COVID and the Failure to Challenge

by John Hardie, BDS, MSc, PhD, FRCDC

The July 2021 Oral Health editorial was an opinion piece titled, “They Never Gave Us Hope…” It succinctly described why, regarding the COVID-19 pandemic, the inept actions of politicians, public health administrators and the media were promoting despair rather than hope.1 Fortunately, a year later, that despondency has been replaced by one of cautious optimism as many of the irrational fears associated with the pandemic begin to fade. As this occurs, it is pertinent to ask if dentistry rose to the challenges presented by COVID-19.

Dentistry prides itself on being a science- and evidence-based discipline. The Scientific method (a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses) ought to be governed by a high degree of scepticism which permits all conclusions, assumptions, guidelines and standards to be challenged. Criticism is the backbone of the scientific method. The level of evidence accredited to a clinical recommendation is a measure of its likely efficacy. Level five, the lowest or minimally reliable level of evidence, reflects case reports or expert opinion. Level one, the highest or most reliable level of evidence, is based on the results of randomized controlled trials.2,3 How well dentistry rose to the unique challenges imposed by SARS-CoV-2 is a mirror of the degree to which it satisfies its science- and evidence-based foundations.

The HIV/AIDS crisis of the mid-1990s was instrumental in promoting the idea that dental practice was a source of infectious disease transmission. This assumption has driven a dental infection prevention and control industry resulting in a multitude of recommendations designed to prevent dentally acquired infections. The frequency and nature of these infections prior to, and following, the introduction of recommended control methods has never been ascertained. Therefore, the necessity for, and the effectiveness of, such preventive measures have never been scientifically established. However, they have been justified by the opinions of anonymous “experts” whose collective wisdom represents the lowest level of evidence. This means that all infection prevention and control recommendations adopted for COVID-19, including personal protective equipment, are based on the flimsiest of foundations that ought to have been challenged years ago, and yet were not.

The concept of asymptomatic transmission has been a major driver of many COVID-19 inspired restrictions imposed on dentistry. A confirmed case of an infectious disease is dependent on the co-existence of two essential factors: One, the presence of its characteristic symptoms and two, identification of its causative agent.4 Using the PCR test to confirm the presence of infectious SARS-CoV-2 is notoriously unreliable with false positive rates as high as 97% being reported.5,6 Without the presence of both factors, there can be no confirmed case of COVID-19. Patients without symptoms are, by definition, well. This means that patients exhibiting no cold- or flu-like symptoms could be treated as they would have been prior to COVID-19. Symptomatic patients could have their treatment delayed until the symptoms abated. Symptomatic emergency patients could be treated with minimal direct care commensurate with the nature of the emergency. Therefore, basing COVID-19 policies on transmissions from symptomless patients is an improbability that ought to have been challenged from the very beginning of the public health response. (Fig. 1)

Fig. 1

Treatment paths. Quarantine only if symptomatic or until symptoms abate.
Treatment paths. Quarantine only if symptomatic or until symptoms abate.

Dental aerosols have been deemed as routes for the transmission of SARS-CoV-2. The transmission of viral infections by this means would necessitate the sequential occurrence of a series of unlikely events. One, an infectious dose of the virus must be present in the aerosols. Two, the dispersal of the virus into the environment must not reduce its virulence. Three, it must remain capable of overcoming the natural defence mechanisms present in the upper respiratory tract of a susceptible host. To date, this remains, at best, a theoretical route for the dental transmission of viral infections. Accordingly, using aerosol transmission viral infection to justify supplementary personal protective equipment and, unprecedentedly, the introduction of fallow times for dental operatories, ought to have been challenged from the very beginning of the public health response.7,8 In fact, if the patients are asymptomatic, their saliva will not be harboring the SARS-CoV-2 virus, and fallow times for operatories are quite unnecessary.

Early in the pandemic it was appreciated that COVID-19 was a condition of distinct demographic characterizations. Overwhelmingly, it had serious consequences for the frail elderly with 90% of COVID deaths occurring in persons with one or more pre-existing chronic conditions.9 Most cases involved healthy adults with minimal consequences. COVID-19 had barely registrable effects on children and teenagers. Data from both Ontario and Canada illustrate that while cases are disproportionally stratified across ages, deaths are overwhelmingly confined to the elderly.10,11 Despite this, and even after excluding possible COVID-19 cases, dental regulatory bodies adopted a one-size-fits-all approach to patient care. This contradicted the very concept of patient- focused treatment, while dramatically increasing the costs of dental care with no appreciable treatment or safety benefits. This revolutionary management of dental treatment ought to have been challenged from the very beginning of the public health response.

Faculties of Dentistry, the Regulatory Colleges and Provincial Dental Associations are responsible for developing and perpetuating the science- and evidence-based nature of the profession through integrated and mutually co-operative activities. This is an undertaking that is exclusively within their respective domains. It is a role that they must not, and cannot, cede to third party agencies such as Ministries of Health, Departments of Public Health or insurance providers. Unfortunately, there is a dearth of evidence demonstrating to what degree, if any, the guardians of our profession challenged the pandemic inspired edicts stemming from non-professional, non-dental government functionaries.

In this context, challenge does not connote defiance. It is simply the imperative basic exercise of the fundamental tenets of science. For example, the academic and professional dental institutions ought to have examined and reported on the quality of evidence (if any) employed by government agencies to support their COVID-based restrictions. The average dentist has the right to know (and must recognize, for effective protection of the patient) whether banning reading material, confining waiting patients to cars, leaving operatories idle for protracted periods, appearing as amorphous thermometer-wielding masked aliens, (Fig. 2) and clogging the environment with discarded protective equipment of dubious utility, were based on rigorously controlled clinical trials, or were merely the abstract musings of anonymous “experts” charged with “doing something” by their political overlords.

Fig. 2

 “Alienating” patients.
“Alienating” patients.

It does appear that the identified challenges were not met. This is certainly not the fault of average practitioners, many of whom were economically disadvantaged (and some who left their practices altogether), by the mandatory adoption of arbitrary COVID restrictions. (Fig. 3)

Fig. 3

Pandemic inspired retirements.
Pandemic inspired retirements.

The COVID pandemic presented dentistry with the unique opportunity of a patient-focused response with recommendations that were based on scientific methodologies designed to reflect the highest level of supporting evidence. Those charged with this highly important task abrogated their responsibility by succumbing to apparatchik government orders without questioning, testing, observing and measuring. In short, they abandoned the Scientific Method that is the foundation of the healing arts. Consequently, dentistry’s response to COVID has not enhanced its position as an independent science- and evidence-based profession.

Fortunately, remediation is at hand. In preparation for the post-Covid era, dentistry must ensure that its infection prevention and infection control practices are commensurate with clinical evidence of disease transmission and not guided by theoretical assumptions, particularly those formulated by “experts” who have little or no knowledge of dentistry. That exercise, if successfully accomplished, will provide dentistry with the knowledge and expertise to challenge future government interferences, no matter how well intentioned. It should begin by
accepting the impossibility of achieving a zero risk of disease transmission.

Oral Health welcomes this original article.


(Only the principal author is identified)

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About the Author

John Hardie As an Oral Pathologist, Dr. Hardie’s career focused on hospital-based dentistry in Ottawa, Vancouver, Saudi Arabia and Northern Ireland. This fostered an interest in infection prevention and control as it relates to dentistry. He has published numerous articles on that topic and presented lectures on it and related subjects throughout North America, the UK, Europe and the Middle and Far East.