Healthcare workers are the frontliners in the fight against COVID-19, where they are risking their lives every now and then to treat their patients. Dental practitioners are among the healthcare service providers who are at the top when it comes to the risk of exposure to the lethal virus. This short review article discusses the background of this pandemic and the potential risks and challenges that dentists face due to the peculiar nature of the profession and some infection control measures to cope with the same.
Keywords: COVID-19, pandemic, dental practitioners
The Novel Coronavirus (COVID-19) outbreak is a bolt from the blue for mankind. It has brought the planet to a standstill- way beyond humans could have ever imagined. To cope with the virus and prevent its transmission, countries are locked down, movements restricted and professional life has been shattered, suspended, cancelled and come to a halt. The shocking and surprising outburst has posed a significant threat to Health resulting in a global public health emergency 1. Interestingly, while the whole world is on one side isolating and maintaining social distancing, healthcare providers are the one and only who are coming in close contact with their patients day in and day out.
As a part of the healthcare industry, dental practitioners have always faced a great challenge for both providing dental care and at the same time protecting themselves from coming in contact with such deadly infections. Dental practitioners work in one of the most dangerous infection prone areas in the body- the mouth 2. Saliva in the mouth is home to a wide range of pathogenic micro-organisms such as viruses and bacteria and thus, the risk involved of getting infected through it is very likely 3. Dental procedures involve face-to-face communication, and with the emergence of such communicable diseases such as COVID-19, dentists have to be extra cautious while adopting infection control protocols in their clinics, it has to be more effective and efficient in addition to the existing setting to minimize cross-contamination 4.
The World Health Organization (WHO) announced the 2019 novel coronavirus as pandemic on 11th March, 2020 and declared the official name as Coronavirus disease 2019: COVID-19. The disease is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)(5). Wuhan city- the capital of Hubei province in Central China is the epicentre of the COVID-19 pandemic, from where it spread worldwide 6. The global death toll from the outbreak nears more than 228 thousand & more than 3.21 million people have been affected from more than 190 countries as of 30th April, 2020.
Coronaviruses – Origin & history
The 2019-nCoV is a newly discovered strain of coronavirus, formerly not recognized in human beings. Coronoviruses belong from the virus family which are common in animals. These are RNA viruses that are enveloped and single stranded 7. They can cause mild infections such as the common cold to severe infections such as SARS (Severe Acute Respiratory Syndrome), MERS (Middle East Respiratory Syndrome), and COVID-19 with symptoms ranging from severe respiratory, hepatic, enteric to neurological 8. These viruses are zoonotic in nature (can be transmitted from animals to humans). A possible transmission of the 2019-nCov is believed to be from the seafood and wildlife market in Wuhan, China, following which it spread by human-to-human close contact. Vaccines or antiviral drugs have not yet been discovered to treat human coronavirus infections 9.
Modes of Transmission of 2019-nCov in The Dental Clinic – The Challenge
According to reports published in the New York Times, dentists are among the top healthcare workers who face the greatest coronavirus risk, as shown in Figure 1 10. The nature of work in dentistry involves frequent exposure to saliva, blood, and other body fluids including exposure to sharp equipments 11. As mentioned earlier, the confronting direct face-to-face communication with the patient while performing dental procedure in the clinic carries the greatest risk of exposure to the virus. In the dental clinic, transmission can be direct, contact, indirect or through aerosol as given in Table 1 12.
Figure 1: Dental Professionals among the top workers facing the greatest coronavirus risk (Adapted from The New York Times)10
The most significant transmission route of SARS-CoV-2 in the dental clinic is droplet and production of aerosol. Large quantities of aerosol and droplet mixed with saliva and blood are generated during dental procedures 13. The virus can suspend in the aerosol as long as three hours after the procedure and can persistently remain on surfaces for prolonged periods. Studies have found that on copper surfaces it can remain up to four hours, on cardboard up to one day, on stainless steel and plastic up to two to three days, making the environment more vulnerable to exposure 14. It must be taken into account that an asymptomatic patient with the infection carries equal risk of spreading the virus similar to a symptomatic patient 15.
Clinical Manifestations of COVID-19
Duration from exposure to the start of symptoms is mostly between 2 to 14 days. Generally, the incubation period is between 5 to 6 days 16. The typical symptoms include:
- Cough, usually dry
- Dyspnea (laboured breathing)
They may be accompanied by 17
- Muscle aches
- Runny nose
- Sore throat
- Diarrhoea and
In severe cases, complications may arise like –
- Acute respiratory distress syndrome
- Viral sepsis
- Renal failure &
Significant risk-factors of COVID-19 involve the presence of co-morbidities 18 such as
- Cardiovascular diseases and
- Respiratory diseases
A positive travel history with risk of viral exposure is another major risk factor. Males are generally more affected (60%) than females and people aged above 70 years are at highest risk for COVID-19 19. All these risk factors lead to poorer prognosis.
Diagnosis and Management
Standard diagnostic method involves reverse transcription polymerase chain reaction (rRT-PCR) testing from a nasopharyngeal swab. CT (Computed Tomography) scan mostly shows characteristics of bilateral pneumonia. It is important to note that the disease can only be properly diagnosed by accessing the symptoms, risk factors and investigations with detailed history taking 20.
The management is enumerated in Figure 2.
