Failure of non-vacuum steam sterilization processes for dental handpieces

Winter, S., Smith, A. , Lappin, D., McDonagh, G. and Kirk, B. (2017) Failure of non-vacuum steam sterilization processes for dental handpieces. Journal of Hospital Infection, 97(4), pp. 343-347. (doi: 10.1016/j.jhin.2017.09.004)

Abstract

Background: Dental handpieces are used in critical and semi-critical operative interventions. Although a number of dental professional bodies recommend that dental handpieces are sterilized between patient use there is a lack of clarity and understanding of the effectiveness of different steam sterilization processes. The internal mechanisms of dental handpieces contain narrow lumens (0·8-2·3mm) which can impede the removal of air and ingress of saturated steam required to achieve sterilization conditions. Aim: To identify the extent of sterilization failure in dental handpieces using a non-vacuum process. Methods: In-vitro and in-vivo investigations were conducted on commonly used UK benchtop steam sterilizers and three different types of dental handpieces. The sterilization process was monitored inside the lumens of dental handpieces using thermometric (TM) methods (dataloggers), chemical indicators (CI) and biological indicators (BI). Findings: All three methods of assessing achievement of sterility within dental handpieces that had been exposed to non-vacuum sterilization conditions demonstrated a significant number of failures (CI=8/3,024(fails/n tests); BI=15/3,024; TM=56/56) compared to vacuum sterilization conditions (CI=2/1,944; BI=0/1,944; TM=0/36). The dental handpiece most likely to fail sterilization in the non-vacuum process was the surgical handpiece. Non-vacuum sterilizers located in general dental practice had a higher rate of sterilization failure (CI=25/1,620; BI=32/1,620; TM=56/56) with no failures in vacuum process. Conclusion: Non-vacuum downward/gravity displacement, type-N steam sterilizers are an unreliable method for sterilization of dental handpieces in general dental practice. The handpiece most likely to fail sterilization is the type most frequently used for surgical interventions.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Winter, Ms Sandra and Smith, Professor Andrew and Lappin, Dr David and McDonagh, Mr George
• Authors: Winter, S., Smith, A., Lappin, D., McDonagh, G., and Kirk, B.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Dental School
• Journal Name: Journal of Hospital Infection
• Publisher: Elsevier
• ISSN: 0195-6701
• ISSN (Online): 1532-2939
• Published Online: 10 September 2017
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in Journal of Hospital Infection 97(4):343-347
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher