Key Points
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Disinfection of dental impressions must be undertaken to prevent transmission of bloodborne viruses to members of the dental team.
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The correct dilution of the disinfection agent should be observed.
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The dentist should indicate clearly to the dental technician that disinfection has been undertaken.
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Repeat disinfection of impressions by technicians risks their dimensional stability.
Abstract
Introduction The responsibility of ensuring impressions have been cleaned and disinfected before dispatch to the dental laboratory lies solely with the dentist. Uncertainty of impression disinfection risks both the health of the receiving dental technician and potential repeat disinfection of an already disinfected impression with detrimental consequences for its dimensions. Objective To ascertain, from the perspectives of dentists and dental technicians, current impression decontamination and disinfection practices with, in the case of the technicians, an estimate of the relative prevalence of contaminated voids within apparently disinfected impressions. Design Anonymous postal questionnaire. Method Dentist (n = 200) and dental technician (n = 200) potential participants, selected at random from the registers held by the General Dental Council, were invited to complete an anonymous postal questionnaire that sought to establish current practices and perceived effectiveness of impression disinfection. Results Questionnaire return rates of 42.1% and 31.2% were recorded for dentists and dental technicians respectively. A wide range of solutions, at different dilutions of the same product, was used by the dentists to disinfect dental impressions. 37.2% rinsed the impressions with water, and 2.6% always brushed debris away, before disinfection. 24.7% of dentists did not inform the laboratory of disinfection. Irrespective of the disinfection status of the received impressions, 50% of the responding dental technicians disinfected all impressions. 95% of them had received blood-contaminated impressions. 15% had encountered blood-filled voids upon trimming back the peripheries of impressions. 64.7% were confident that the impressions received by them had been disinfected by the dentists. Conclusions Compliance with good practice is less than ideal and education in impression disinfection for both dentists and dental technicians is required to address this.
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Almortadi, N., Chadwick, R. Disinfection of dental impressions – compliance to accepted standards. Br Dent J 209, 607–611 (2010). https://doi.org/10.1038/sj.bdj.2010.1134
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DOI: https://doi.org/10.1038/sj.bdj.2010.1134
