While many instrument sharpening companies offer retipping services, it is not the ideal way to replace worn instruments. Safety and quality control are issues surrounding retipping. All manufacturers use proprietary raw materials and metals that may not be conducive to retipping by another manufacturer. Most instruments are made with a combination of carbon, chromium, nickel, and molybdenum. While the carbon, nickel, and molybdenum contribute to the hardness of the steel through a heat-treated process, the chromium provides the necessary corrosion resistance to withstand sterilization. Retipping by another company may not have the same proprietary raw materials, thereby weakening the overall instrument.
During the retipping process, high heat is needed to forcibly extract the working end, which breaks the chemical and mechanical seal created by the original manufacturer. A new tip is then pressed into the handle. This process may produce microcracks in the collar of the handle, weakening it, along with the potential to create microleakage of bacteria into the handle. When a new tip is forced into a weakened handle, further damage may result. The original dimensions at the collar may be altered, making it impossible to replicate the precision of the original instrument. Small gaps can occur at this critical junction.
All instruments should be consistent in balance, shape, size, and shank design. In a balanced instrument, the working ends are centered on a straight line running through the handle. Proper instrument balance ensures each instrument feels similar for consistency in pressure when applying the working stroke. Retipping can alter that balance, causing strain on the hand. Instrument manufacturers create cutting edges, working-end angulations, and shank designs that are consistent and reproducible. Retipping often alters the angle of the working end and/or shank design, making scaling strokes less effective and uncomfortable to perform. Once the instrument is altered, it is considered remanufactured and the original warranty is void.
The United States Food and Drug Administration (FDA) monitors dental instruments under the category of medical devices. According to FDA regulations, all retipped instruments should be identified as "retipped" or "refurbished," so clinicians understand that instruments have been altered and may be compromised in performance. The guidelines also indicate the original manufacturer is absolved from all liability.
So what are the alternatives to retipping? Sharpening on a regular basis is critical to maintaining the sharp edge and the shape of the working end. Appropriate technique is important and clinicians should take great care in maintaining both shape and edge. Look for instrument warranties, trade-in opportunities, and "no sharpening" or "less sharpening" technology. Because the life expectancy of an instrument is influenced by a variety of factors, the timing of replacement cannot be reasonably determined. Instruments are not meant to last a lifetime and it's important to create a plan for replacing instruments over time.