Fracture resistance of premolars with MOD amalgam restorations lined with Amalgambond

A comparison was made of the fracture resistance of premolar teeth with mesial-occlusal-distal (MOD) amalgam preparations lined with either a resin containing 4-META (Amalgambond) or copal varnish (Plastodent) and restored with a spherical alloy (Tytin). Restored teeth were aged for 7 or 67 days at 37 degrees C in 100% humidity and thermocycled between 5 and 55 degrees C for 3500 cycles. There was no significant difference in the mean fracture resistance between teeth lined with Amalgambond and teeth lined with Plastodent under any of the test conditions. SEM analysis of thermocycled specimens showed no evidence of maintained adhesion between the Amalgambond and amalgam.