The bonding of glass-ionomer cements to dental amalgam

Clinicians are frequently confronted with the problem of ditched amalgam restorations. Materials which develop strong bonds to amalgam and tooth substance appear to be suitable for repair of such restorations and eliminate the need for complete replacement. This study evaluated the bond strengths of three glass-ionomer cements to amalgam made from conventional and high copper alloys. It was found that the bond strength values to amalgam were comparable with those to enamel and significantly higher than those to dentine. All bonds to the high copper amalgam failed in a cohesive mode; for the conventional amalgam, failure was either of the adhesive or cohesive type.