Decontamination in dentistry – how has it changed throughout history?
From the very beginning of infection control up to the Covid-19 pandemic, Patrick Masheder explores the evolution of decontamination in dental practices.
The Covid-19 pandemic
Britain is often at its best when the country’s back is against the wall. The political response to the Covid-19 pandemic is something that will only be decided when sufficient time has passed for historians to make a judgement. But regardless of this, the UK rose to the challenge made by an unprecedented peacetime public health threat magnificently.
The UK’s scientists led the way in creating an effective vaccine. British industry stepped up to manufacture thousands of ventilators and switched production to PPE materials almost overnight. The public also played their part by staying at home and taking extra precautions.
Quite literally in many cases, Covid-19 changed the way society worked. In addition, it changed the way people thought about good hygiene. Hand washing, the disinfection of surfaces and regular cleaning became part of everyday life.
In the dental practice setting much of this was already second nature.
Laura Edgar is managing director of Aura Infection Control, the UK’s leading experts in dental decontamination. She believes Covid helped concentrate minds like never before. ‘Pre-Covid I think the industry went along with the guidelines because they were the legal framework it operated under.
‘But how many dental practices asked if they could go further? How many placed a lot of importance on infection control and dental decontamination leads?
‘Almost overnight this aspect of the industry went from something that had to be done to something that was at the forefront of everything the industry was doing. People sat up and took notice for the first time in more than a decade. And ultimately that was a very good thing.’
‘The saviour of mothers’
The importance of good hand hygiene is well known.
The lessons were learned as long ago as 1847 when Hungarian physicist Ignaz Semmelweis had a ‘eureka’ moment. He noted a relationship between puerperal fever and doctors who refused to wash their hands before treating patients after performing autopsies.
Ignaz saw a miraculous 90% reduction when he instituted a strict hygiene policy in his clinic. Despite this, he was widely derided for his theories that hand washing could reduce mortality. This is because the germ theory of disease was not then widely accepted.
Today he is considered to be a founding-father of modern hygiene and is widely known as ‘the saviour of mothers’.
A uniquely intimate profession
Nearly two decades after Semmelweis’ discovery, the cleansing of wounds with carbolic acid was suggested as a gangrene preventative. One of the earliest adherents to this concept was a London dentist, Ashley Barrett. He used carbolic acid to prevent infection in fillings and treatment of dental abscesses with great success.
So it is that the dental profession has been at the cutting edge of hygiene for more than 150 years.
This should be no surprise as dental work is uniquely intimate. Dentists must place their hands in patients’ mouths and hand pieces create aerosols. In addition, the throughput of patients is far greater than in, say, a hospital operating theatre.
That’s why the industry has led the way in the use of masks, protective eyewear such as visors glasses, good ventilation, high velocity suction, rubber dams and water-cooled hand pieces.
Can we do it better?
But Laura says: ‘Often it takes a public health emergency to prompt a period of self-reflection; to look at what we are doing and ask: “Can we do it better?”
‘The emergency of HIV/Aids during the 1980s is a good example of this. Suddenly dentists began to question their methods. As a result, this led to the widespread adoption of autoclaves for sterilisation rather than boiling water. Sharp handling procedures were also tightened up considerably and there was widespread adoption of PPE.
‘During this time the dangers of biofilms in water lines was highlighted and new measures were adopted to keep units clean, such as regular flushing and disinfection.’
In 1991, the British Dental Association issued guidance on cross infection control (sheet A12) which was developed with the Department of Health to be in line with then-current NHS infection control procedures.
The sheet offered guidance on implementing safe and realistic infection control practice and procedures in general dental practice and was one of the most requested documents published by the BDA.
The Creutzfeldt-Jakob disease scare
‘But the biggest step-change was probably the CJD scare in the late 1990s,’ says Laura. ‘This was the second major public health emergency that drove serious change in less than 10 years.’
The link between infected beef and vCJD sent shockwaves through the country. But it had added concern for dentists because the infective agent was found to be present in animal dental pulp.
Since 2000 there have been a handful of cases of vCJD transmission linked to dental work.
‘This led directly to HTM 01-05, decontamination in dental practices, which were a huge advance over everything that had gone before,’ explains Laura.
‘Suddenly, everyone had a set of strict guidelines which laid down what they should and should not be doing. There was a greater focus on single-use instruments, effective sterilisation of reusable instruments, ensuring surfaces were clean – and not just to the naked eye – greater hygiene, use of PPE and scrupulous decontamination of water lines.’
HTM 01-05 is now 14 years old and, Laura reckons, overdue a thorough overhaul.
‘Lessons should not be forgotten’
‘The guidelines are still the standard by which the dental industry works but there have been so many advances in technology since 2009 that, in part, the decontamination processes are potentially far more effective.
‘It would serve the industry well to draft new guidelines taking into account the advances made and, of course, the lessons learned during the Covid pandemic when the standard operating practices were changing almost on a week-by-week basis.’
And as the country looks nervously at Covid in the rear view mirror as it gets back to the new normal, Laura is anxious that the lessons should not be forgotten.
‘At the height of the lockdown restrictions around dental treatment were so tight that they had to change eventually. Otherwise, it wouldn’t have been possible to offer effective care to patients except in an emergency situation – and no one wants that.
‘But having been so diligent about things like hand hygiene and infection control, we have to keep it up. There can be no going back to “how it was before”.
‘The pandemic has prompted the industry to set a new standard and it’s up to all of us to ensure that we meet it.’
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