Using Computational Fluid Dynamics To Evaluate the Role of Air Purification in Reducing Fallow Time in Dentistry

The Problem

Waiting for airborne particles to disperse safely costs the dental industry time and money.

In dentistry, fallow time is the time required for airborne pathogens to settle out of the air and mitigate the risk of airborne infection transmission to dental professionals and staff. The current recommendation is ‘60 minutes’ of fallow time. This means that dentists need to wait for ‘60 minutes’ before they can proceed with another patient/process.

The Solution

Research concluded that air purifiers can help in significantly reducing waiting times in dental practices.

Using a computational fluid dynamics software, we created a virtual dental surgery and simulated a ten-minute aerosol generating procedure. We then modelled air flow in the room with no ventilation, and then in the same room with an air purifier at a throughput of 430m3 h-1, and subsequently in the room with one open window providing 6 ACH and no purifier. The particles released were monitored and their behaviour and airborne time measured and collated. Therefore, our MedicAir air purifier, engineered and developed by medical professionals themselves, showed a drastic fall in the required fallow time. This helps ensure cleaner and healthier air for the staff and for the customers.

View Product

The Result

Our findings suggest that the use of an air purifier greatly reduces the total particle volume in the air and could greatly reduce the risk of infection transmission in a dental surgery.

The results of our simulations evidence that, based on this study, there is a drastic reduction in the time taken to clear 99.9% of air borne particles from the air, when compared to the open window model. The room with no ventilation had a total particle number at 600s of 4.5 million, which required 8400s to reduce by 99%. With an open window providing 6 ACH, we obtained a value of 2500s for a 99% reduction in airborne particles and a similar peak particle volume. Conversely, when using an air purifier throughout the procedure, the peak particle number was ten times lower than the peak number without ventilation or with an open window, and after the particle injection, 99% airborne particle reduction was achieved in 60s. Our findings suggest that the use of an air purifier greatly reduces the total particle volume in the air during the aerosol-generating procedure, as well as the fallow period needed. The values found with 6 ACH and an open window are corroborated in other literature, which provides some validation to our testing modality. The use of air purification could greatly reduce the risk of infection transmission in dental surgeries.