Dentistry during the Coronavirus outbreak

Dental and medical clinics have always been highly biohazardous areas where strict practices and procedures must be followed. In recent months, the global spread of Covid-19 has made the issue of biosafety a priority, so proper and careful implementation of protocols plays an essential role.

According to recent research by the New York Times, dentists and their assistants are among those most at risk of Coronavirus. This can easily be attributed to the fact that exposure to potentially infectious bioaerosols is an everyday occurrence and that their work is carried out in close contact with patients.

The threat is not only posed by direct infection through respiratory droplets: a study in the New England Journal of Medicine suggests that the virus can survive up to 72 hours on plastic and steel, up to 24 hours on cardboard and just 4 hours on copper.

The time span varies depending on the characteristics of the surface type: less porous surfaces like plastic and steel are the worst because they do not absorb droplets as well, meaning that the virus remains active.

Dentists and all operators involved are required to work close to patients’ mouths: dentistry itself does not enable them to practise social distancing; moreover, the work they do tends to produce a high amount of bioareosol, one of the main carriers of the virus.

How will the work of dentists and their assistants change?

Proper procedures are still being defined by various institutions. However, some initial guidelines are emerging:

• Setting up your operating room: when setting up your room, standard procedures for cleaning and disinfecting surfaces must be followed, paying close attention to keep the room as tidy as possible and only preparing the instruments needed to carry out the scheduled treatment. Where possible, cover surfaces with protective or adhesive film.

• Dressing yourself:

○ gather your hair;

○ wash hands with hydroalcoholic disinfectant for at least 20 seconds;

○ put gloves on;

○ wear a surgical cap;

○ wear shoe covers;

○ wear a disposable gown;

○ wear eye protection;

○ put on an FFP2 mask and cover it with a surgical mask. By doing this, you can use your FFP2 mask for your next patient as well, after changing your surgical mask to avoid cross-contamination;

○ wash gloved hands with hydroalcoholic disinfectant for at least 20 seconds;

○ put on a second pair of gloves on top, which will cover the cuffs of your disposable gown.

• Carrying out operations/procedures: operations and procedures must be carried out in accordance with standard prevention protocols. Where possible, the number of operators and patient companions in the operating room should be kept to a minimum. To prevent the formation of aerosol, rubber dams and two surgical aspirators should be used where possible.

• Cleaning up the operating room: remove and discard any protective films on surfaces, as well as any disposable, single-use equipment used during the treatment. Then disinfect all surfaces and surgical aspirators. Air out the room for at least 15 minutes and take used instruments to the sterilization room.

• Undressing yourself:

○ remove your eyewear from the back, which is less contaminated, ensuring that you do not remove your cap when doing so;

○ remove your cap by gripping it from the middle and pulling it upwards;

○ remove your shoe covers;

○ remove your second pair of gloves;

○ remove your disposable gown;

○ wash the first pair of gloves with hydroalcoholic disinfectant for at least 20 seconds;

○ remove your first pair of gloves;

○ wash hands with hydroalcoholic disinfectant for at least 20 seconds.

The use of disposable, single-use products in healthcare is absolutely essential to ensure infection control during everyday appointments and procedures, and is even more important in light of the crisis we are currently facing.

Each of the steps listed in the guidelines above must be followed with the necessary personal protective equipment:

• Respiratory protection: disposable surgical masks (DM) and valve-less FFP2 respirator masks (PPE). If an FFP2 respirator mask with valve is used, a surgical mask must be worn over the valve;
• Personal Protective Equipment for eyes: glasses or face shields that also provide lateral protection;
• Other protective equipment: gloves, gowns, caps and disposable shoe covers.

Respiratory protection: surgical masks and respirator face masks

A proper distinction must be made between the use of disposable surgical masks and FFP2 respirator face masks: the former act as a barrier against the direct transmission of infectious agents and provide protection from fragments and corrosive/harmful material, while the latter are mainly used when treating infectious diseases.

When do we use surgical masks?

• when interacting socially in the waiting room and when completing administrative formalities with patients;
• when carrying out all sanitisation steps in the operating room before and after an operation/procedure (if the dental procedure involves the formation of aerosols, the staff member must continue using a respirator face mask during decontamination, washing and sterilization);
• in any situation where keeping a distance of at least one metre is not possible.

Disposable surgical masks must be changed and replaced after each patient. Current guidelines issued by major medical institutions recommend changing the mask every 20 minutes when used during procedures that produce high levels of bioaerosol, and every 60 minutes during standard procedures.

When do we use FFP2 respirator face masks?

• during procedures in which we are exposed to bioaerosols for more than 15 minutes and/or there are no other protective containment systems (e.g: rubber dams);
• when treating patients suspected, likely or confirmed to be infected.

FFP2 respirator face masks are disposable and can be used for several hours. The same respirator mask can be used with several patients if a surgical mask is worn on top. This surgical mask must be changed after each patient.

Personal Protective Equipment for Eyes: face shields

The Coronavirus outbreak has shown that eyes are a potential route for infection, which is why it is beneficial that all dental health operators ensure that proper protective eyewear is used. Depending on the situation, face shields and glasses—as mentioned briefly below—are more suitable.

When do we use face shields?

• whenever sprays/aerosols containing blood or saliva, or any other bodily matter from the patient, are expected to be produced during a surgical procedure.

When do we use protective glasses?

• whenever sprays/aerosols are expected to be produced during a surgical procedure. They can be used as an alternative to face shields or, better yet, worn with them. Glasses that protect the part at the side of your eyes are preferred;
• when cleaning operating rooms. or when washing and disinfecting work equipment;
• when carrying out administrative formalities, if keeping a distance of one metre is not possible;
• whenever you enter a room where an operation is being carried out.

When do we use glasses for UV525 rays (blue light) from polymerisation lamps?

• using them together with face shields is recommended for procedures where exposure to artificial optical radiation is expected.

Other disposable PPE

When should disposable gloves be used?

• always. It is recommended that two pairs of gloves are used for each type of procedure. The first pair should be removed after being used, and the second should be removed after all other items of PPE have been removed and this pair itself has been washed with disinfectant.

When do we use disposable gowns?

• using these is always recommended. These are obligatory for surgical procedures, with an important distinction:

○ no aerosols produced: SMS surgical gown;

○ aerosols produced: surgical gown with overlaying long-sleeved NWT layer;

• whenever you enter a room where an operation is being carried out.

When do we use a cap?

• using these is always recommended. These are obligatory during surgical procedures where sprays/aerosols are expected to be produced. In this instance, it is recommended that an autoclavable cotton bandanna is worn underneath the disposable cap;
• whenever you enter a room where an operation is being carried out.

When do we use shoe covers?

• using these is always recommended. These are obligatory during surgical procedures where sprays/aerosols are expected to be produced;
• whenever you enter a room where an operation is being carried out.

The ongoing Coronavirus crisis requires doctors, dentists and assistants to review every aspect of their working methods to ensure better personal and patient safety: from correct/suitable use of personal protective equipment to dental-practice procedures, and each individual step in the sterilization process.

Getting back to a position where we can guarantee ongoing care is our main aim, but this can only be achieved by carefully reviewing, methodically reorganising and properly managing procedures, resources and dedicated areas, in accordance with protocols that will be established to limit and prevent the possibility of infection.