Fracture at the Margins of Amalgam as Predicted by Creep, Zinc Content, and Gamma-2 Content

Fracture at the margins of amalgams as predicted by an equation suggested by Mahler using creep, zinc content, and gamma-2 content was tested on the three-year clinical results of 12 alloys. The results tend to agree with Mahler's results when gamma-2 and non-gamma-2 alloys are used in the same equation. This appears, however, to be an effect of combining two distinctly different types of alloys. It is suggested that, when non-gamma-2, low creep alloys are evaluated, the equation suggested by Mahler would be inappropriate. In addition, for non-gamma-2 alloys, the prediction using creep values does not appear to be appropriate.