Asok, Srivastava, Tandon, Mahajan, Sonal, and Kaur: Dental setup in the covid-ified era – A review


“The measure of intelligence is the ability to change”- this famous quote by Albert Einstein is the rule for the present era. With the emergence of the COVID-19, dentists face a herculean task of upgrading their dental office by means of incorporating a wide range of measures to enhance the hygiene of the dental office, thereby creating a better clean and safe environment for dental practice. Coronaviruses belong to the family of Coronaviridae, of the order Nidovirales, comprising large, single, plus-stranded RNA as their genome. Coronaviruses have traditionally been associated with mild upper respiratory tract infections throughout the world. In the fall of 2002, a new coronavirus emerged in in Asia causing severe viral pneumonia, i.e., severe acute respiratory syndrome (SARS).1 Middle East respiratory syndrome (MERS) is a new human disease first reported from Saudi Arabia in September, 2012, after identification of a novel coronavirus (CoV) from a male Saudi Arabian patient who died from severe respiratory illness. The virus was designated MERS-CoV.2 Last year, in late December a pneumonia outbreak emerged in the city of Wuhan, China which spread very rapidly through the city following which WHO declared a public emergency worldwide on January 30, 2020. The typical clinical symptoms of the patients who suffered from the novel viral pneumonia were fever, cough, and myalgia or fatigue with abnormal chest CT, and the less common symptoms were sputum production, headache, hemoptysis, and diarrhea.3 The infectious agent of this viral pneumonia happening in Wuhan was finally identified as a novel coronavirus (2019-nCOV), the 7th member of the family of coronaviruses that infect humans.4 On 11th February 2020, WHO named the novel viral pneumonia as “Corona Virus Disease (COVID19)”, while the international Committee on Taxonomy of Viruses (ICTV) suggested this novel coronavirus name as “SARSCoV- 2” relating to the phylogenetic and taxonomic analysis of this novel coronavirus.5

Mode of Transmission

The common transmission routes of novel coronavirus include direct transmission like cough, sneeze, and droplet inhalation transmission and contact transmission contact with oral, nasal, and eye mucous membranes.6 In addition, studies have shown that respiratory viruses can be transmitted from person to person through direct or indirect contact, or through coarse or small droplets, and 2019-nCoV can also be transmitted directly or indirectly through saliva. Notably, a report of one case of 2019-nCoV infection in Germany indicates that transmission of the virus may also occur through contact with asymptomatic patients.7

It has been reported by King et al. that after ultrasonic scaling, bacteria could be recovered 6 inches from the mouth of the patient and that the number of colony forming units was significantly reduced when an aerosol reduction device was used during scaling.8 Live viruses (COVID-19) were isolated from the saliva.9 Hence, healthcare workers particularly the dental professionals are at more risk. Considering that numerous kinds of dental equipments that are used in the clinical practice in the form of handpieces, air-water syringes and ultrasonic scalers considerable amounts of aerosols are produced. Hence, the potential for the spread of infections from patients to dentists or dental assistants is high.10

Consequently, the air in dental clinics is likely to be contaminated with several microorganisms to which workers are potentially exposed. Because of the high concentration of bacteria in the oral cavity (nearly of 1.0 E+07–1.0 E+08 colony forming units (CFU)/mL of saliva) and due to concerns of cross contamination between dentists and patients, oral bacteria have been identified as components of dental bioaerosols.11

Figure 1

Treatment protocols during the pandemic

Setup of Dental Office

Patient awareness, education and co-operation play a major role in effective implementation of any control measures in a dental clinic. Hence in the wake of the Covid-19 pandemic, the role of the front office and the reception staff assumes a very significant place and forms the first line of defence. This is also the stage where the patient screening is done.

