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February 2024
Keep Your Skills Sharp
Maintaining dental instruments is critical to performing proper dental procedures. Sharp scalers and curettes are much more effective at cleaning teeth than dull instruments. Brook A. Niemiec, DVM, DAVCD, DEVDC, talks about taking the best care of your dental hand instruments.
Care and Sharpening of Dental Hand Instruments
How often do you sharpen your dental instruments? Daily, weekly, monthly, annually . . . NEVER? You should be sharpening your instruments at least weekly. Why, you ask? Because it has been shown that periodontal hand instruments can dull after only 15 to 45 scaling strokes. This means, if you have not sharpened this week, (or today) your instruments are likely dull. Further, bringing very dull instruments back to being sharp is difficult to impossible with standard hand sharpening techniques.
Maintaining dental instruments is critical to performing proper dental procedures. Sharp scalers and curettes are much more effective at cleaning teeth than dull instruments. In fact, dull instruments are a leading cause of “burnished” calculus. This means that the calculus is smoothed, but not removed, leading to perceived cleanliness, but ultimate treatment failure. Not only are sharp instruments more effective, but they are also more efficient. This means that the teeth will be cleaned faster, thus decreasing procedure time. This in turn decreases the length of anesthesia, which benefits the patient.
The improved efficiency allows the veterinarian or technician to move on to other tasks faster, which is good for the practice. Finally, since the teeth are cleaned faster and with less effort, it will help decrease repetitive motion injuries and improve ergonomics. This is critical for the long-term health of your staff as ergonomic issues have been shown to be almost ubiquitous in human dentistry.
Keeping your dental hand instruments sharp is beneficial to your patients, staff, and bottom line.
Thus, keeping your dental hand instruments sharp is beneficial to your patients, staff, and bottom line. Thus, it is an ethically sound practice. All of us should strive to keep our instruments sharp.
How Do I Know My Instruments Are Sharp?
There are two main ways to determine if your instruments need to be sharpened. This can be done visually. First, shine a bright light on the cutting edge of the instrument. The best way to do this is to utilize surgical loupes, but any bright light can work. If the instrument reflects light, the cutting edge is dull (Figure 1). Another technique is to use a plastic testing stick to check for sharpness. Place the instrument on the stick how it would be positioned on the tooth. If the instrument does not easily remove some of the stick, it requires sharpening (Figure 2).
Figure 1: Visual inspection of blade to determine if sharpening is needed. 1a) Light is reflected from the blade indicating it is dull. 1b) No light is reflected, indicating a sharp instrument.
Figure 2: Using a plastic testing stick to determine sharpness. If the instrument is sharp, a layer of the block should be removed easily. If none comes off the instrument is dull.
Hand Sharpening
This is the cheapest and by far most common technique for instrument sharpening. It is not difficult to learn/perform, but it is very technique sensitive. All that is required for this procedure is a sharpening stone and oil. The most common stone recommended for sharpening veterinary dental hand instruments is an Arkansas stone. It has shown to be quite effective at creating a sharp, consistent edge. India as well as numerous ceramic and artificial “stones” for sharpening may be as (or more) effective, however, they are not as commonly used. An Arkansas stone should always be used with sharpening oil. Both products are inexpensive and can be purchased from any dental or veterinary distributor, or as a sharpening kit (Figure 3).
Figure 3: All the equipment needed for hand sharpening, VDS sharpening kit.
Technique
Whether the stone or instrument is moved during sharpening is controversial with both techniques being advocated. Either one provides a sharp surface, however, moving the stone is more commonly recommended and thus will be presented here.
Apply a small amount of sharpening oil on the area of the stone you will use (Figure 4).
Figure 4: Place a small amount of oil on the stone.
Hold the instrument in your dominant hand (the one you write with) and the stone in the other.
Place the instrument on the stone as it would be used for scaling. This means that the shank (or terminal end of the instrument) is parallel to the stone (Figure 5).
