[Infection risk through the reuse of "used" cylinder ampoules for dental local anaesthesia (author's transl)].
The phenomenon of so-called syringe internal infection with cylinder ampoule syringes customarily used in dental local anaesthesia is discussed from the view-point of infection hygiene. The contamination rate of the residual content-of used cylinder ampoules has been determined by means of bacteriological model tests with E. coli under the conditions of the cannulae removal phenomenon and the reflux phenomenon caused by tissue overpressure resulting from the injection. It has been shown that - as result of changing a contaminated cannula with the commonly used Uniject cylinder ampoule injection system, the probability that the cylinder ampoule residual contents are infected in 93% using metallic head cannulae and 78% with disposable screw-on cannulae; - even with the lever syringe systems for intraligamentary anaesthesia, changing contaminated, ultra-thin special cannulae leads with 11-12% probability to infection of the cylinder ampoule residual contents; - injections with a tissue counterpressure of only 1 atm result in a 100% contamination rate of the cylinder ampoules through reflux phenomena. The test results lead to the indispensable hygienic demand that - irrespective of which injection system is used - used cylinder ampoules must not be reused with other patients. The increasingly high contamination ratio (0.5 - 1.0%) of our population with hepatitis B viruses places increased demands on the need for care on the part of the dentist and physician.
D000766:Anesthesia, Dental / Q000295:instrumentation*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D004340:Drug Contamination; D004349:Drug Packaging; D006801:Humans; D007239:Infections / Q000209:etiology*; D012306:Risk; D013594:Syringes
D000779:Anesthetics, Local
Infektionsrisiko durch Weiterverwendung "angebrauchter" Zylinderampullen bei der zahnästhesie.