Effects of wearing personal protective equipment (PPE) and its role in affecting the work efficiency of dentists during the COVID-19 pandemic

1 Introduction

The COVID-19 pandemic has caused unprecedented changes in all aspects of our life, especially for healthcare workers. Dental professionals fall under the high-risk category [1] and are most likely to be exposed to COVID-19 virus = SARS-Cov-2 as they work near the oral cavity. The personal protective equipment (PPE) used by healthcare workers includes close-fitting N95 face masks/powered air-purifying respirators (PAPR), protective eyewear, gowns, and surgical gloves. In real-world practice, wearing PPE is uncomfortable for healthcare workers, especially if worn for an extended period, and dentists are no exception. Studies have shown that wearing PPE, face shields, and N95 masks increases dentists’ discomfort [2, 3]. Adverse skin reactions [4] and an increase in the frequency of headaches [5] are seen due to the prolonged use of mouth masks and face shields. Hence, it is critical to identify the problems associated with wearing PPE at an initial stage to mitigate or prevent them from progressing and reducing the quality of patient care.

Numerous studies describe the knowledge, attitudes, and practices regarding PPE and their usage patterns among dentists from different parts of the world, especially in the context of the COVID-19 pandemic [6]. Comparisons have been made with age, experience, specialty, gender, type of practice for PPE usage, and effects. However, the information available in most of the previous research is primarily empirical [7, 8].

Studies that delve into the detail and specifics of PPE usage and the symptoms of injuries and discomfort associated with their use are relatively uncommon. There is a paucity of reports that have described the possible risk factors associated with decreased work efficiency with the use of PPE. Many pre-existing risk factors can magnify the discomfort and possible loss of efficiency caused by PPE. Thorough knowledge of these risk factors may help dentists take preventive action to mitigate the adverse effects of wearing PPE for long hours. Hence, the study’s objectives were to obtain information from a cross-section of dentists regarding their PPE usage and to evaluate the possible risk factors which influence the working efficiency of dentists.

2 Materials and methods

A 31-item cross-sectional survey with a structured multiple-choice questionnaire was designed. A cross-sectional study design was used as it helps capture a specific point in time, which describes multiple variables and allow the researchers to compare them simultaneously. Two subject experts validated the questionnaire and made minor corrections. It was divided into the following sections: demographic data; duration and type of PPE used; signs and symptoms like skin abrasions; headaches arising from the use of different components of the PPE; and other infection control procedures. The dentists were also asked about the effect of adopting these protocols on the overall work efficacy. Pictorial depictions and photographs were used to describe the questions. Social media and email were used to circulate the questionnaire among dental professionals working in diverse setups - private, hospital/polyclinic, and hospitals attached to dental schools worldwide. All the completed forms were sought for three months, after which the survey was closed. After eliminating the incomplete questionnaires, the final sample of 317 was obtained. Responses obtained during the study were kept strictly anonymous and confidential. Ethical approval from the Institutional Ethics Committee (394/2020) was obtained. Participation in the survey was voluntary. The inclusion criteria were: dentists who wore PPE while working in clinical settings, aged 23 years and above and provided informed consent.

SPSS version 20 statistical software (IBM Corp) was used for data analysis. Frequency distribution was done to describe items included in the survey. Percentages were used to describe the frequency distributions. Spearman’s Rank correlation was used to test the correlation between efficiency-related variables. Binary logistic regression analysis was conducted to test the associations for reduced work efficiency. Binary logistic regression was used to analyze multiple independent variables or predictors influencing a binary outcome [9].

