This study provided an insight on the signs/symptoms referable to COVID-19, the protective measures and the PPE adopted in the dental setting during the operative procedures as well as the level of awareness and risk perception regarding the COVID-19 pandemic in Italian dental hygienists. The online survey was carried out during the period of maximum diffusion (April, 2020) of SARS-CoV-2 in Italy. Dental hygienists who completed the questionnaire carried out their professional activity in all Italian regions and the total number of responders was quite high, with differences among regions.
At the time of writing, there are no published papers in the literature on COVID-19 and dental hygienists; on the web, however, the outcome of a survey on dental personnel (no dentists) from 30 countries is retrievable . In addition, some papers that evaluate, through a questionnaire, different aspects in clinical practice administered to dentists are also available [11, 14, 15].
Due to close face-to-face contact with patients, dental personnel, including dentists, dental hygienists and dental assistants, are repeatedly exposed to respiratory tract secretions, saliva and blood and, consequently, they are exposed to SARS-Coronavirus-2 infection. The use of rotary and vibrating dental devices, producing a high amount of aerosol and splatter, possible vehicle of pathogens, increases the risk. Dental personnel, operator and assistant, were highly contaminated by the use of an ultrasonic scaler especially on the head, chest and inner surface of the face mask . The Occupational Information Network has determined which job category runs the highest risk of COVID-19 exposure, based on scores considering the contact with people, the physical proximity to others and the exposure to disease/infection. Dental hygienists took the first place, dental assistants the third and dentists the fourth place . Consequently, it is important that they take effective measures to protect themselves and patients against the virus. In the present survey, only a low percentage of the entire sample declared to be positive to the SARS-CoV-2 and this percentage is similar to that found in low COVID-19 prevalence areas. This data might suggest a low infection rate among dental hygienists, just as the appropriate preventive measures were correctly implemented by the majority of the dental hygienists; however, the prevalence of COVID-19 in the different Italian regions is very inhomogeneous with areas particularly affected by the virus and areas in which few cases have been found.
It is important to underline that the participants are aware of the method of diffusion and transmission of COVID-19. As part of the infection control measures, this information is essential in the dental office to adopt measures and wear PPE to control the infection transmission. Likewise, it is encouraging that a large number of dental hygienists are aware of the need for triage of patients and the recording of their body temperature. Understandably, both of these facts can provide a clearer idea of potentially infected patients and their precautionary management in the dental office. Neither preventive measures, nor the use of PPE seems to be conditioned by the years of work experience declared by each subject. In all the three categories of work experience considered (from less than 10 years to more than 20 years), dental hygienists have demonstrated that they know and adopt what national and international recommendations suggest to do in the current pandemic situation.
Despite the findings reported, it is important to stress that this survey had some limitations.
First, data were collected in a short period of time, bearing in mind the rapid effect that this outbreak had, both psychologically and clinically, on dental hygienists in relation also to the different geographical areas, as some were more affected by others. This might have had an effect on the precautionary measures adopted; however statistically significant differences were found only for few measures, adopted primarily by dental hygienists working in the COVID-19 medium/low areas than in the high prevalence area.
Secondly, not all Italian potential participants accepted to participate to the questionnaire, therefore the outcomes reported (i.e. precautionary measures or PEE adopted) are ascribable to a sub-group of the reference population, subgroup that is probably more interested and attentive in implementing the appropriate preventive measures.
Moreover, a limitation of the study might be attributable to gender imbalance, since the sample included a high prevalence of females. This reflects both the dental hygiene as a female dominated profession, but also the different compliance to this kind of investigation between genders . This female imbalance might explain why washing hands before and after each procedure was the most reported preventive measure, since gender disparities were previously reported regarding this fundamental preventive habit . However, this measure was also the most reported even among Italian dentists, although the sample was largely formed by males .
Unlike what could be expected, the majority of interviewed dental hygienists reported to be confident to avoid the infection during working activities. These findings disagree with those reported by Italian dentists, of whom only a small number of subjects working in Lombardy, a Region with a high prevalence of COVID-19, believe to be confident in avoiding SARS-CoV-2 . This disagreement can be explained not only by the different prevalence of infection in different geographical areas, which can make the risk appear more or less pressing, but also by the age of the participants, which is lower among dental hygienists than dentists. Older adults tend to see more risk in behaviors in health domain compared to young adults .
Considering that the epidemiological situation of the SARS-CoV-2 infection is still in evolution, it is feasible to verify in the near future whether the preventive measures implemented by dental hygienists will be maintained even when the level fear linked to the COVID-19 will be no longer so high.