Effect of two metal primers on adhesive bonding with type IV gold alloys.

Bond strengths of an adhesive resin bonded to two types of gold alloys were investigated in vitro with two different metal primers. Disk specimens were cast in a type IV gold alloy designed for resin-bonded restorations and in a low-temperature age-hardenable gold alloy. The specimens were primed with either a vinyl-thiol primer or a thiophosphate primer, then bonded with an adhesive resin initiated with tri-n-butyl borane derivative. Both primers effectively enhanced bond between gold alloys and the adhesive. The use of metal primers in conjunction with type IV gold alloys is useful for resin-bonded fixed partial dentures.