Saiji Shimoe

Effect of noble metal conditioners on bonding between prosthetic composite material and silver-palladium-copper-gold alloy.

STATEMENT OF PROBLEM Mechanical retentive devices and the application of complicated surface preparation have been indispensable for bonding composite material to the metal substructure of restorations. PURPOSE This study evaluated the priming effects of 4 metal conditioners on bonding between a prosthetic veneering material and a silver-palladium-based casting alloy. MATERIAL AND METHODS Four primers designed for conditioning noble metal alloys (Alloy Primer, Metaltite, Metal Primer II, and V-Primer) were assessed (all materials contain organic sulfur compounds). Cast disk specimens made of silver-palladium-copper-gold alloy (Castwell M.C.12) were primed with 1 of the 4 primers, and bonded with a light-activated prosthetic composite material (Axis). Shear testing was performed before and after thermocycling for evaluation of bond durability. RESULTS All primed groups showed improved 24-hour bond strengths compared with the unprimed group. After thermocycling, 3 groups primed with the Metal Primer II, Alloy Primer, and Metaltite agents exhibited the highest bond strength. CONCLUSION Use of 1-liquid metal conditioners containing sulfur compounds was a simple and useful method for improving bonding between the alloy and the composite material tested.