Clinically, the benefit of the washer disinfector is that it is able to properly clean instruments prior to sterilization, whereas manual cleaning is rarely done effectively or consistently and cannot be satisfactorily validated. As regards the efficacy of washer disinfectors, the validation process ensures instruments are being cleaned effectively and the washer disinfector is checked on a regular basis. There are daily and weekly user checks that should be carried out which will ensure each cycle is effective and compliant. These include protein testing that will show by colour any contamination of instruments. Regular use of this simple test will show if the washer disinfector is working effectively or not, and should give the user confidence. Conversely, how can you prove with manual cleaning each instrument is going through the same consistent and effective process when the procedure is so open to human error and inconsistency? How can the risks of sharps injury be properly mitigated in such a process?
A simple swab test is also sufficient to show that many instruments manually cleaned are not free of contaminants prior to autoclaving. The problem with this is that organisms trapped within or beneath contamination will not be contacted by the steam and will not reach a sufficient temperature to be killed off. The instrument is then not sterile and is contaminated with something that might be transferred to the next patient or to a dental worker through a sharps injury. Usually this will not cause an adverse effect, however in some cases the outcome could be serious or fatal.
This theoretical risk is accepted by most people, but their respective risk assessment of the real potential for contamination varies widely. Many dental workers will state a lack of evidence surrounding actual cases of cross contamination, express scepticism there is much of a risk, and often ask how many people have actually died, or even been shown to have contracted anything from a dirty or non-sterile dental instrument.
However, many microbiologists see the cleaning of instruments as a more important process than autoclaving and stress autoclaving dirty instruments is not effective and may be prevalent throughout dentistry.
None of this might matter if the risk of actual contamination is sufficiently low. In this regard the microbiologists are as frustrated as dental professionals at the lack of real studies and hard evidence to conclude one way or another. All that microbiologists can do is try and look at comparable situations in other clinical and health care environments. Their interpretation of this evidence, taking a risk adverse view due to the potential seriousness of the consequences of dental cross contamination, is generally that the risk should be assumed to be serious and appropriate precautions taken.
A threat microbiologists have particular concerns over is the global growth of resistance to antibiotics. Such is the potential of this particular threat in the coming decades that some have described it as a potential Armageddon scenario. Without antibiotics we lose the ability to perform many life saving major surgeries almost completely. Resistance to antibiotics can certainly be transferred between individuals through oral microbes. Once again, the only real question here is how high is the risk of such cross contamination? Many microbiologists feel the risk and consequences are sufficiently serious that a better standard of instrument cleaning through the use of washer disinfectors should be mandatory.
Another valid point they might make is that we are taking precautions not just to combat a problem that might or might not exist right now, but also to ensure our intake of people from areas of the world, where the prevalence of Hep B, Hep C, or TB, for example, is higher than in the UK, does not pose a health threat in the future. The effective way to do this in the dental surgery is through good standards of basic infection control procedures.
There are around 4m health care acquired infections each year in Europe. These lead to around 37,000 deaths per year, the equivalent of an aeroplane crash per day. Such infections take up 16m healthcare days in treatment, and cost around €5.5bn pa. How many dentally acquired infections there might be is not known to any degree of accuracy, but the magnitude of the problem in other areas of healthcare suggests that it is likely to be an issue in a dental surgery sufficient to require close attention to the highest standards of instrument cleaning and decontamination.
Ultimately the question might be what do we do when we just don't know what the risk might be but potentially the consequences of inaction are very serious?
The answer from the World Health Organisation, and our own Health Act 2006, is that surgeries should take universal precautions. That means they should assume every patient they see is infected with something to be avoided. The Health Act 2006 and its subsequent revisions point the way for dentists and state they should comply with the advice given in HTM 01-05 to ensure they use a process which provides instruments sterile at the completion of the process (this is different to, for example, a hospital operating theatre, where instruments must be provided sterile at the point of use).
So, does this mean the dentist is compelled to use a washer disinfector? Are they compelled to follow HTM 01-05 which is the same as all Health and Technical Memoranda, an advisory document? Or can the dentist simply ignore the advice in HTM 01-05 and continue in whatever manner they please? Is there perhaps something in the middle? The situation looks more confusing because even European standards such as EN 13060, which should be the gold standard, are not statutory, merely a statement of agreed procedure.
The answer lies in the Health Act of 2006 and subsequent revisions which does make clear that advice given is not compulsory but that not following the advice would require the surgery to demonstrate a procedure with an outcome that is at least as good and can be justified to an inspecting body. The Health Act 2006 is a statutory document, it is the law.
Expressing scepticism regarding the evidence base of HTM 01-05 is not the same as demonstrating an effective alternative. The requirements of the Health Act 2006 are mandatory, they can be implemented through following HTM 01-05 or by an alternative method which satisfies an inspecting body.
According to HTM 01-05 the alternatives open to the dentist for cleaning dental instruments prior to autoclaving, assuming they have no viable new alternative, are manual cleaning or a washer disinfector.
So a dentist is not compelled to use a washer disinfector. However, they would have to demonstrate they were following the proper procedure for manual cleaning instead. In practice, the requirements of this procedure are near impossible to follow within a reasonable time frame and given the pressures of a surgery environment. Temperature of the water needs to be constantly monitored with a non mercury thermometer, detergent concentration should be monitored, only long handled single use brushes should be used, each instrument should be scrubbed, beneath the water, for a considerable time and then each individually checked beneath an illuminated magnifying source and so on. The reality is this process is almost impossible to practically follow and do anything else in the day other than scrub instruments. The process is rarely, if ever, followed properly. However, if the dentist does not wish to use a washer disinfector then they must be able to demonstrate compliance to the correct procedure. Many may well feel the use of a washer disinfector is a more practical solution than adhering to the full manual cleaning procedure. If they wish to meet best practice standards (and what clinician would state that they didn't want to be operating to best practice?) then manual cleaning is not acceptable.
None of the above even attempts to address the risk of sharps injuries inherent in the manual cleaning process. Presumably there are also issues around employment conditions and duty of care that dentists will need to address separate to the contamination risk.
Compliance monitoring will be carried out by the CQC. These inspectors may or may not initially focus in the area of decontamination. Regardless, the surgery will still be obligated to meet the essential requirements of HTM 01-05 which include an appointed decontamination lead, written policies and procedures, and a written plan which outlines a road map to best practice for the surgery.
It seems likely many surgeries will not have complied with all of the essential requirements by the CQC registration date of April 1, 2011. On the other hand many surgeries have grasped HTM 01-05 positively and have moved straight to Best Practice. It appears that the effect of HTM 01-05 will be to drive decontamination standards higher as intended, but there is a long way to go to convince the profession of the need, and education and communication remains lacking.
Out of all of this debate the health department has decided the risk and consequences are sufficient to require the dental industry to tread a risk-adverse path and raise their standards of dental decontamination.