The BUC-1 and BUC-1A can be used for gross dentin removal, moving access line angles, cutting a groove in the mesial access wall to drop in to MB2 canals, and for unroofing pulp chambers. Helpful in finding reclusive MB2s.
The BUC-2, with its disk-like radiused tip, can be used to plane attached pulp stones from the pulp chamber floor. In molars, it can be used to horizontally smooth the pulp chamber floor to get to the darker-colored dentin. Can be used for corners of molar access prep and bicuspid access prep.
The BUC-3 and BUC-3A are extremely active instruments with sharp tips. They are used for chasing canals halfway up a root or for digging around a post or carrier-based obturator to remove it. The water port is placed near the cutting surface of the tip. Use only at lowest power level.