PennWell Dental Community
Last time we discussed how the hardness of the dental instrument sharpener affects its performance. Now let’s discuss the grit. The coarser the grit, the faster the stone sharpens. The coarser the grit, the more imperfect the sharpened edge is, in other words, the rougher the edge. So, is there a happy medium? I think there is.
Most of us were taught to use a fine grit sharpening stone in order to end up with a fine edge. We would spend a great amount of time sharpening our instruments to achieve this “perfect edge”. The rational was that we needed a smooth edge in order to produce a smooth root surface. This is what we were taught, but no one, to my knowledge, proved that it was true. It was an assumption made that became universally accepted.
I agree that a rough cutting edge will most likely result in a slightly rougher root surface. However, I have many questions concerning the importance of this. First, how long does the cutting edge remain rough during use? My speculation is that, after a few strokes, the minor imperfections of the cutting edge caused by a coarser stone will be worn away.
Second, what is the clinical significance of a slightly rougher root surface? In other words, how much rougher does it need to be to be clinically significant? Logic tells me that a slightly rougher root surface is not clinically significant.
Third, under-sharpened instruments leave calculus, and even worse, burnish calculus making it undetectable. Those dull instruments require more force to remove deposits, increasing the danger of slipping. Because more force is needed, under-sharpened instruments increase patient discomfort.
I believe that a patient’s periodontal health is jeopardized when using an under-sharpened dental instrument more than it is when using sharp instruments that have minor edge imperfections.