Dr. Harold Loe, the Director of the National Institute of Dental Research (NIDR) stated in the September, 1993 edition of "Dental Products Report":

"That first filling is a critical step in the life of a tooth. (1)

Using amalgam for the first filling requires removing a lot of the tooth substance, not only diseased tooth substance but healthy tooth substance as well. (2 & 3)     

So, in making the undercut you sacrifice a lot, and this results in a weakened tooth. (4)

The next thing you know the tooth breaks off, and you need a crown. (5)

Then you need to repair the crown...and so it continues to the stage where there is no more to repair and you pull the tooth.” (6)

High copper amalgams release mercury at a much higher rate than the older non-copper amalgams.

The rate of expansion and contraction is not the same as the tooth. Also the metals in a mercury amalgam undergo considerable corrosion which is accompanied by considerable expansion. The net result being the creation of stress fractures of the cusps. This will weaken the tooth substantially as large parts literally will break off. Micro fractures of tooth structure will in some cases also cause considerable pain.

To suggest that the alternatives to amalgam do not last as long is to ignore the wealth of research published in the dental journals which indicate the exact opposite.