Is it really about safety? Should we rethink the strategy to put dentistry back on track?
Corona virus SARS-CoV-2 has taken its toll on human lives, lifestyles and much more. Every public authority wants to do its best to get this deadly virus under control. We have seen telling effects on the lifeline of dental practices be it NHS or private, affecting the financial bottom lines, work-flows, treatment provisions and so on. Amidst all this, patients are suffering from unprecedented pain, missed treatments, complications which are wholly avoidable. Just a few months ago we never thought this could ever happen to a buzzing dental industry despite its own shortcomings.
There is no doubt that the word AGP (aerosol generating procedure) sends an electric current down every dental practitioner’s spine. The SOPs, risk assessments, FFP3s, respirators, fallow, air changes, the sweat underneath and safety procedures that every practice needs to comply with, in this ever-changing world.
We need to make sure we do not fall prey to the interchangeable use of the word AGP. It feels like politicians, public authorities and other non-dental organisations seem to equate dental aerosols to the medical aerosols from a patient’s respiratory tract. There is no doubt that every exposure to the secretions from naso-tracheo-bronchial tract is harmful when laden with virus. The dental aerosol is of a different nature and may be less of a harm due to reasons mentioned below. There is a risk of disease transmission through salivary secretions and it is still not proven yet if saliva can cause human to human transmission.
Dental aerosols have multiple factors which make them less harmful even if the subject in question is an asymptomatic carrier reminding ourselves that we do not see symptomatic Covid-19 patients. The viral load in these asymptomatic patients is so low that the risk of disease transmission is low (R=0.2). There is a robust risk assessment within every dental practice these days. Every patient has pre-treatment rinse with hydrogen peroxide which further reduces the viral load. The dental unit water lines are either distilled water through reverse osmosis or has anti-bacterial and anti-viral treatment through manufacture recommended processes. Essentially the dental aerosol is a sterile water spray as rubber dam is used on most occasions. Even if the viruses are present within the aerosol, the load is significantly low to cause disease in other patients or staff. Let us not forget all staff are geared up with enhanced PPE to protect themselves too.
What we really need to worry is the impact of every dental visit. By carrying out an examination or simple procedure (non-AGP) in an asymptomatic carrier, the operating team carries similar risk, with mouth wide open and exposed to viral shedding from patient’s respiratory tract. It is not necessary that the transmission occurs through the AGP events alone but equally non AGP events such as check-up, non-surgical extractions, abscess drainage and many more where direct aerosol is not generated must be treated with the same risk management approach.
Are we missing the point here? Is it convenience, ignorance or mis-interpretation of scientific data? We must think this through carefully and stop creating a world of baseless assumptions. Any asymptomatic carrier of SARS-CoV-2 who coughs or gags can shed more viruses during a simple visit to dental practice irrespective of an AGP taking place. Let us not pretend non-AGPs are safe.
Is it not time to revalidate our beliefs and move with some pragmatism, amidst the rhetoric of lack of evidence? Is it fair that dental practices are still being imposed with multiple guidance with far reaching public health and financial impact?
Is more aggressive and rapid testing including reporting Ct (Cycle threshold) values the answer to what is a formidable challenge? Cycle Threshold is an indicator of the viral load in a given patient. By simply saying a patient is Covid +ve or -ve is not enough as we do not necessarily know the risk of disease transmission.
If we can determine how significant the viral load is, it will help clinical teams to carry out the work safely with appropriate PPE.
Reference:
- https://www.eurosurveillance.org/content/10.2807/1560- 7917.ES.2020.25.32.2001483#html_fulltext
- Seong Eun Kim et al Viral kinetics of SARS-CoV-2 in asymptomatic carriers and presymptomatic patients; International Journal of Infectious Diseases; 95 (2020) 441–443.
- Izzetti R , Nisi M, Gabriele M, and Graziani F; COVID-19 Transmission in Dental Practice: Brief Review of Preventive Measures in Italy .Journal of Dental Research, 2020,Vol99(9)1030-38.
- Robinson Sabino-Silva et al; Coronavirus COVID-19 impacts to dentistry and potential salivary diagnosis. Clinical Oral investigations, 2020 24:1619-21.
- Yuqing Li et al. Saliva is a non‐negligible factor in the spread of COVID‐19. Molecular oral microbiology, https://doi.org/10.1111/omi.12289
- Stephen Harrell and John Molinari; Aerosols and splatter in dentistry: A brief review of the literature and infection control implications. The Journal of the American Dental Association: Volume 135, Issue 4, April 2004, Pages 429-437.
- Yanfang Ren, Changyong Feng, Linda Rasubala, Hans Malmstrom, Eli Eliav. Risk for dental healthcare professionals during the COVID-19 global pandemic: an evidence-based assessment. Journal of Dentistry DOI: https://doi.org/10.1016/j.jdent.2020.103434