Introduction
The various epidemics occurred in past like H1N1, influenza, Ebola, SARS, Nipha and Zika had influenced the world with greater intensity were handled efficiently by the cautious scientific approaches.1 On the day of 8th January, 2020 the official declaration of novel corona virus was made as COVID-19 by Center for Disease Control and prevention of China.2 On the day of 30th January 2020 worldwide transmission of corona virus was reported by World Health Organization (WHO) as situation of emergency related to public health.3 Previously corona virus was termed 2019-nCov on official basis as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). On the day of 26th February 2020, COVID-19 was established within 34 countries world over along with 80,239 confirmed infected cases and death toll upto 2700.4
The word over spread of this corona virus has posed the greater threat of spread among the oral health professionals and patients with higher risk of contracting infection or carrying disease in the community. As per the regulations of ‘occupational safety and health administration’ (OSHA), all dental professionals are categorized in category of very-high risk exposure due to their operational field as oral cavity.5
The most of the dental procedures are aerosol generating as they involve use of rotary hand piece and ultra sonic scalers so the thorough research should to be carried out for the knowledge of transmission of corona virus, clinical characteristic and testing modalities. This article is mainly based upon the researches to be followed for the regulations and recommendations included in the protocol by the dental professionals for preventing spread of corona virus to themselves and their patients.
Etiology of COVID-19
As mentioned in latest studies, related to SARS-CoV and ‘Middle east respiratory syndrome coronavirus’ (MERS-CoV), SARS-CoV-2 type is zoonotic virus with Chinese Horseshoe Bats (Rhinolophus sinicus) with most probably origin from Pangolins as the preferable intermediate host.6, 7
Structural composition
The SARS-CoV-2 is 7th member in coronaviruses group, which infect human beings with similarity to betacoronaviruses, still different from ‘SARS-CoV’ and ‘MERS CoV’. This virus belong to subgenus sarbe-covirus, Orthocoronavirinae subfamily, with Chinese horse-shoe bats as common origin.8 The 2019-nCoV consist of specific structure along with spiked protein in the outer membrane and also possess other components such as polyprotiens, nucleoproteins, 3-chymotrypsin protease, RNA polymerase, helicase, protease similar to papain and other accessory proteins. 8, 9, 10 The binding of corona to host cells receptors is mediated by the S protein. 11, 12 The 4 different amino acid are present in 2019-n Co Vans SARS CoV, whereas 2019-nCoV associate with human ACE-2, similar receptors in SARS CoV which bind to ACE2 receptors of human cells, also in cat, bat and pig; however not associated with cells without angiotensin-converting-enzyme 2.13, 14, 15
Routes of communication
The infections of SARS-CoV-2 mainly transmit by droplets oozed while respiration or with person to person contact hence infection can spread by coughing, sneezing by an infected patient by airborne route to the other non-infected patients in the close vicinity within the radius of approximately 6 feet. 6
According to the researchers of United States fecal-oral route is also the one route of transmission of SARS-CoV-2. 16
Steps of transmission of corona virus (Table 1): 3
Table 1
Incubation period
The average period of 5 to 6 days is considered as incubation period; however it has been estimated to be prolonged up to 14 days at present for keeping patient under medical supervision and quarantine of exposed individuals. 17
Individuals with high risk of infection
It is revealed from the present studies that individuals of all ages are susceptible to these viral diseases. Although, the individuals in contact with COVID-19 affected persons have higher chance of being infected.1
Large number of patients tested positive for COVID-19 have good prognosis, whereas very low patients have reported with critical conditions, specifically involving those who are elderly or with underlying chronic diseases. On the day 1 of month of March 2020 79,968 cases were confirmed positive, 14,475 i.e.18.1% consist of patients with severe illness, and 2873 (3.5%) of deaths were reported in China by World health organization.18
The other complications involved include arrhythmia, nephritis, acute cardiac injury, secondary infection and liver dysfunction.19
Symptoms
The infected patient have clinical symptoms such as dry-cough, fever, muscle pain, other symptoms which may appear include nausea, diarrhea, hyposmia i.e. loss of sense of smell, abnormal taste sensation i.e. dysguesia. 20, 21 Patients undergone chest CT revealed pneumonia bilaterally along with opacity showing ground glass appearance multiple patchy shadows as a familiar pattern. 22 The COVID-19 infected geriatric patients suffering with other underlying diseases like diabetes, hypertension, respiratory diseases, cardiovascular disorders progressively developed ARDS, underwent shock, metabolic and coagulation dysfunction further leading to death. 19
Diagnosis and treatment
