According to its name, this tool is supposed to help orthodontists assess the amount of torsional play in various combinations of bracket slots and archwires.

It is absolutely free to use. However, it takes the liberty of gathering anonymous usage statistics.

Usage is quite simple. You set slot and archwire dimensions and click on the ,,show result" button to display the amount of (theoretical) torque loss. The amount of archwire bevel is not usually specified by manufacturers. The preset value of 2 is a rough estimation based on literature. As for slot edge bevel, this parameter is of interest when an archwire protrudes over the slot edge.