How safe is your suction?

suction unitDürr Dental highlights the importance of the suction unit in your practice and how to achieve high volume evacuation. 

The role of the suction unit is often misunderstood.

Yes, it removes saliva, blood and the spray mist caused by high-speed turbines; however, it also contributes significantly to the control of dental aerosol.

Arguably, with the onset of COVID-19, this last year has now elevated a humble (and rather unglamorous) piece of dental equipment to a newly elevated status! More than ever, dental professionals are concerned about the aerosol in their surgery and the impact it has on safety.

What is HVE?

One must employ high volume evacuation (HVE) in order to control aerosol. HVE is the rate at which a suction device draws a volume of air over a period of time.

There’s a specific range into which your unit must fall in order to classify as achieving HVE – between 280 and 350 litres per minute. With an optimum target of 300 litres.

Any suction device that falls below 250 litres will not remove sufficient aerosol from the intra oral site. It is not therefore in the category of HVE.

Conversely, too much evacuation is also not good. It can result in the removal of cooling water from the instrument before achieving its desired effect. This impacts the safety and comfort of dental procedures.

Between the parameters of 300-350 litres per minute, aerosol is reduced by up to 90%, protecting both patients and clinicians.

How to achieve HVE?

Controlling aerosol before it leaves the mouth is the ultimate goal. But how can we best achieve HVE?

The suction system must be installed with correct pipework and layouts so that the clinician’s choice of suction cannula can harness the optimum capability of the unit.

Unsurprisingly, the larger the aperture of the suction tip, the greater the potential for aerosol control; saliva ejectors and cannulas with a smaller aperture will not achieve the desired flow rate. An aperture of 16mm or greater delivering the best results.

Maintenance is also critical. When you think of all the components you aspirate, they naturally have the potential to adhere to pipework and components. This results in a potentially dangerous colony of biofilm.

The daily use of a suction disinfectant, such as Orotol Plus, will ensure bacteria, fungi, and viruses are all deactivated.

However, as well as killing biofilm, it is also essential to remove mineral deposits and dental materials that can build up over time. Doing so will ensure the longevity and efficacy of your suction system. Failing to remove the build-up will reduce the aperture of the pipework.

Over time, this impacts the vacuum airflow of your apparatus. Previous HVE will not be achieved, which will mean that aerosol will no longer be controlled as effectively.

As well as potentially exposing you and your patients to unnecessary risk, a build up of deposits can also damage the suction pump. This can invalidate manufacturer warranties and result in unnecessary down time.

Such scenarios are preventable by descaling your unit and pipes once a week, with a descaler such as MD555.

Engineers…your suction unit’s best friend

A dental engineer will perform a quick test to assess the performance of your suction system. This is the only way to ensure whether a HVE device is working properly.

The engineer will test the volume of airflow at the large volume (16mm) suction hose. Various things can impact efficacy including the age of the equipment, and the build up in the evacuation line.

If necessary, they can undertake a service to ensure your equipment is working at optimal capacity.

Everyone now understands the impact of aerosol on the spread of disease. It’s reassuring to know that one major risk within your surgery, can be eliminated through professional maintenance and routine care.

Using HVE as a preventative safety measure now makes more sense than ever. HVE devices also offer better assurance against potential liability claims.

It is up to individual dental teams. They must ensure that they are taking every measure necessary to maintain safe and sanitary working environments.

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