International Journal of Academic Medicine

: 2020  |  Volume : 6  |  Issue : 2  |  Page : 56--63

Novel coronavirus infection and periodontal clinic: Are we prepared?

Malvika Singh 
 Assistant Professor, Department of Periodontics and Oral Implantology, Institute of Dental Sciences, Jammu, Jammu and Kashmir, India

Correspondence Address:
Dr. Malvika Singh
Department of Periodontics and Oral Implantology, Institute of Dental Sciences, Jammu, Jammu and Kashmir


Coronavirus infection has become a matter of serious concern for the world these days. Signs and symptoms include dry cough, fatigue, coughing sputum, and shortness of breath. Due to the continuous production of aerosol in periodontal clinics and because of the fact that the virus remains alive for 12 h, periodontists are highly susceptibility risk for the same. This article is an attempt to throw light on coronavirus infection and enumerating certain preventive measures to be taken in a periodontal setup for the prevention of the same. The following core competencies are addressed in this article: Medical knowledge, Patient care, Practice-based learning, Systems-based practice.

How to cite this article:
Singh M. Novel coronavirus infection and periodontal clinic: Are we prepared?.Int J Acad Med 2020;6:56-63

How to cite this URL:
Singh M. Novel coronavirus infection and periodontal clinic: Are we prepared?. Int J Acad Med [serial online] 2020 [cited 2020 Aug 13 ];6:56-63
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Coronavirus infection was identified by Chinese government in China's Wuhan district on January 7, 2020,[1] and declared as a pandemic by the World Health Organization on March 11, 2020.[2] As on April 13, 2020, this viral infection has been recognized in over 158 countries worldwide claiming 105,952 lives and infecting 1,696,588 confirmed people worldwide.[3] Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),[4] also known by the provisional name 2019 novel coronavirus (2019-nCoV),[5] is a positive-sense, single-stranded RNA virus that has become center of attention and concern for world these days. The virus primarily spreads between people via respiratory droplets from coughing.[6] The time between exposure and symptom onset ranges from 2 to 14 days,[7] which includes fever, dry cough, and shortness of breath,[8] sometimes leading to pneumonia, acute respiratory distress syndrome, and death (if left untreated). Due to the characteristics of dental settings, the risk of cross infection may be high between dental practitioners and patients. In spite of relentless research over pharmaceutical treatment being done every minute, there is currently no vaccine or specific antiviral treatment, which makes this infection even more scary and serious. However, efforts aiming toward managing symptoms and supportive therapy have been widely recommended. This article is based on the relevant guidelines given by various reputed organizations and my experience which deals with introduction of the essential knowledge about COVID-19 and nosocomial infection in periodontal settings, providing recommended management protocols for dental practitioners in (potentially) affected areas.

 History and Epidemiology

On December 31, 2019, a cluster of pneumonia cases of unknown cause were reported by health authorities in Wuhan, the capital of Hubei province, China.[8] These cases mostly had links to the Huanan Seafood Wholesale Market, which also sold live animals; consequently, the virus is thought to have a zoonotic origin.[9] The virus that caused the outbreak is known as SARS-Co-2, a new virus that is closely related to bat coronaviruses [10] and SARS-CoV.[11] It is believed that the virus possibly originated in bats of the Rhinolophus genus. The first case of novel coronavirus in India was detected on January 30, 2020,[12] and as on April 13, 2020, 1,696,588 confirmed cases have been reported in over 158 countries and territories, out of which 105,952 people have lost their lives and over 73,000 have recovered from this infection.[3]

 Phylogenetics and Taxonomy

SARS-CoV-2 belongs to the broad family of viruses known as coronaviruses. It is a positive-sense, single-stranded RNA (+ssRNA) virus and a member of the subgenus Sarbecovirus (beta-CoV lineage-B).[13] Its RNA sequence is approximately 30,000 bases in length. The unique quality among known Betacoronaviruses is that it incorporates a polybasic cleavage site, which increases its pathogenicity and transmissibility in other viruses.[14] On February 11, 2020, the International Committee on Taxonomy of Viruses identified 2019-nCoV as a strain of severe acute respiratory syndrome-related coronavirus.[4]

