The Low Down on Slow-Speed Handpiece Asepsis
Nancy Andrews, RDH, BS
Is your handpiece motor a “weak link” in office asepsis and efficiency? Dental Professionals who have lightweight, ergonomically designed models with swivel connectors may have only one handpiece, making it impossible to sterilize between each patient. They may even believe that heat sterilization is unnecessary or NOT recommended. In fact, there are three reasons why slow-speed handpieces should be sterilized after each use: 1) to follow CDC Infection Control Guidelines, 2) for optimal asepsis, and 3) for the best performance and life of the motors.
CDC Recommendations for Dental Handpieces and Other Devices Attached to Air and Waterlines:
- Clean and heat-sterilize handpieces and other intraoral instruments that can be removed from the air and waterlines of dental units between patients.
- Follow the manufacturer’s instructions for cleaning, lubrication, and sterilization of handpieces and other intraoral instruments that can be removed from the air and waterlines of dental units.
- Do not surface-disinfect; use liquid chemical sterilants or ethylene oxide on handpieces and other intraoral instruments that can be removed from the air and waterlines of dental units.1
Studies have shown that high-speed handpieces and prophy angles may retract patient materials, internally retain potentially infectious pathogens, and expel these contaminants to subsequent patients. Studies have not been conducted to demonstrate similar risk with internal contamination of slow-speed motors, however, restricted physical access limits their cleaning. For processing any dental device that can be removed from the dental unit air or water lines, neither surface disinfection nor immersion in chemical germicides is an acceptable method. In addition, ethylene oxide gas cannot adequately sterilize internal components of handpieces. Manufacturer’s instructions for cleaning, lubrication, and sterilization should be followed closely to ensure the effectiveness of the process and the longevity of handpieces.1
Since many dental hygienists have only one motor/handpiece, they may follow the long-established practice of leaving it attached to the tubing, surface disinfecting it between patients, and/or covering it with plastic barriers during use. The CDC Guidelines, however, recommend removing and sterilizing handpieces and following manufacturers’ directions.
Surface Disinfectants and Slow-Speed Handpieces
Most slow-speed handpieces are removable and can withstand sterilization conditions. While it is arguable that slow-speed handpieces do not enter the mouth and may not require heat sterilization after each use, each manufacturer strongly recommends that this be performed. If handpieces are not autoclaved, external cleaning disinfection with intermediate level disinfectants are the next choice, with or without use of barriers. Manufacturers all caution against long-term, repeated exposure to surface disinfectants, since the chemicals corrode and pit the external handpiece surface, can “gum up” and freeze gears and attachments, and cause handpieces to fail when allowed to penetrate seals and connections. Spray disinfectants can also fuse handpieces to hose attachments if they are not removed frequently. Each handpiece brand carries unique instructions, however, all models will last longer, perform better, and meet today’s standard of sterility if they are removed and heat sterilized rather than left on the tubing and covered, wiped, or sprayed with chemicals.
*OSAP member and consultant on infection control.
- Centers for Disease Control, Guidelines for Infection Control in Dental Health Care Settings –2003, 36-37, 56. www.cdc.gov/OralHealth/infectioncontrol/guidelines/index.htm.
- National Dental Handpiece Repair Association Guideline for Handpiece Maintenance. www.handpieceinfo.com Accessed 8-18-06.