Previous studies have indicated that adhesive liners can affect the mechanical properties of set amalgam and, therefore, may become incorporated within the amalgam. The purpose of this in vitro study was to determine the distribution of two adhesive liners within standardized Class I amalgam restorations. Cavity preparations were restored with dental amalgam or with dental amalgam and either of two adhesive liners. Thin sections were cut from the restored teeth in various planes and examined radiographically and with a reflecting microscioe. Radiographs were digitized and computer enhanced for improved observation. Amalgam restorations placed with adhesive liner had greater amounts of nonadmalgam substance t han did the nonadhesive liner restorations. Both Amalgambond Plus and Resinomer used with All-Bond II were capable of becoming incorporated within the body of a Class I restoration placed with a standard restorative amalgam bonding technique.