Ethylene Oxide Sterilization

Figure 10-12.—Dry heat sterilizer. Advantages to chemical vapor sterilization are as follows: No corrosion, rusting, and dulling of instruments since water content is only 15 percent (if instruments are dry when placed in chamber). Prevents destruction of dental items, such as endodontic files, orthodontic pliers, wires and bands, burs, and carbon steel instruments. Instruments are dry at the end of the cycle. The major disadvantage of this sterilization method is the requirement for adequate ventilation. Chemical vapors, particularly formaldehyde, can be released when the chamber door is opened, leaving a temporary but unpleasant odor in the area. Chemical vapor sterilization is not routinely used in Navy dentistry. Consult the manufacturer’s instructions for specific details on operation and required user maintenance. Ethylene Oxide Sterilization Ethylene oxide (ETO) gas uses relatively low temperatures for sterilization. Using a heated unit, sterilization can be achieved in 2-3 hours at 120°F. However, a lengthy aeration time must follow each cycle. Materials such as suction tubing, handpieces, radiographic film holders, and prosthetic appliances may be sterilized without adverse effects. Follow the manufacturer’s instructions for safety precautions, operation, and maintenance. Because of the serious Occupation Safety Health Agency (OSHA) problems with ETO gas, COs of Naval Dental Clinics (NDCs) should not purchase new ETO equipment. Large naval hospitals with ETO capabilities in their CSR may use them to sterilize nonheat stable dental instruments and equipment. Liquid Chemical Sterilization The Food and Drug Administration (FDA) classifies chemical disinfectants that are sporicidal as disinfectants, the FDA classifies all sterilants. Since monitoring the liquid sterilization process is virtually impossible, treat these products as high-level disinfectants rather than sterilants. Be sure to follow the manufacturer’s directions exactly. Bead and Salt Sterilizers Use bead and salt sterilizers only during the endodontic procedure for sterilization of clean metallic instruments. Do not use them to sterilize instruments between patients. Clean contaminated instruments with an alcohol saturated gauze to remove blood and debris before inserting into the bead and salt 10-13