ABSTRACT
Objective To investigate whether ultrasonic coupling agent (UCA)can produce shielding or antago-nistic effect on iodine disinfectant for preoperative skin disinfection.Methods Shielding or antagonistic effect of UCA on iodine disinfectant were detected by laboratory carrier immersion killing test and on-the-spot skin disinfec-tion test.Results Antagonistic effect:after the mixing of iodophor with UCA,the average killing rate of iodophor containing available iodine 2 500mg/L and 625 mg/L to Staphylococcus aureus decreased from 100.00% to 99.67%-99.78% and 96.85 % - 98.25 %,respectively;the average killing rate to Escherichia coli decreased from 100.00% to 99.71 %-99.82% and 95 .93 %-98.56%,respectively.Shielding effect:after smearing with UCA, the average killing rate of iodophor and iodine tincture + alcohol to Escherichia coli decreased from 100.00% to 30.76% and 100.00% to 94.48%,respectively;the average killing rate to Staphylococcus aureus decreased from 99.99% to 55 .55 % and 100.00% to 98.22%,respectively.On-the-spot skin disinfection test:the killing rate of io-dophor and iodine tincture +alcohol to natural bacteria on skin surface were both 99.99%,after skin was smeared with UCA,the killing rate decreased to 92.62% and 93 .57%,respectively.Conclusion UCA remained on the oper-ative field has shielding and antagonistic effect on iodine disinfectant.
ABSTRACT
Objective To realize the contamination status of dental unit waterlines (DUWL)in general hospitals, and provide scientific evidence for making preventive measures.Methods Three hospitals were selected for study, water source adopted by hospital A,B and C was running water,reservoir water,and filtered water through reverse osmosis filtration system respectively,specimens of dental handpiece spray water and flushing water of dental chair units were collected quarterly,total bacterial colony in water were detected.Results The qualified rate of source wa-ter,handpiece spray water,and flushing water in hospital A was 75.00%(3/4),0 (0/40)and 0 (0/40)respectively,col-ony count of handpiece spray water and flushing water was (1.20×103 -5.53×104 )CFU/mL(M=3.80×104 CFU/mL) and (2.11×104 -1.66×105 )CFU/mL(M=4.80×104 CFU/mL)respectively.The qualified rate of source water,hand-piece spray water,and flushing water in hospital B was 50.00%(2/4),60.00%(24/40)and 72.50%(29/40)respectively, colony count of handpiece spray water and flushing water was (0.00 -3.71 ×106 )CFU/mL(M=83.00 CFU/mL)and (0.00-2.39×106 )CFU/mL(M=72.00 CFU/mL)respectively.The qualified rate of source water,handpiece spray wa-ter,and flushing water in hospital C was 100.00%(4/4),55.00%(22/40)and 65.00%(26/40)respectively,colony count of handpiece spray water and flushing water was (0.00-6.20×103 )CFU/mL(M=96.00 CFU/mL)and(0.00-1.63×103 )CFU/mL(M=87.50 CFU/mL)respectively.Conclusion Water of DUWL in general hospitals is seriously con-taminated,disinfection and standardized management of source water and DUWL must be strengthened.