Reports & Studies

Protection from aerosols – S1 guideline of the German Society for Dental, Oral and Maxillary Medicine

PD Dr. Kristina Bertl, PhD MSc MBA

Since the outbreak of the pandemic and the resulting global spread of SARS-CoV-2, aerosol-generating activities have been a hot topic of discussion in dentistry. How should we handle them? How can we best protect our patients and ourselves? What measures should we take in daily clinical practice?

The DGZMK has very recently produced an S1 guideline on the topic „Dealing with dental patients in the event of aerosol-borne pathogens’“ which will certainly make interesting reading for all dental professionals. This guideline discussed the following topics and provided the following recommendations:

Triage of suspected cases

  • Suspected cases must be filtered out. This should be done at the latest before treatment measures are started, but ideally it should occur before the patient enters the dental practice, by telephone or by means of a notice on the practice door.
  • Patients must specifically be asked about typical symptoms of an infection with SARS-CoV-2.
  • Patients must specifically be asked about any potential contact with COVID-19-positive patients in the past two weeks.
  • The body temperature of suspected cases may be taken as part of triage.

Protection of at-risk groups

  • To protect at-risk groups from becoming infected with SARS-CoV-2, the benefit of giving dental treatment should be weighed against the possibility of infection with SARS-CoV-2. In addition, the dental treatment of such groups should be integrated into the working day in such a way that they have as little contact as possible with other patients.

Suspected and confirmed COVID-19 cases

  • Suspected and confirmed COVID-19 cases should preferably be treated at special centres, clinics or practices. In exceptional cases where this is not possible, any treatment required should be carried out at the dental practice, with physical and organizational segregation of these patients from the practice’s normal consultation hours, and in accordance with the hygiene and safety measures specified for this situation.


  • Distancing of patients from staff must be adhered to by complying with the minimum distance of 1.5 m at reception. The installation of a sheet of plexiglass at reception to protect colleagues from droplets may also be recommended.
  • The distance between patients from different households must be at least 1.5 m to minimize the risk of infection transmission through droplets.

Wearing of mouth and nose coverings

  • Upon entering the dental practice, patients should be asked to wear a mouth and nose covering until their treatment starts and after it has finished.

Consistent implementation of basic hygiene

  • Consistent implementation of basic hygiene including hand hygiene. Upon entering the dental practice, patients should be asked to wash or disinfect their hands. According to the epidemiological situation, newspapers, toys and other unnecessary items in the waiting room can be dispensed with.
  • Because transmission via contact surfaces cannot be ruled out, a regular wipe-down disinfection of contact surfaces should be performed in addition to basic hygiene.

Continuous wearing of mouth and nose masks

  • Employees should continuously wear a mouth and nose mask, including outside the treatment room. They should also consistently adhere to the minimum distance rule, including during breaks and in changing rooms.

Testing of staff

  • Staff members who display symptoms of a COVID-19 infection must be isolated immediately, and a PCR test should be used to test for the presence of an infection.
  • There are insufficient robust data to support the testing of symptom-free staff in the dental practice.

Testing of patients

  • Until they can provide a negative test result, patients who display symptoms of a COVID-19 infection should only be treated in the event of an emergency.
  • In the case of dental emergencies, emergency treatment should be performed in compliance with the protective measures listed in chapter 8.
  • Untargeted testing of asymptomatic patients should not be carried out, although it may be useful in the event of an increased local risk.

Use of protective face visors

  • The additional use of protective face visors may further increase safety.

FFP2/FFP3 masks

  • Dental staff who come into contact with infected patients or with patients who are reasonably believed to have a SARS-CoV-2 infection should wear an FFP2 or FFP3 mask, or the equivalent N95 mask.

Mouth and nose mask

The following recommendations should be followed when giving dental treatment to patients who are not suspected of having a SARS-CoV-2 or tuberculosis infection:

  • During treatment, dental staff must wear a medical mouth and nose mask. By ensuring the mouth and nose mask fits correctly (good fit in the nasal area, and the sides of the mask should be as tight as possible) and by observing handling discipline, this will ensure the best possible barrier against pathogens.
  • There are currently no robust data to support the wearing of an FFP2, FFP3 or N95 mask as standard during all dental activities that involve the use of water-cooled instruments.

Resource-conserving use of masks

  • In the event of supply shortages related to COVID-19, an individual may reuse or reprocess their own mouth and nose masks and FFP masks.
  • A practical approach to reusing masks may consist of giving each employee at least five masks to use on daily rotation. This is because any possible SARS-CoV- 2 contamination of the four unused masks will be inactivated after five days at the latest.
  • Personal reprocessing of masks is an alternative option. In terms of the reprocessing procedure, masks should be reprocessed in a sterilizer (e.g. at 121°C), because this method has been proved to be effective and gentle on materials.

Mouth-rinse solutions

Just before their procedure, patients should be asked to rinse their mouth for 30–60 seconds.
Options are:

  • ≤ 0.1% Octenidin®
  • 1–1.5% H2O2
  • 0.2% povidone iodine
  • 0.2% chlorhexidine
  • 0.2% cetylpyridinium chloride
  • ≤ 0.25% sodium hypochlorite
  • Dequonal®
  • Listerine cool mint®

Protective measures

  • If possible, a dental dam should be fitted over the mouth.
  • Consistent and high-volume suction must be ensured. In addition, it should be ensured that a diameter-optimized suction tip (≥ 10 mm) is used. Provided that this is ensured, there is currently no reliable evidence to support the use of additional suction devices.
  • High-volume spray mist suction must also be used in treatment methods that are performed without a dental assistant, for example professional tooth cleaning.
  • After treatments in which aerosols have formed, the treatment room should be ventilated effectively.
  • Nearly all instruments used in the dental practice that rotate rapidly or vibrate at a high frequency/maximum frequency require the use of a cooling medium. Powder–water polishing devices also require a combination of air, liquid and powder to generate the cleaning jet, which is why all these instruments are inherently associated with a pronounced spray mist formation.
  • Consequently, the operation of these devices should be avoided among patients who are reasonably believed to have COVID-19, provided this is clinically possible.

The wording of the recommendations has been taken directly from the guideline.