3 Results

A total of 317 respondents from 10 countries (India-285, USA-12, Malaysia-9, Australia-1, Kenya-1, Middle East- 8 and Nepal-1) returned the completed forms. Amongst the participants, 189 (57%) were practicing in a hospital attached to a dental school, while the rest were engaged in private practice/polyclinic. Two hundred and four (64%) participants reported using the full sets of PPE for three or more months. More than half of the dentists (54%) used full PPE. Most respondents (68%) did not have a pre-existing systemic illness. Among those with a positive medical history, migraine was most common, followed by headache, sinusitis, atopic dermatitis, and bronchial asthma. Most of the participants (84%) gave no history of allergy, while 7% of dentists reported allergy to latex and 6% to other chemicals. A total of 184 (55%) participants reported getting soaking wet while wearing PPE at the end of the long working hours. Many respondents (n = 286, 90%) reported that the use of PPE had led to reduced visibility of the operating field (Table 1).

N95 masks were used by a majority (78%) of our respondents, followed by a triple-layer surgical mask (26%). About half of the participants (47%) used mouth masks for more than six hours daily. Almost all participants (87%) used face shields. Most participants (77%) reported discomfort while wearing the N95 mouth mask. This discomfort was attributed to the tightness of the elastic band in 48% of the respondents, followed by feeling suffocated or hypoxic (41%) and sweating due to prolonged usage of the mouth mask (38%). More than half of the dentists did not report any change in the frequency of pre-existing headaches. Only 89 (27%) dentists had a rise in the frequency of headaches after using PPE. Headaches were associated with tightness of the elastic band of the mouth mask in 51 (16%) cases, due to the face shield in 36 (11%), and tightness of the head cap in 11 (4%) of the cases. Among the participants, 35 (11%) reported a new onset of headache, and 2 (0.6%) reported new-onset migraine. Only 51 (16%) practitioners reported an increase in the frequency of headaches (Table 2).

Table 3 describes the other symptoms and the sites of adverse skin reactions. We noted that 83% of participants did not report adverse skin reactions despite following the COVID-19 infection control protocols. Amongst the dentists with skin reaction, almost half of them, i.e., 74 (47%), reported dryness of skin to be the most common symptom, followed by itching (n = 49, 31%) and roughness (n = 32, 20%). Most of these skin changes were present in the hands (n = 36, 23%), nose (n = 27, 17%), and forehead (n = 18, 12%) regions. We found that 60% of dentists did not report pressure injuries. Amongst those who had injuries, 73 (23%) had stage 1 pressure injuries, and only one individual had stage 2 pressure injuries. Most pressure injuries were restricted to the middle third of the face seen in 47 (30%) participants, followed by the periorbital region and upper third of the face in 30 (19%) participants. About 267 (84%) respondents felt that their overall work efficiency had reduced after using PPE.

Age had a positive correlation with the frequency of PPE usage and handwashing. The pre-existing systemic illness was correlated with allergies, skin reactions, and pressure injuries. The duration of wearing a mouth mask was correlated with a reduction in the visibility of the working field (Table 4).

Binary logistic regression analyzed the role of factors like- prior history of allergies, medical conditions, being engaged in private practice, suffering from pressure injuries or adverse skin reactions, getting soaking wet after wearing a PPE, and country of practice in influencing work efficiency. Among all the factors, only two, namely having a prior medical history of systemic illnesses and getting soaking wet from wearing a PPE, were associated with reduced work efficiency during the COVID-19 pandemic (Table 5).

Exposure to bioaerosols during dental procedures is inevitable. Hence strict adherence to COVID-19-specific infection control protocols has become a part of routine dental practice. We found widespread usage of PPE among dentists, which was quite reassuring. At the same time, numerous issues caused by the usage of PPE were noted. The various problems related to perspiration and moisture like fogging visors/eyewear and excessive sweating were rampant among the respondents, which was in agreement with previous research [7, 11]. Increased duration of wearing mouth mask was associated with visibility reduction of the working field which is attributed to the fogging of eyewear which resulted in reduced work efficiency.

Skin dryness was the most common symptom amongst our participants and was seen on the hands. The health care professionals who adhere to hand hygiene protocols presented with skin dryness, itching, and irritant contact dermatitis (ICD), and this finding was similar to other studies [10, 13]. Prolonged usage of gloves increases the immunologic reaction to irritants [14]. A minority of participants had skin irritation due to PPE. It was clinically mild in intensity and mostly confined to the central region of the face. Hu et al. also reported similar results [4, 13]. The chances of COVID-19 transmission increase through skin abrasions that occur as a result of frequently touching the face [15].

