Techniques for Sharpening Instruments
Sharp instruments are essential to effective and efficient patient care. They increase tactile sensitivity, lessen the pressure needed to scale, and reduce the chances of burnishing calculus deposits.
The objective of sharpening is to produce a sharp cutting edge without changing the original design of the instrument. The cutting edge of the instrument is the junction of the face of the blade with the lateral surface.
Sharpness can be evaluated both visually and tactilely.
Dull instruments have a rounded cutting edge that reflects light back at you; this appears as a white line on the cutting edge of the instrument.
You can test the sharpness with light pressure against your thumbnail or use an autoclavable plastic stick. If the instrument grabs the surface, it is sharp.
There are several sharpening techniques and methods used that will produce a sharp instrument with out altering its original design. We will demonstrate on an unmounted flat stone with both curets and sickles.
Principals of sharpening:
• Choose a stone appropriate for the instrument that needs to be sharpened.
• Use a sterilized stone if you are sharpening during patient treatment.
• Use the proper angle between the stone and the blade of the instrument.
• Maintain a firm grasp of both the stone and the instrument keeping the entire surface of the blade even with the stone to produce a proper cutting edge.
• Use up and down strokes finishing with a down stroke toward the cutting edge.
• The angle between the face of the blade and the lateral surface of any curet is 70-80 degrees for the most effective calculus removal.
How to Sharpen your instruments:
Sharpening Universal Curets:
• Lay the lateral surface of the curet on the stone at a 90 degree angle.
• Open the angle by rotating the instrument 10-20 degrees, laterally.
The angle betwe•en the stone and the face of the blade is now 100-110 degrees and perpendicular to the floor.
• Start at the shank of the cutting edge and work toward the toe, using a consistent light pressure in an up and down motion and maintaining the correct angle, a metal sludge should appear on the face of the blade.
• Test sharpness on a plastic stick. Once that end is sharp, the opposite can be sharpened the same way.
Sharpening Gracey Curets:
• Unlike a universal curet which has a straight cutting edge, Gracey curets are curved when viewed above the face of the blade.
• Use the same technique as above with a few modifications.
• Hold the face of the blade parallel to the floor; the Gracey curet has an offset blade.
• The same angles apply, as above, now turn the instrument from shank to toe as you sharpen with up and down strokes, as not to flatten the blade and to keep the original rounded curvature of the blade.
• Some sickles have entirely flat later surfaces the angle between the face of the blade and the stone will automatically be 100-110 degrees.
• Sharpen with short up-down stokes using a consistent light pressure keeping the stone in contact with the blade.
• Look for the sludge check the sharpness.
There are many different ways to sharpen instruments use what works for you. Sharp instrumentsare not only a part of patient treatment they are a very important part of ergonomics and longevity in your career.
For video using Sidekick Sharpener go to: http://www.friendsofhu-friedy.com/SidekickSharpener.asp