 Structural Biology and Virology

Each SARS-CoV-2 virion is approximately 50–200 nm in diameter. It has four structural proteins, known as the S (spike), E (envelope), M (membrane), and N (nucleocapsid) proteins; the N protein holds the RNA genome, and the S, E, and M proteins together create the viral envelope. SARS CoV-2 virus has spikes on the outer edge that resembles the shape of a crown, thus giving the disease its characteristic name. The spike protein is responsible for allowing the virus to attach to the membrane of a host cell.[15] Protein modeling experiments on the spike protein of the virus soon suggested that SARS-CoV-2 has sufficient affinity to the angiotensin-converting enzyme 2 (ACE2) receptors of human cells to use them as a mechanism of cell entry.[16]

Initial spike protein priming by transmembrane protease, serine 2 (TMPRSS2) is essential for the entry of SARS-CoV-2.[17] After the virus spike protein has attached to the ACE2 molecule of its target cell, the spike is cut open by another protein on the cell exterior, protease TMPRSS2, exposing a fusion peptide. The virus then releases RNA into the cell, forcing the cell to produce copies of the virus that are disseminated to infect more cells.[18] SARS-CoV-2 produces at least three virulence factors that promote shedding of new virions from host cells and inhibit immune response.[15]

 Clinical Manifestations

Case definition:[3] According to the WHO

Suspect case is defined as:

(a) A patient with acute respiratory illness (fever and at least one sign/symptom of respiratory disease, e.g., cough and shortness of breath) AND a history of travel to or residence in a location reporting community transmission of COVID-19 disease during the 14 days prior to symptom onset.

OR (b) A patient with any acute respiratory illness AND having been in contact with a confirmed or probable COVID-19 case (see definition of contact) in the last 14 days prior to symptom onset

OR (c) A patient with severe acute respiratory illness (fever and at least one sign/symptom of respiratory disease, e.g., cough and shortness of breath AND requiring hospitalization) AND in the absence of an alternative diagnosis that fully explains the clinical presentation.

Probable case is defined as:

(a) A suspect case for whom testing for the COVID-19 virus is inconclusive (Inconclusive being the result of the test reported by the laboratory)

OR (b) A suspect case for whom testing could not be performed for any reason.

Confirmed case is defined as a person with laboratory confirmation of COVID-19 infection, irrespective of clinical signs and symptoms.


A contact defined as a person who experienced any one of the following exposures during the 2 days before and the 14 days after the onset of symptoms of a probable or confirmed case: (1) face-to-face contact with a probable or confirmed case within 1 meter and for more than 15 min; (2) direct physical contact with a probable or confirmed case; and (3) direct care for a patient with probable or confirmed COVID-19 disease without using proper personal protective equipment or other situations as indicated by local risk assessments.

Signs and symptoms

The most commonly reported clinical symptoms in laboratory-confirmed cases are fever (87.9%), followed by dry cough (67.7%) and fatigue (38.1%), whereas the less common symptoms include coughing up sputum (33.4%), shortness of breath (18.6%), pain in muscles or joints (14.8%), sore throat (13.9%), headache (13.6%), chills (11.4%), nausea or vomiting (5%), nasal congestion (4.8%), diarrhea (3.7%), hemoptysis (0.9%), and conjunctival congestion (0.8%). However, in severe form of disease, patients may experience high fever, decreased white blood count, and kidney failure.[19] About 80% of reported cases in China had mild-to-moderate disease (including nonpneumonia and pneumonia cases), 13.8% had severe disease, and 6.1% were critical (respiratory failure, septic shock, and/or multiple organ dysfunction/failure).

