A dental drill or handpiece is a hand-held, mechanical instrument used to perform a variety of common dental procedures, including removing decay, polishing fillings, performing cosmetic dentistry, and altering prostheses.

The handpiece itself consists of internal mechanical components which initiate a rotational force and provide power to the cutting instrument, usually a dental burr. The type of apparatus used clinically will vary depending on the required function dictated by the dental procedure.

American dentist George F. Green invented pneumatic dental drill in 1868. It was powered with pedal-operated bellows. Pedal-powered burr drill appeared in 1871 and was an invention by James B. Morrison. George F. Green also invented and patented the first electric dental drill in 1875 which revolutionized dentistry.

Electric dental drills were improved in time and by 1914 they could reach speeds of up to 3000 rpm. John Patrick Walsh, with members of the staff of the Dominion Physical Laboratory (DPL) Wellington, New Zealand, invented predecessor of a modern air turbine hand piece dental drill in 1949. A second wave of rapid development occurred in the 1950s and 60s, including the development of the air turbine drill.

According to Wikipedia