Preliminary study of the forces developed by practitioners during amalgam condensation

The aim of this preliminary study was to analyze, in vitro, the forces deve loped by practitioners during amalgam condensation. Standardized Class ii c avities were drilled into 40 freshly extracted teeth. The forces exerted du ring condensation were then measured by means of a new device, the Endograp he, and plotted online or offline as a function of time on Endogrammes. The work techniques of the different practitioners revealed similarities. The mean values of the vertical forces (+/- SEM) were: 15 +/- 2 N for manual co mpaction of capsule amalgam; 8 +/- 3 N for manual compaction of amalgam wit h a higher mercury-to-alloy ratio; 6 +/- 4 N for mechanical compaction of e ncapsulated amalgam; and 4 +/- 2 N for mechanical compaction of the modiffe d amalgam. For the horizontal components, the forces were, respectively 5 /- 2 N, 0.1 +/- 0.05 N,3 +/- 1 N,and 0.7 +/- 0,2 N. The mean values of cond ensation time were 20 +/- 15 s for each incremental application, with a gre at variation in durations between the beginning and end of condensation. By visually depicting forces as a function of time the Endographe can be used to analyze the process of amalgam insertion and condensation. Future resea rch will study the relationship between the forces developed during condens ation and the adaptation of the amalgam to the wails of the cavity.