Sir, we read with interest the commentary on our article entitled A study of visual and blood contamination on reprocessed endodontic files from general dental practice (BDJ 2005; 199: 522–525) and noted that '...a decontamination programme reported by Paraschos et al. appears to be satisfactory...'1 — a close inspection of this method reveals that it involved pre-treating soiled instruments with chlorhexidine. The use of chlorhexidine to clean instruments is a poor choice of cleaning agent, since this chemical tends to stick to proteins and various surfaces rather than exert a detergent action. The use of chlorhexidine for example, in surgical hand scrubs, for cleaning instruments has been highlighted as poor practice and is not recommended in Scotland.2 Advice on alternative agents for use as detergents can be found online at www.show.scot.nhs.uk/scieh/.

We recommend that practitioners do not use chlorhexidine containing agents for cleaning dental instruments.