Micro-Trephine Bur Tip and Katana-H when they become

and Katana-H when they become chipped or dull

The Micro-trephine bur is used at 600 rpm in a counter-clockwise direction to encourage separated files to unthread from the canal as the trough is cut

The ultrasonic preparation continues until the movement of the broken instrument is confirmed under the 4 magnification

ED89(TFRK-Katana H) tips usually cut only a quarter slot of the circle

creating a small space adjacent to the fractured file edge

Micro-Trephine Bur Tip and Katana-H when they becomeTiny cylinder with cutting blades on its tip to create a trough 1 mm deep around the coronal portion of the separated file. The Micro trephine bur is used at 600 rpm in a counter clockwise direction to encourage separated files to unthread from the canal as the trough is cut.