The AAC process consisted of activating the silver powder by submerging it in a 10% volume fraction HBF4 (dilution from a 48% mass fraction of HBF4) solution in a glass beaker, and stirring with a slowly rotating overhead stirring paddle for 1 min. The powder particles were allowed to settle for several minutes, and the acid was decanted leaving behind the settled powder as a wet slurry. In most instances, the slurry was rinsed in a second more dilute solution, 2% volume fraction HBF4. Compaction of the silver slurry was performed manually with hand dental instruments in order to simulate actual dental procedures in the low pressure(