Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER III. Instrument Nomenclature. A dental instrument is an appliance, or tool by means ol which a dentist performs dental operations. It is quite essential that we learn the names and uses of the instruments most in use if we are to understand the teaching of operative procedures. Instruments are named according to the purpose for which they are intended, where and how used, by describing their working points and the shape of their shank. An order name describes that for which an instrument is used, as for example, excavator, clamps, mallet, pluggers, burnishers, etc. A sub-order name describes where or how an instrument of a given order is used and is made by inserting a prefix before the order name. Examples, hand pluggers push or pull sealers, etc. A class name describes the working point of an instrument. Examples, serrated plugger, ball burnisher, chisel, hatchet, etc. A sub-class name describes the shape of the shank, and is made by prefixing this description to the class or order name or to both combined. Examples, bayonet plugger, bin-angle chisel, mon-anglc hatchet excavator, etc. Rights and lefts are made as further divisions of many of the sub-classes of instruments and this division is especially advantageous in the spoons, bin-angle, contra-angle hatchets and marginal trimmers as it enables the user to do the work by a movement of the instrument from right to left or left to right, respectively. An excavator is that order of hand instrument used in the removal of tooth substance preparatory to the making of a filling. A chisel is that class of excavator which has the cutting edge placed at right angles to the shaft, is sharpened by grinding on one side only and is used by a pushing force applied in the direction of the long axis of t...