Effectiveness of two types of sterilizers on the contents of sharps containers.
The purpose of this study was to evaluate the killing effect that a gravity steam autoclave (GSA), a high-vacuum steam sterilizer (HVA) or an unsaturated chemical vapor sterilizer (UCV) had on endospores present on strips or applied to dental needles within three sizes of sharps containers. Commercial spore strips containing 1.7 x 10(5) Bacillus stearothermophilus endospores were used, while the needles were soiled with an equal number of spores or with spores mixed with blood. Needles were tested capped and uncapped. Initial operating conditions were for the: (1) GSA were 129 kPa at 124 degrees C for 30 minutes; (2) HVA were 214 kPa at 131 degrees C for 10 minutes and (3) UCV, 172 kPa at 134 degrees C for 20 minutes. Strips and needles were placed within 3/4 filled containers. Fill materials consisted of needles, syringes, plastic sheaths and scalpel blades. Containers were processed upward or on their sides. Twenty-five strips or needles comprised a test group for each operational parameter. Processed strips and needles were aerobically cultured at 56 degrees C for 7 days. If sterilization was not accomplished after the initial period, additional exposure time was added. Results included: (1) soiled needles are more difficult than strips to sterilize; (2) capping or the presence of blood did not affect sterilization efficiency; (3) container positioning was important only for the smallest container; (4) additional exposure time was usually required when sterilizing soiled needles; (5) the HVA killed all spore challenges in a single sterilization cycle and (6) GSA and UCV were approximately equal in sterilization efficiency.(ABSTRACT TRUNCATED AT 250 WORDS)
Palenik
C J
CJ
Department of Oral Biology, Indiana University School of Dentistry, Indianapolis 46202-5211.
Golden
L C
LC
D000766:Anesthesia, Dental / Q000295:instrumentation; D015169:Colony Count, Microbial; D003762:Dental Instruments; D001411:Geobacillus stearothermophilus; D009339:Needles; D013171:Spores, Bacterial; D013227:Steam; D013242:Sterilization / Q000295:instrumentation* / Q000379:methods; D014618:Vacuum
D013227:Steam