Information i.e. travel history to infected areas 14 days prior to symptom origin, radiographic imaging i.e. CT, laboratory tests ‘reverse-transcriptase polymerase chain-reaction’ (RT-PCR) is established upon oro-pharyngeal and naso-pharyngeal swabs as specimens are the basis for diagnosis of COVID-19. 23 Presently the only protocol followed for controlling COVID-19 infection include early-diagnosis, isolation and supportive regime. 24 Some clinical studies revealed medications as interventions include Lopinavir and Remdesivir. 25
Results of coronavirus pandemic on dental practice
Threat of nosocomial infection in dental operatory: The frequent use of rotary instruments like air rotar handpiece and scalers in dental operatory specially in case of infected patient with symptoms of cough and sneeze lead to spread of salivary and blood secretions in form of aerosols in the adjoining areas of the operating field. The machinery and dental equipments become contaminated in such situation and hence infection spread through breach of sharp instruments or directly by intercommunication within the mucosa and the infected hands of the operator.26
Considerations for dental procedures in coronavirus infection period
The dental professionals including dental doctors, hygienists, assistants and other personals should enhance their skills and knowledge concerning disinfection, patient follow up as suggested by the apex bodies time to time. The salivary epithelial cells potentially get infected with SARS-CoV and act as main infection source. 27
The closure of dental practice during lockdowns can however reduce the chance of cross infection but the urgent patients requiring urgent treatment must be provided dental care.
Hence standard instructions regarding dental procedures should be followed world over during COVID-19 pandemic.
Management of dental patients for prevention of nosocomial infection
Dental care can be classified as shown in table 2. According to ADA 28
Table 2
.
Teledentistry and its application in current COVID-19 pandemic
‘Teledentistry (as the part of telehealth system along with telemedicine) is remote facilitating of dental health care, guidance, education or treatment with utilization of information-technology rather than by physical appearance or contact of operator and the patient’. 29
Interactive tracking of the COVID-19 patient can be done as shown in the figure 1Figure 1 . 30
Parts of Teledentistry includes
Telecosultation: In this procedure the patient or the local heath care provider seeks consultation with dental specialist via the telephonic mode. 31
Telediagnosis: This method utilizes the technology for exchanging images and data for proper diagnosis of the oral lesions. 32, 33 The various devices like smart phones, MeMoSA (mobile mouth screening anywhere), Cell scope device, WhatsApp have used for teleconsultation. 34, 35, 36, 37, 38
Teletriage: It involves safe, suitable and timely deposition of symptoms of patient with smart phone by a specialist. It is utilized for remote assessment of children in school and to separate those who require treatment without their unnecessary visit to dental offices. 39
Telemonitoring: This technique reduces the visit of patient to dentist as replaced by virtual visits for consistent assessment of treatment results. 31
Assessment of dental patient: The following Table 3 . Reveals questions asked from patient on arrival to the dental office for patient assessment.
Table 3
Date: Name: Date of birth:
Emergency pharmacological management: The following Table 4. indicates primary and secondary management in emergency conditions during COVID-19 pandemic.
Table 4
Standard precautions to be followed for disease transmission and logistics to be used
Dental professionals should follow standard precautions to protect themselves from COVID infection which includes hand hygiene (hand washing with water and soap upto 20 sec or utilization of hand-sanitizer with composition of 60% alcohol), utilization of PPEs, sharp safety, respiratory hygiene, sterile instruments and equipments, disinfection of the operating fields. Transmission based precaution includes patient isolation, ventilation, use of N-95 masks and deferring of non urgent procedures. Dentist should wear surgical mask, eye wear, face shields, for protection from droplet spattering. Negative – pressure rooms ‘Airborne Infection Isolation Rooms’ (AIIRs) set up should be established for treatment of COVID-19 infected patients in case of dire emergencies. The other additional methods to be followed in dental practice for protection from COVID as precautionary measures include use of .01% NaOCl which inactivates viral agents aspirated via water lines. 46 The filtration of air can be done via high efficiency aerosol arrestor filters establishment in the dental clinics. 47
Conclusion
The main duty of all the dental professionals in COVID-19 pandemic is the protection of themselves and their patients from the transmission of the infection after following all the recommendations and standard guidelines issued by various health authorities time to time, however educating the patient and making the appropriate clinical decisions for patient benefit during this pandemic is a challenging task for all the dental professionals. Our review article will definitely be helpful for the dental clinicians for making appropriate decisions while treating their patients during this COVID-19 pandemic phase.
