fillings placed immediately into a prepared cavity in a single visit. They include dental amalgam, glass ionomers, resin ionomers and some resin composite fillings. The dentist prepares the tooth, places the filling and adjusts it during one appointment.

Indirect restorations generally require two or more visits. They include inlays, onlays, veneers, crowns and bridges fabricated with gold, base metal alloys, ceramics or composites. During the first visit, the dentist prepares the tooth and makes an impression of the area to be restored. The impression is sent to a dental laboratory, which creates the dental restoration. At the next appointment, the dentist cements the restoration into the prepared cavity and adjusts it as needed.”

(ADA – http://www.ada.org/public/topics/fillings.asp)