An appraisal of difficult to clean dental instruments

Risk assessments for reducing the potential for transmission of vCJD have highlighted the importance of pre-sterilization cleaning. Appropriately designed instruments to facilitate the cleaning process are central to risk reduction. Design features which result in instruments which are ‘difficult to clean' (DTC) include the use of connectors, joints, lumens or in-accessibility to inspection. Alternatives to DTC devices are redesign or single-use instruments. If implemented, this would have significant implications for dentistry. OBJECTIVES: To perform a risk assessment for the decontamination of dental instruments. METHOD: A scoring system for assessing the ease of reprocessing instruments was devised, based on the type of material, surface morphology and the presence of the design features likely to impede cleaning (Instrument complexity score (ICS)). Hand instruments were then scored for their vCJD risk (ACDP/SEAC 2003) and the risk for other healthcare acquired infections (Spaulding 1966). RESULTS: The devised scoring system proved useful for prioritising devices at increased risk of transmitting infection. Many devices were identified that carried a high complexity score, were invasive and required sterilization prior to re-use. With the exception of procedures where the instrument came into contact with the lingual tonsillar tissues, all were low risk for vCJD. CONCLUSION: An instrument complexity scoring system can help prioritise those devices that present a higher risk of infection. Such instruments may then be subject to re-design or replaced with single use devices. This study was carried out by the Joint Dental Decontamination Working Group, Scotland.