A dental drill or dentist's drill is a small, high-speed drill used during dental procedures, usually to remove decay and shape tooth structure prior to the insertion of a filling or crown. A dental drill may also be used in the cleaning and shaping of root canals during endodontic treatment, or to remove old or temporary fillings or crowns prior to the insertion of new or permanent restorations. The term "dental drill" is considered the more colloquial form of the term "dental handpiece," although it can also be construed as to include the power source for one or more handpieces, a "dental engine." "Handpiece" and "engine" are more generic and euphemistic terms for generic dental tools.