Note on appoinment and scheduling of patients

Patient should be instructed to take an appointment over the phone, if possible, through video calling, which helps in tele-screening. Patients shall be advised to install the “Aarogya Setu” app in their phones to track their contact history with Covid positive individuals. People who have a travel history or relevant respiratory symptoms should be urged to stay at home and do tele-consultation till the stipulated period or symptoms subside. Similarly, tele-consultations should be done for elderly people and vulnerable group. There should be a policy for walk-in patients in case of an emergency, based on the needs and capabilities of the clinic. There should be a minimum of 15 minutes scheduled between appointments to allow proper disinfection measures. Patients should be requested to wait in their vehicles or any appropriate area for observing social distancing norms in case they arrive early.

Immunisation to the personnel

Ideally every clinical staff should be adequately immunised. The vaccines recommended are BCG, DT, HBV.

Front – room setup

Role of reception staff

  1. The front office/reception staff should be well trained by the management and made aware of the Covid-19 precautionary measures.

  2. The front office staff should always wear 3-ply masks, gloves, when they are in the reception area.

  3. Should wear separate foot wear inside the clinic. It is recommended to sprinkle 1% Bleaching solution on the floor mat / carpet or spread a cloth soaked in 1% bleaching solution to disinfect the feet of patients.

  4. Should instruct the patients and bystanders to wash their hands with soap and water for 20secs before being seated in the clinic.

  5. Should check the temperature of patients using a non-contact infrared scanner thermometer. Treatment for a patient with a measured temperature ≥38 C° (100.4° F) should be deferred.

  6. They should open the doors for the patients to enter the operatory to minimise contamination.

  7. Importance of hand hygiene, social distancing, unnecessarily touching MEN (mouth, eyes, nose) or the T-zone on the face, spitting and putting fingers inside the mouth.

  8. Should categorize the patients after having proper communication with the patient. (Figure 2)

Figure 2

Categorization of the patients

Waiting area setup

  1. A hand wash facility conveniently placed outside the clinic for the patients as soon as they arrive. A poster depicting the WHO recommended hand wash techniques to be displayed in the wash area.

  2. Provide Hand sanitisers in the waiting area.

  3. Remove all articles like newspapers, magazines, print material, flower vases, showcase artefacts, toys, carpets etc from the waiting area to reduce areas that are not amenable for disinfection.

  4. The seating pattern in the waiting area should be arranged in a manner to ensure physical distancing.

  5. The waiting area should be mopped and disinfected, every two hours, using 1% NaOCl solution.

  6. Audio/visual alerts can also be used in addition to educate and motivate the patients.

Consultation room setup

  1. Restrict entry of bystanders and clinical staff into this area during procedures.

  2. Keep separate dental chairs or cubicles for examination/minimally invasive procedures and for aerosol generating procedures.

  3. Disposable bins should be placed within this area so that contaminated waste can be sorted in this same area.

  4. Keep an alcohol-based sanitizer (>70%) on the side of the dental chair. Soap/Hypochlorite solution should be placed within the area for immediate immersion of instruments post use.

  5. A minimum of 6 ft distance around the dental chair where aerosol generating procedures are done should be designated as a red (danger) zone. The red zone (danger) area should be cleaned, wet mopped and meticulously disinfected using 1% NaOCl solution after every procedure

  6. Use of air-conditioners is not recommended and natural ventilation to be promoted during aerosol generating procedures.

  7. If Air conditioners are used air purifiers with High Efficiency Particulate Air (HEPA) filters and other purifying systems are recommended.

  8. Position of dentist at 11 o’ clock or 12 o’clock and never at an 8 o’ clock position to minimise direct contamination and avoid splatter trajectory.

  9. Time gap of minimum 55 minutes should be kept between appointments.

  10. Waiting period of 20 minutes post procedure for aerosol to settle.

  11. Proper cleaning and disinfection of the red zone and the machineries (approx. 10 mins).

  12. Proper sterilization of instruments (approx. 20 mins)

  13. Simultaneous fumigation with silver nitrate and hydrogen peroxide. Fumigating time is 15 min, after fogging we can use the room within 15 min.

  14. Proper management of PPE equipment (approx. 5 mins).

Personel protective equipment (Figure 3)

  1. 3-ply masks and a pair of gloves should be worn by dental practitioners always inside the clinic.