Overall, around 20 % of the respondents reported pressure injuries due to wearing masks and visors. This was in line with previous research [12]. Mask indentations over the nose and cheek were the most common pressure injury reported by dentists in our study. Similar findings were put forth by Singh et al. [16] and Jiang et al. [17]. PPE-induced skin changes occur due to the friction and occlusion effect of the PPE [18]. Sweating, mask fit and wearing PPE duration contribute to these skin changes.

N95 respirators and medical masks used by health professionals for non-aerosol-generating procedures offer comparable protection against viral respiratory infections [19]. However, N95 respirators are uncomfortable, often causing skin irritation [20]. Around half of the respondents reported wearing masks for more than 6 hours a day, similar to the findings of Nguyen et al. [13]. Around one-third of the respondents reported headaches due to wearing PPE, with most of them citing the use of N95 masks. This was in agreement with previous research [21]. Some respondents reported de novo headaches, the frequency, and severity of which aggravated in respondents with a known history of headaches. Similar findings were stated by Lim et al. [5] and Ong et al. [22]. Proper fit is achieved by using elastics with adequate tension to hold the mouth mask in place. The tightness of these ties, when used for an extended duration, causes compression of superficial nerves and the sensitive skin of the face [5]. PPE-induced headaches may be caused by hypercapnia because of the snug seal around the nose and mouth [23, 24].

Since this study was conducted among a convenience sample of dentists, mainly from India and a few from other countries, the results cannot be generalized to all dentists. This was an online survey; hence, there is a chance of non-response, subjective bias, and the inability to reach remote areas with limited internet coverage. Lack of random sampling may lead to questionable (if any) statistical confidence and margin of error.

The fear of contracting COVID-19 is high among dental professionals [25, 26]. Hence, there may be a tendency to overdo the protection measures. This phenomenon has been observed among healthcare workers by other investigators [27]. For instance, dentists may wear both N95 and triple-layer masks for non-aerosol procedures, while the recommendations clearly state that the triple-layer alone is sufficient [28]. Such indiscriminate use may lead to added discomfort for the dentist. Our findings are in concurrence with previous researchers who found that dental professionals reported moderate to severely impaired working ability [7, 29]. We concur with the findings of Galanis et al. who stated that pre-existing risk factors like diabetes, obesity, and headaches were associated with decreased work efficiency [6]. In addition to PPE, the stress and anxiety of working in a high-risk COVID-19 environment may cause these symptoms. Some of the problems faced by dentists in our study are probably specific to tropical countries where air-conditioning is not the norm. The fear of droplet/aerosol infection forced many dentists/dental managers to desist from using air conditioners which further compounded the heat/perspiration problem. Getting soaking wet due to excessive sweating inside a PPE was one of the main reasons cited for reduced efficiency in our study. The acute shortage of PPE at the start of the pandemic would have forced many dentists to use one PPE for multiple patients, which could have led to problems associated with the prolonged wearing of PPE. This phenomenon was universal to most countries during the initial months of the pandemic. The excess of cheap, low-quality PPE after that, too, would not have helped matters.

This study is not without limitations. COVID-19 positive status of participants was not elicited, thus the possibility of headache as a consequence of post- COVID-19 syndrome was not documented. Regarding the duration of usage of the mouth mask, the questionnaire did not specify if the respondent used the mouth mask post the working hours also, i.e. during visits to the supermarket.

5 Conclusion

Some of the pandemic’s changes in infection control protocols may not go away with the pandemic. There is a need to introduce permanent protocols that mandate the doffing of PPE for every patient with a short break in a separate well, ventilated safe area where the skin can breathe and recover from the heat and pressure points caused by PPE. Non-irritant hand wash/sanitizers can also be made mandatory. Dentists need to take greater care in choosing the appropriate PPE so that there is no exacerbation of pre-existing illness, which may reduce their work efficiency.