Bengtsson U

“Conventional amalgams are regarded as less favorable because of their proneness to corrosion and mechanical weakness. An invention by a Canadian scientist in 1963 marked the introduction of the modern non-gamma-two amalgams said to overcome these drawbacks. Now some thirty years later it is obvious that they also exhibit a drastic reduction in stability. The emission of mercury vapor – see Figure 2 – is drastically increased and is combined with the formation of deposits on the surface after abrasion, see picture above. No scientific article has been accepted for publication on this striking and highly visual phenomenon of instability – just a few IADR Abstracts have been dealing with it.

These new amalgams were marketed for a long time in opposition to the composition-standard in force. When they became dominating on the market the standard was rewritten allowing the use of non-gamma-two amalgams that had already been sold for more than a decade. Standards for testing the stability – emissions of toxic substances – of amalgams are non-existing. One reason for the increased strength of modern amalgams could be that they contain bronze.”