Incubation period

Current estimates suggest a median incubation period from 5 to 6 days for COVID-19, with a range from 1 to up to 14 days. A recent modeling study confirmed that it remains prudent to consider the incubation period of at least 14 days.[20]

Case fatality

Based on a large dataset from cases in China, the overall case fatality risk (CFR) among laboratory-confirmed cases was higher in the early stages of the outbreak (17.3% for cases with symptom onset from 1 to 10 January) and has reduced over time to 0.7% for patients with symptom onset after 1 February.[21] In data on diagnosed COVID-19 cases in China, Italy, and South Korea, the overall CFR was 2.3%, 2.8%, and 0.5%, respectively, and increased with age in all settings, with the highest CRF among people over 80 years of age (14.8%, 8.2%, and 3.7%, respectively).[22],[23],[24]

Viral shedding

Over the course of the infection, the virus has been identified in respiratory tract specimens 1–2 days before the onset of symptoms and it can persist for 7–12 days in moderate cases and up to 2 weeks in severe cases.[25] In feces, viral RNA has been detected from day 5 after onset and up to 4–5 weeks in moderate cases. The virus has been detected also in whole blood,[26] serum,[27] saliva,[28] and urine. Prolonged viral RNA shedding has been reported from nasopharyngeal swabs, up to 37 days among adult patients [29] and in feces, for more than 1 month after infection in pediatric patients. Based on Chinese data, the international WHO mission report indicates that up to 75% of initially asymptomatic cases progress to clinical disease, making the true asymptomatic infection rather rare (estimated at 1%–3%).[21] Transmission in pre-symptomatic stage of infection: In addition to case reports, pre-symptomatic transmission has been inferred through modeling, and the proportion of presymptomatic transmission was estimated to be around 48% and 62%.[30]

Vulnerable groups

Population groups that have been more frequently reported having severe disease and death include people above 60 years of age; males; and people with underlying conditions such as hypertension, diabetes, cardiovascular disease, chronic respiratory disease, and cancer.[21],[31] Higher ACE II gene expression may be linked to higher susceptibility to SARS-CoV-2. It has been shown that ACE II expression in lung tissues increases with age, tobacco use, and some hypertensive treatments. These observations might explain the vulnerability of older people, tobacco users/smokers, and those with hypertension; they also highlight the importance of identifying smokers as a potential vulnerable group for COVID-19.[32],[33] There is limited scientific evidence on the severity of illness among pregnant women with COVID-19. Currently, available information indicates that children are as likely to be infected as adults; however, they experience mild clinical manifestations.[22],[34]

People at high risk of infection

Current observations suggest that people of all ages are generally susceptible to this new infectious disease. However, those who are in close contact with patients with symptomatic and asymptomatic COVID-19, including health-care workers and other patients in the hospital, are at higher risk of SARS-CoV-2 infection.[35]


The primary mode of transmission is via respiratory droplets that people exhale, for example, when coughing or sneezing.[6] Droplets only stay suspended in the air for a short time, but may stay viable and contagious on a metal, glass, or plastic surface.[36] The WHO has stated that the risk of spread from someone without symptoms is very low and that fecal transmission is low.[6] The basic reproduction number of the virus (the average number of people an infected person is likely to infect) ranges from 2.13[30] to 4.82.[37]


Diagnosis of COVID-19 can be done through viral testing and computed tomography (CT) imaging. Infection by the virus can be provisionally diagnosed on the basis of symptoms, though confirmation is ultimately by real-time reverse transcription polymerase chain reaction (rRT-PCR) of infected secretions (71% sensitivity) and CT imaging (98% sensitivity).[38]

Viral testing

According to the WHO, rRT-PCR is used as the method for viral testing of COVID-19.[39] With a sensitivity of 71%, the test can be done on respiratory or blood samples and the results are generally available within a few hours to days.


Characteristic imaging features on radiographs and CT have been described in a limited case series. Although it is 98% sensitive, due to overlap with other infections such as adenovirus, imaging without confirmation by PCR is of limited use in identifying COVID-19.[40]

