1-5.
MAINTENANCE OF CUTTING INSTRUMENTS
Restorative procedures cannot be done adequately without proper maintenance of
equipment. Sharp cutting instruments are particularly important and present a continual
maintenance problem for the dental specialist. Regardless of what type of cutting
procedure (oral hygiene, restorative, or surgical) is to take place, it is very important to
have sharp instruments. The dental officer can do a better and more efficient job if he
has sharp instruments to work with. You, as a dental specialist, will be responsible for
sharpening these instruments. There are three very important reasons for having sharp
instruments. A sharp instrument decreases the chance of traumatizing the patient's soft
tissue, or of operator fatigue, and, therefore, greatly increases efficiency.
a. Techniques for Sharpening Instruments.
(1) The fixed-stone technique. The fixed-stone technique is the first of three
techniques for sharpening instruments that we will consider. Fixed stones are unmounted
stones. There are two types--hand stones with rounded edges, in cylindrical or
rectangular shapes, and flat stones, rectangular in shape, which may be smooth without
grooves or have one surfaced grooved lengthwise (see figure 1-2). Equipment for the
fixed-stone technique consists of either a CarborundumTM stone or an Arkansas stone, a
lubricant, two-inch by two-inch gauze, and, of course, the instrument to be sharpened.
The CarborundumTM stone is a soft (artificial) stone that has a coarse grit, thereby limiting
it to gross sharpening only. CarborundumTM stones are made in both flat and thin taper
shapes. The Arkansas stone is a natural stone and comes in varying hardness. It is a
fine stone for obtaining a finished edge. Black Hard is the hardest Arkansas stone. Hard
is the next hardest, followed by Soft (good for hunting knives, and so forth) and Washita (most
rapid cutting), which has a fine grit, thereby producing a fine edge. Arkansas stones
come in varying shapes: flat (grooved on one side), flat on both sides (without grooves),
cylindrical, and tapered. The fixed-stone technique has one primary advantage. Use of
the fixed stone will remove only minimal metal. However, the technique is messy because of
the oil that is required as a lubricant. The oil prevents metal particles from adhering to the
stone, reduces friction, thus reducing heat, and aids in producing a fine edge on the
instrument.
Figure 1-2. Flat sharpening stones.
MD0503
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