  2. N95 masks, head cap, goggles or face-shield, have to be worn by practitioners while doing procedures.

  3. A surgical glove worn above the examination gloves is advisable (Double gloves).

  4. A gown with long sleeves, Fluid resistant material (Ideally of 70 gsm or above.

  5. If reusable, the material should be certified by a recognised body like South India Textile Research Association (SITRA), Defence Research and Development Organization (DRDO) as recommended by Government of India to ensure that the barrier properties are retained even after wash/disinfection) is recommended for additional protection.

3 Tests to check the quality of 3 ply-masks before purchasing – this is necessary because of the duplicate products that are released over this period of time.

Figure 3


Visual test (Figure 4)

  1. Cut open the mask and you should see a very obvious 3-layers.

  2. Translucent piece (top), White piece (middle), and the coloured piece (Green, Blue, or even White).

Figure 4

Layers of 3-ply mask

Table 1

WHO Classification ofhealth care waste12

Waste categories Description
Infectious waste Waste suspected to contain pathogens; e.g., laboratory cultures, tissues, swabs, materials or equipment that have been in contact with infected patients, excreta, etc
Pathological waste Human tissues or fluids; e.g., body parts, blood and other body fluids, fetuses, etc
Sharps Sharp waste; e.g., needles, scalpels, blades, knives, infusion sets, broken glass
Pharmaceutical waste Waste containing pharmaceuticals; e.g., pharmaceuticals that are expired or no longer needed, items contaminated by or containing pharmaceutics (bottles, boxes)
Genotoxic waste Waste containing substances with genotoxic properties; e.g., cytotoxic drugs (cancer drugs), genotoxic chemicals
Chemical Waste Waste containing chemical substances; e.g., laboratory reagents, film developer, fixer, disinfectants that are expired or no longer needed, solvents
Wastes with high content of heavy metals Batteries, broken thermometers, blood pressure gauges, etc
Pressurized containers Gas cylinders, gas cartridges, aerosol Cans
Radioactive Waste Waste containing radioactive substances; e.g., unused liquids from radiotherapy or laboratory research, contaminated glassware, packages or absorbent paper, urine and excreta from patients treated or tested with unsealed radionuclides, sealed sources

Table 2

Theproposed simplified biomedical waste segregation scheme for dental clinics13

Red bag Yellow bag Blue bag Black carboy
Disposable injection syringes, IV set without needleSaline bottlesPlastic suction tipsToothbrushes, denture brushesDisposable plastic/fiber instrumentsPlastic/rubber tubesRubber lids of any vial Used plastic drapes Anything contaminated by blood or body fluids Body parts Any item which have been in contact with the patient Bandages, cotton Teeth (with/withoutfillings but without amalgam fillings)Dressings and swabsDisposables such as gloves,aprons,masks,drapes, contaminated wipes, throat packs Discarded crowns, bridges and cast partial denturesWaxes, gutta purcha points, absorbent pointsDisposable impression trays with impression material Acrylic partial dentures, complete dentures, denture teeth Plaster/ stone castsCheek retractors, tongue depressors, wedgesRubber dam material Plastic X-ray pouches(outer covering)Catheters(after draining)Unwanted laboratory specimensSuture materials without needle Glass bottlesBroken bottles Discarded medicines Antiseptics, disinfectants (not contaminated by body fluids)Used or unused drug vialsCartridges and ampoules Used or unuseed sharpsNeedles without syringes Scalpel blades Metal objects Metal matrix bands Broken metal instrument tipsBurs Endodontic files, broaches, reamers, spreaders,silver pointsOrthodontic metal brackets,wires,bandsSuture needles Broken/discarded ultrasonic tips Metallic bars, clasps from partial dentures Metal lids of vials All metalic dental implants related material

Water test

  1. The outer layer is designed to be waterproof.

  2. Fold the mask such that the outer side forms a funnel and pour some water into it. The mask should be holding up the water properly.

Fire test

  1. The middle layer is a filter, not a piece of paper. Therefore, if you were to light it with a flame, it WILL NOT catch fire.

