Sir, I would like to thank Dr Cockcroft for his response to my letter HTM 01-05 revision (BDJ 2009; 207: 144–145) where it seems we can at least agree that the quality of evidence used in one aspect of HTM 01-05 may have fallen below that which the DH usually employs.1

I know Dr Cockcroft feels as I do that 'It is essential that guidance from DH is, where possible, based on robust evidence', as he recently stated in a CDO newsletter.2

As if to reinforce to us all how critical it is to get centralised guidance right before its imposition, Dr Cockcroft explains the consequences of not following such newly created guidance to the letter, bringing down the wrath of legislation in NHS regulations, the new Care Quality Commission and even Fitness to Practise GDC disciplinary procedures to bear on anyone who dare vary or question such guidance!

It may be of course that the unavailable 60 plus references alluded to in Dr Cockcroft's reply* meet the highest evidence standards of Cochrane level 4 or even level 3 GRADE3 quality, so I am mystified as to why these have never been produced for public or professional scrutiny. Indeed if they are so reliable/compelling that would be reassuring. If, however, they are at the lowest GRADE 1 of evidence (expert opinion and poorly controlled trials) then surely one must question whether such extensive, expensive and potentially retrograde changes purporting to be 'best practice', should be made compulsory before any such high-quality evidence is further commissioned and evaluated.

Given the existing publicly available evidence that vCJD deaths have only totalled 167 over 20 years, are in steep decline since their peak in 2000 and it is predicted there will only be one or two new vCJD cases occurring per year now, one must ask why then this HTM 01-05 disproportionate response when NO cases have ever been associated with dentistry?4

Any risk assessment should take into account 'Failure Modes' and 'Effects Analysis' (FMEA), where failure modes are any defects in a process, design or item (eg: WDs) and effect analysis looks at the effects of those failures.5 Immediately the published literature would raise FMEA concerns where proposed HTM 01-05 'best practice' methods using high-temperature washer disinfectors (WD) leave significant amounts of proteins on sterilised instruments consistently.6-10

Thus for such decontamination stages pre-autoclaving, shouldn't emphasis be on ensuring existing protocols are used routinely,11 physical scrubbing,12 ordinary washers operating at lower temperatures that don't bake on proteins,13 or/and an ultrasonic bath stages14 as used currently, which have lower FMEA risks and provide safer, superior and more evidence-based results than those about to be enforced in HTM 01-05 best practice?

I can do no better than quote the DH's own report in 200615 looking at current WDs/autoclaving systems which states, '...the high levels of retained protein burden after decontamination through typical NHS systems is itself a matter for concern'.

We need scientific validation first, otherwise printer-validation on high-temperature WDs may simply prove we have left 'high levels of retained protein burden' on all our dental instruments instead – I can just imagine patient consent to that not being very popular!

I hope therefore that Dr Cockcroft and the wider BDJ readership can be reassured that my motives in asking for urgent evidence-based revision now, before the current HTM 01-05 is printed then imposed, are honourable. Thus my request to help ensure this important new guidance is all that it can be, in the wider public interest, still stands.

* Editor-in-Chief's note: Dr Cockcroft has now provided the BDA with a list of 90 references in relation to HTM 01-05 but without Grading, which he has noted is to follow soon. In the meantime the BDA's Health and Science Committee is beginning the not inconsiderable task of analysing the references provided.