A steel dental drill manufactured by the Dental Manufacturing Co, London. When a tooth develops a cavity, it is esential to remove the decayed tisue. In order to achieve this, dentists have used drills as part of their equipment since the early 18th century. Powered drills were developed in the 19th century, and the first electrically powered dentist's drill appeared in 1874. The development of high-powered drills in the 1950s greatly improved the effeciency in removing areas of tooth decay. Modern turbine powered drills rotate at speeds of 300,000 to 400,000 rpm.
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