Figure 2: General Management of COVID-19
Rendering Dental Treatment in the COVID-19 Pandemic – The Coping Strategies
I. Patient Evaluation and Risk Assessment:
Dental practitioners fall in the high risk group of Healthcare workers who are vulnerable populations for nosocomial infections. Unknowingly, dental practitioners may come in close contact with patients having symptomatic or even asymptomatic COVID-19. In addition, the nature of work & uniqueness of the dental procedures make them more susceptible to exposure. Hence, patient evaluation and risk assessment is the most crucial part, before undergoing any dental treatment. Patient evaluation & risk assessment for COVID-19 is specified in Table 2 21.
Table 2: Evaluation and Risk Assessment for COVID-19 21
II. Need of Emergency Dental Care:
Dental practitioners deal with a majority of dental emergency cases. The most challenging part as a clinician during this pandemic is the management of such dental emergencies including acute dental infections, symptomatic pulpitis and traumatic dental injuries. It is strictly advisable to terminate and immediately postpone all elective and routine dental procedures, until further notifications from the government on the status of the epidemic. Only the emergency services must be kept functional under quality infection prevention and control measures 22. It is very important for the dentist to decide the severity of the dental emergency and accordingly take actions for such patients. Analysis of Emergency Severity is summarized in Table 3 23.
Table 3: Analysis of Emergency Severity 23
III. Treatment Planning:
After analysing the need for dental urgency, a proper treatment plan could be executed as shown in figure 3 24.
IV. Recommendations for Infection Control in The Dental Clinic 25:
- Temporarily stop all dental procedures that produce aerosols, to eradicate the chances for exposure including ultrasonic scalings, tooth preparation with air-rotors, use of 3-way syringe & air abrasion unit.
- Incorporate hand hygiene practices based on the standard guidelines of WHO. Hand hygiene is the best practice for infection prevention & control. Wash hands with soap & water frequently for a minimum of 20 seconds before and after doing dental procedures, after touching surfaces, surroundings & armamentarium. Avoid touching the nose, mouth and eyes. Use a alcohol-based hand rub (ABHR), containing at least 60% alcohol.
- Use personal protective equipments (PPE) including protective eyewear/googles, face shields, masks (WHO recommends use of N95 respirators for aerosol-generating procedures based on the standards of the U.S. National Institute for Occupational Safety and Health which filters almost 95% of airborne particles or FFP2 respirators as per European Union & surgical/medical mask may be used for screening and oral examination), head caps, gloves (disposable), gowns & protective outerwears.
- Antimicrobial mouthrinse before procedures with 1% hydrogen peroxide or 0.2% povidone-iodine can significantly decrease the amount of oral microbes. Important to note that chlorhexidine is not effective against 2019-nCoV since the virus is vulnerable to oxidation and therefore only the oxidative agents above-mentioned can kill the virus.
- Use rubber dam so as to isolate and maintain a dry field with minimum exposure to saliva, blood or droplet contaminated aerosol or splash. Studies have shown that application of a rubber dam could decrease the airborne particles by 70% in the operational filed.
- Use high-volume suction in addition to rubber dam to reduce aerosol and spatter from the operating site.
- Implement four-handed dentistry, i.e two hands from the dentist and two hands from the dental assistant. This helps to achieve a standard high quality infection control procedure with proper transportation of the sterilised instruments from the assistant to the operator without contamination.
- Use anti-retraction dental handpiece as much as possible to prevent the suck-back/backflow of microbes from the oral cavity through the anti-retraction valves and reduce chances of cross infection.
- Prefer extra-oral radiographs (OPG & CBCT) over intra-oral radiographs (IOPA) in this pandemic period, since intra-oral radiographs can induce saliva secretion and coughing that can be a transmission route for the 2019-nCoV.
- Proper sterilization, cleaning & storage of the armamentarium following treatment of each patient is mandatory.
- Maintain disinfection of the clinic settings by cleaning the tables, chairs, handles of the doors and floors quite often with disinfectants like isopropyl alcohol or 1% sodium hypochlorite & always keep the environment clean.
- Medical waste management should be done correctly. Yellow coloured double layered medical waste package bags must be used to dispose infectious medical waste items.
- Place informative visual patient awareness posters, signboards & flyers at the entrance & patient waiting area on COVID-19 & instructions on respiratory hygiene, hand hygiene and cough etiquette. Instructions should include the technique of handwashing with soap and water & handrubbing with sanitizers insisting how and when to do it. It must also include techniques to cover the mouth and nose while coughing/sneezing with tissue or flexed elbow & proper disposal of tissues with such contaminants.
- Provide a alcohol based hand sanitizer at the entry of your clinic and make handwashing mandatory for all patients & visitors. Also give face masks to the patients while they wait outside.
- Maintain social distancing of minimum 1-metre between all patients and accordingly modify existing patient seating arrangement in the waiting area.
- Number of visitors with the patient must not be more than one.
- Install physical barriers to lessen close contact with patients at the waiting area.
- Try to maintain natural and good ventilation by opening the doors and windows if possible.
- Identify & isolate suspected cases promptly.
The whole world is fighting with a common enemy- The novel coronavirus, and for a common purpose-Life. The impact of COVID-19 pandemic has really shocked the world. Dentistry will not be the same anymore and it will be more challenging in the coming days. We have to be well prepared from the lessons nature has taught us during this outbreak. We must rethink and restart from where we left but this time with more precautions to face the challenge and at the same time we must remember the golden words ‘The only thing we have to fear is fear itself’.
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