Figure 5

Sequence of wearing PPE

Sequence of wearing PPE – Centre of Disease Control Guidelines (Figure 5)


  1. Fully cover torso from neck to knees, arms to end of wrists, and wrap around the back.

  2. Fasten in back of neck and waist.

Figure 6

Sequence of removing PPE

Mask or respirator

  1. Secure ties or elastic bands at middle of head and neck.

  2. Fit flexible band to nose bridge.

  3. Fit snug to face and below chin.

  4. Fit-check respirator.

Goggles or face shield


Sequence of removal of PPE – Centre of Disease Control Guidelines (Figure 6)

  1. Outer Gloves (assume outside of glove is contaminated.

  2. Gown (assume gown/apron front and sleeves are contaminated.

  3. Goggles or face shield (assume outside is contaminated.

  4. Mask (assume front is contaminated.

  5. Remove the inner gloves.

  6. Perform hand hygiene.

Waste Management

As directed by Central Pollution Control Board (CPCB), the guidelines for PPE are as follows

  1. Goggles, face-shield, splash proof apron, plastic coverall, hazmat suit, nitrile gloves – RED BAG.

  2. Masks (including triple layer mask, N95 mask, etc.), head cover/cap, shoe-cover, disposable linen gown, non-plastic or semi-plastic coverall – YELLOW BAG.

Summarisation of waste management in 2 tables.


The working area of a dentist, the dental office, is different from other health proffessionals in that there is a closer doctor patient interaction and the chances of infection spread is high. In these dark times, especially with every patient being a potential carrier for the novel coronavirus, proper precautions if not taken can result in cross contamination. So a proper maintanance of hygiene, a strict protocol along with great caution is the way to go forward in this proffession.

Source of Funding


Conflict of Interest




C B Cunha S M Opal Middle East respiratory syndrome (MERS)Virulence2014566504


A Assiri Epidemiological, demographic, and clinical characteristics of 47 cases of Middle East respiratory syndrome coronavirus disease from Saudi Arabia: a descriptive studyLancet Infect Dis201313975261


P Coulthard Dentistry and coronavirus (COVID-19) - moral decision-makingBr Dent J202022875035


P Zhou X L Yang X G Wang B Hu L Zhang W Zhang A pneumonia outbreak associated with a new coronavirus of probable bat originNature202057977982703


A E Gorbalenya S C Baker R S Baric R J de Groot C Drosten A A Gulyaeva Severe acute respiratory syndrome-related coronavirus: the species and its viruses—a statement of the Coronavirus Study Group2020202010.1101/2020.02.07.937862


C W Lu X F Liu Z F Jia 2019-nCoV transmission through the ocular surface must not be ignoredLancet202010.1016/S0140-6736(20)30313-5


X Peng X Xu Y Li L Cheng X Zhou B Ren Transmission routes of 2019-nCoV and controls in dental practiceInt J Oral Sci202012110.1038/s41368-020-0075-9


J B Barnes S K Harrel F Rivera-Hidalgo Blood Contamination of the Aerosols Produced by In Vivo Use of Ultrasonic SealersJ Periodontol19986944348


K K W To O T Y Tsang C C Y Yip K H Chan T C Wu J M C Chan Consistent detection of 2019 novel coronavirus in salivaClin Infect Dis202071158413


M S Ahmed D Barman Girish R E Devi S Kazi S Bhure Dental considerations in Corona Virus Infections: First review in literatureJ Adv Med Dent Scie Res2020821003


S Dutil A Mériaux M-C de Latrémoille L Lazure J Barbeau C Duchaine Measurement of Airborne Bacteria and Endotoxin Generated During Dental CleaningJ Occup Environ Hyg20086212130


A Pruss E Cirouit P Rushbrook Safe management of wastes from health care activities1999


O N Baghele M O Baghele A A Deshpande J P Deshpande S Phadke A simplified model for biomedical waste management in dental practices - A pilot project at Thane, IndiaEur J Gen Dent20132323540


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