Figure 5: Place the instrument (in this case a universal scaler) on the instrument how it would be used on the tooth. This means the shank is parallel to the stone.
Rotate the instrument 20 degrees from this angle to create the desired edge (20 degrees is approximately the angle your fingers make with a “peace sign;” Figure 6).
Figure 6: Bring the instrument 20 degrees off of parallel and move the stone back and forth with more force on the “down” stroke.
Adjust your technique based on the shape of the instrument:
When sharpening scalers or curettes with a flat face, keep the instrument in the same position throughout the sharpening process.
When sharpening curved instruments (most curettes), start with the “heel” of the instrument against the stone and slowly rotate the instrument during sharpening to ensure that the whole blade is sharpened (Figure 7a–c).
Figure 7: When sharpening a curved curette, the entire curve needs to be sharpened.
7a) Start on the heel
7b) Progress to mid blade
7c) End on the toe
Keep the instrument still and move the stone in short, firm up and down motions. Place more force on the down stroke (Figure 6).
Always end on the “down” stroke to avoid burring the instrument (Figure 8).
Figure 8: End on the “pull” stroke to avoid burring the instrument.
Occasionally check for sharpness visually or with an acrylic testing stick (Figures 1 and 2).
After you have ensured that your instruments are sharp, they should be cleaned, wrapped, and autoclaved. Ideally, they are checked visually just prior to use.
As previously stated, bringing a very dull instrument back to a sharp edge and useful condition is very hard to impossible. If no sharpening has been performed for months to years, it may be best to purchase new instruments and then make a commitment to maintenance. Other options for very dull instruments include a mechanized sharpening system or sending out to a professional sharpening service. There are human companies who may provide this service as well as at least two veterinary offerings.
Honing Device and Instructions
Larger practices, or those who perform a significant number of dental procedures, may consider investing in a “honing” device. This is a mechanical sharpener with preset angles and various stones/polishers to quickly bring dull instruments back to a sharp edge. These are relatively inexpensive and easy to use. While this is certainly more of an investment than a sharpening stone and oil, it does make sharpening more efficient and potentially superior to hand sharpening. While there are several units available, the one typically used in veterinary dentistry is the RxHoning device. While it has attachments for luxating elevators, it finds most of its use as a periodontal hand scaling device.
By using a rotating stone, it sharpens instruments in less time and requires less physical work by the operator. In addition, because it has a sharpening guide, it can provide superior results. However, they can be more aggressive and thus lead to more instrument structure loss, so they must be used carefully.
To use this device, you need to determine if your instrument is a universal or a “Gracey” curette. This information should be imprinted on the instrument. If not, you can tell by looking at the blade. Universal curettes have a 90-degree angulation and can thus be used on both sides, whereas the Gracey are angled to 70 degrees for better adaption to the tooth (Figure 5).
Then, using the guide on the machine, apply the instrument at the correct angle (U for universal and G for Gracey; Figure 9a and b). Note that both sides of universal hand instruments are sharpened as opposed to the Gracey which only has one working edge.
Figure 9: Utilize the proper guide to sharpen curettes on a mechanical device. 9a) “G” for Gracey curettes. 9b) “U” for Universal curettes.
Using the foot pedal, control the speed of the rotating stone.
Continue the process until the instrument is sharp. As with hand sharpening above, you should check the instrument often during the sharpening process, as over sharpening is also detrimental.
The images and descriptions in this article should be sufficient for you to maintain your instruments. If you desire further instruction, most hands-on periodontal laboratories will teach these techniques. In person and virtual video options are available through VDSpets.com.
Brook Niemiec, DVM, DADVC, is recognized internationally as one of the leading authorities in veterinary dentistry. He is a past president of the Academy of Veterinary Dentistry, as well as the American Veterinary Dental College delegate to the World Small Animal Veterinary Association. |
Photo credits: Brook A. Niemiec, DVM, DAVCD, DEVDC