 Guidelines in Periodontal Setup

Risk of nosocomial infection in periodontal settings

Dental OPD or clinics often receive a whole bunch of patients belonging to different age groups, habits, and strata of society. Some of them often belonging to vulnerable groups as discussed above. The patients who cough, sneeze, or receive dental treatment including the use of a high-speed handpiece or ultrasonic instruments make their secretions, saliva, or blood aerosolize to the surroundings, contaminating dental apparatus with various pathogenic microorganisms or become exposed to a contaminated clinic environment. Thereafter, infections can occur to clinicians, their support staff, and other patients through the puncture of sharp instruments or direct contact between mucous membranes and contaminated hands.[41] Due to the unique characteristics of dental procedures where a large number of droplets and aerosols could be generated, the standard protective measures in daily clinical work are not effective enough to prevent the spread of COVID-19, especially when patients are in the incubation period, are unaware they are infected, or choose to conceal their infection. Diagrammatic representation of personal protective measure to be worn by both dental professional and personnel while performing any dental procedure has been shown in [Figure 1].{Figure 1}

Recommendations for Periodontal (dental) Practice

Interim guidance on infection prevention and control during health care is recommended when COVID-19 infection is suspected.[1] Up to now, there has been no consensus on the provision of dental services during the epidemic of COVID-19. On the basis of my experience and relevant guidelines given by the Dental Council of India, periodontists and other clinicians performing a periodontal procedure should take strict personal protection measures and avoid or minimize operations that can produce droplets or aerosols. The following guidelines are suggested:[42],[43]

All clinicians should be well versed and updated with all information about coronavirus infection and should assure that their support staff also know the sameEvaluation of patients: During the outbreak of COVID-19, dental clinics are recommended to establish precheck triages to measure and record the temperature of every staff and patient as a routine procedure and make it sure that patient is not masking its temperature by taking over the counter drugs such as paracetamol before visiting dental clinicPrecheck staff should ask patients questions about the health status and history of contact or travel and should immediately inform police and other concerned administrative authorities if found suspicious about the samePatients with fever should be registered and referred to designated hospitals. If a patient has been to epidemic regions within the past 14 days, quarantine for at least 14 days is suggested after informing police and other concerned administrative authoritiesEvery patient and accompanying patient who enters and exits dental clinic should be provided with mouth masks and their hand should be sterilized using hand sanitizersThe waiting room should have hand sanitizers and pictorial information in the form of charts or digital information in the form of bulletin boards regarding COVID-19 should be displayedEach seat in the waiting area should have a minimum distance of 1 meter (3 feet) as a preventive social distancing measure.[1] All patients including their attendants should be counseled by the clinicians regarding COVID-19 and the need to stay home for quarantinedThe waiting room/clinic including handles and doors as well as dental chairs and other surfaces should be wiped several times in a day with alcohol-based disinfectantOral examination: Preoperative antimicrobial mouth rinse could reduce the number of microbes in the oral cavity. Procedures that are likely to induce coughing should be avoided (if possible) or performed cautiously. Aerosol-generating procedures, such as the use of a 3-way syringe, should be minimized as much as possible. Intraoral X-ray examination is the most common radiographic technique in dental imaging; however, it can stimulate saliva secretion and coughing. Therefore, extraoral dental radiographies, such as panoramic radiography and cone-beam CT, are appropriate alternatives during the outbreak of COVID-19Thorough medical and travel history of each patient should be recorded before any clinical procedurePatients should be scrubbed with isopropyl alcohol extraorallyPreprocedural mouth rinse with povidone iodine is recommendedAll dentists and support staff should wash their hands thoroughly with soap and water and follow up with alcohol-based sanitizers before and after every patientSurgical scrubbing of hands is recommendedStaff and doctors should avoid touching their face, especially ear, nose, and mouthWearing of N95 or at least 3-Ply masks and suitable head caps, protective eye wear, and/or face shield is recommendedTreatment of a periodontal patient:

Phase 0: This phase called as the “emergency phase” involves procedures that require immediate attention by the clinician. Thus, patients having pain due to exposure of pulp, abscess, or extraction cases should be treated (in case of periodontal abscess) or referred to other departments (for root canal treatment or extraction accordingly)Phase I: This phase is known as “nonsurgical phase” and involves scaling and/or root planning which involves usage of ultrasonic machines which produce aerosol. Since there has been enough evidence supporting the spread of COVID-19 infection through aerosol production, patients having mild and moderate form of gingivitis and periodontitis should be avoided or minimized for ultrasonic scaling. Scaling should be done in cases of severe form of gingivitis or periodontitis with the use of saliva ejectors with low or high volume reducing the production of droplets and aerosolsPhase II: This phase is also known as “surgical phase” and deals with all the surgeries of periodontium (gingiva and alveolar bone). Periodontal emergencies such as pericoronitis or in some cases pregnancy tumor can occur and exacerbate in a short period and therefore need immediate treatment with continuous use of high-volume saliva ejectors. The other surgical procedures such as flap surgeries, all mucogingival surgeries, perioplastic surgeries, and dental implant surgeries should be postponed for further visitsPhase III: This phase is known as “restorative phase” and deals with interdisciplinary approach of restoring carious and missing tooth in patients after undergoing oral prophylaxis. Patients falling under this category need not to be treated immediately and can be given appointments for the samePhase IV – Supportive phase: Oral hygiene instructions and diet modifications should be given to patients explaining their importance and the same should be recalled for subsequent visits accordingly. Patients belonging to vulnerability group, i.e., old age patients, smokers, and diabetic patients, should be counseled more about this disease and educated to lay more emphasis of improving their periodontal as well as overall health. Smokers should be motivated more for smoking cessation programmers.

All masks, gloves, head caps to be disposed as per waste management protocolFumigation of clinicals periodically is recommendedPatients could be treated in an isolated and well-ventilated room or negatively pressured rooms if available for suspected cases with COVID-19In areas where COVID-19 spreads, nonemergency dental practices should be postponed.[44]

It was reported that dental practice should be postponed at least 1 month for convalescing patients with SARS. It is unknown yet whether the same suggestion should be recommended for patients with COVID-19. Since its outbreak, in most cities of the mainland of China, only dental emergency cases have been treated when strict implementation of infection prevention and control measures is recommended. Routine dental practices have been suspended until further notification according to the situation of epidemics.[45]

Recent trends

Coronavirus infection continues to spread around the world, but till date, the drug or vaccine to kill virus or protect against it has not been formulated. However, the research is happening at breakneck speed and there are more than 20 vaccines in development. One of them has begun human trials after unusually sipping any animal research because that would delay results by another 1 year. Other scientists are at the animal research stage and hope to get the results of human trials later in the year. According to the World Health Organization, the only antiretroviral drug right now that seems to have worked in some patients is remdesivir.[46] There has also much interest in an old and cheap antimalarial drug called chloroquine since some laboratory tests have shown to kill viruses, but once again results in patients are anticipated. Recently, scientists have found the effectiveness of FDA-approved antiviral drug called ivermectin to inhibit 5000-fold reduction on virus in cell culture. It is the same drug that was found useful in the treatment of HIV, dengue, influenza, and zika virus. Although it requires more clinical trials, as of now, this drug perhaps seems to be a ray of hope in the treatment of this infection as well.[47]


Since there is currently no vaccine or specific antiviral treatment, ongoing rigorous research is giving us a ray of hope and paving the way for development of a vaccine in near future. Till the time we get any good news in the form of discovery of drug or vaccine, efforts should be aimed at managing symptoms and supportive therapy, including washing hands; using an alcohol-based hand sanitizer with at least 60% alcohol by volume when soap and water are not readily available when appropriate; avoiding touching the eyes, nose, or mouth with unwashed hands; coughing/sneezing into a tissue and putting the tissue directly into a dustbin; and (for those who may already have the infection) wearing a surgical mask in public. The guidelines when treating a patient in periodontal setup are highly recommended, so safety of clinician as well as patient is maintained and the infection is not spread further.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

Ethical conduct of research

For writing this article, the authors utilized data from reputed organizations such as World Health Organization, Ministry of Health and Welfare, Govt. of India and Centers of Disease Control and Prevention U.S Department of Health and Human Services. Also, Medline and PubMed databases were searched under the following key terms: Coronavirus infection, periodontal emergencies, periodontal clinics, treatment and prevention. Only highly relevant articles from manual and electronic databases were selected for the present review. Applicable EQUATOR network ( guidelines were followed.


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