Definition : Small instruments designed to be held and revolved by a rotary device to excavate objects, tissues, or other anatomic parts, usually by creating cylindrical holes. These instruments typically consist of a cylindrical shank of steel or other hard metal with a uniform cross-section. They include a working end with cutting edges (e.g., twisted, helicoidally), and a notched or elongated proximal end to fit into the rotary device (e.g., a handpiece, hand drill, drilling machine). Some drill bits are cannulated to allow their use over a guide wire. Dedicated drill bits are used in a variety of surgical (e.g., orthopedic, otolaryngology), dental, and postmortem procedures.
Entry Terms : "Twist Drills"
UMDC code : 23840