Importance of education on infection control and on the hand skin health of dental personnel

Background. Hand hygiene plays a significant role in infection control, yet it is performed correctly only 40% of the time. The daily use of soap, disinfectants and gloves can also affect hand skin health. Periodical educational interventions regarding hand hygiene can improve infection control. Objectives. The current study aimed to identify the existing hand hygiene practices applied by dental personnel, to evaluate knowledge about infection control, to determine the adverse effects of hand hygiene on the skin, and to assess the effectiveness of the educational interventions concerning these topics. Material and methods. This study was carried out at the Vilnius University Hospital Žalgiris Clinic, Lithuania. At the 1 st stage, data was collected by using a self-administered questionnaire. At the 2 nd stage, dental personnel underwent an educational intervention and the surveys were redistributed to determine any changes in the level of knowledge.


Introduction
The human mouth contains one of the most diverse microbiomes in the human body.More than 1,000 species of bacteria are found in the oral cavity. 1 Regarding the recent COVID-19 pandemic, the issues of infection control and hand hygiene in the dentistry field have come to light.Dental personnel is exposed to an immense risk due to the specificity of dental procedures, which involve faceto-face contact with patients, frequent exposure to saliva, blood and other fluids, the handling of sharp instruments, and the generation of aerosols and droplets. 2Although appropriate hand hygiene is a routine procedure in dental practice, the compliance rates are relatively low. 2 Data shows that proper hand hygiene is achieved only in 40% of cases. 3Given the current situation, improvement in this area is of utmost importance.
The World Health Organization (WHO) has declared that hand hygiene is necessary before and after touching the patient, before handling invasive devices, after removing sterile or non-sterile gloves, and after contact with blood and other body fluids or inanimate surfaces and objects. 4Data shows that hand hygiene is most often performed after exposure to organic fluids (98.5%), before invasive procedures (87.5%), before clean/aseptic/surgical procedures (83.1%), and between patients (81.4%). 5However, proper hand hygiene after contact with patient surfaces is usually not achieved. 5Such behavior increases the risk of cross-contamination between the patient and medical personnel. 6,7and hygiene includes cleaning the hands with soap and water and/or alcohol-based hand rub (ABHR).Indications for hand washing are as follows: before the first patient; after using a toilet; when the hands are visibly dirty or soiled with blood or other body fluids; or if there is no ABHR. 4n all other clinical situations, dental personnel should use just ABHR.][10] Unfortunately, healthcare workers often ignore ABHR due to the erroneous belief that it provokes adverse skin effects, and use soap unnecessarily. 6This often leads to the deterioration of the hand skin condition, including impaired barrier function, a change in the skin flora, increased bacterial shedding and sensitivity of the skin, or other adverse reactions. 10Moreover, severe dermatological pathologies, such as contact and allergic dermatitis, can develop. 4,7,9he use of gloves is part of the standard precautions against cross-contamination in medical offices. 11Latex gloves may cause allergic reactions because of various chemical agents (antioxidants, accelerators, activators, etc.) used during the manufacturing process or due to their protein content.Latex allergy occurs in 1-2% of the total population, but the sensitization rates in healthcare providers are 2 times higher than in the general population. 12The main reasons for sensitization are 'wet work' and long working hours while using gloves. 13nd hygiene interventions are described as hand sanitization programs to increase hand hygiene compliance.These interventions vary from simple (e.g., increased availability of cleaning agents) to complex (e.g., multimodal programs involving education, environmental restructuring, reminders, and performance feedback). 14,15ingle-component interventions improve hand hygiene practices, but multimodal strategies are more effective over a long term. 16Education, feedback, support from a team leader, and the accessibility and visual reminders of hand hygiene are all elements that increase compliance. 16][16][17][18] However, the compliance rates decline with time; therefore, regular post-interventions should be considered. 16he present study aimed to identify the existing practices reported by dental personnel for hand hygiene, to evaluate their knowledge about infection control, to determine adverse effects on hand skin, and to assess the effectiveness of the educational interventions concerning these topics.

Material and methods
The study was conducted in 2 stages.At the 1 st stage, data was collected using a self-administered questionnaire.The questionnaire included multiple-choice questions about hand hygiene habits (daily cleaning with soap and ABHR), infection control knowledge (questions from the WHO's "Guidelines on hand hygiene in health care" 4 ), hand skin health, the use of gloves, and the manifestations of adverse reactions, such as dryness or redness.The study included dental specialists, general dentists, dental resident doctors, and dental assistants/nurses working the day shift in the Žalgiris Clinic, Vilnius University Hospital, Lithuania.The day shift in the Žalgiris Clinic lasts from 8 a.m. to 2 p.m. or from 2 p.m. to 8 p.m. (in general, 6 h).Only 120 dental workers from the Žalgiris Clinic met these criteria, and all of them were given a first-stage questionnaire.After analyzing the results from the 1 st stage, we assessed the most common mistakes.Accordingly, we prepared educational material and introduced it to the dental personnel at the 2 nd stage.The instructional video material was uploaded to the Žalgiris Clinic intranet and informational posters were hung in each consulting room above the washing sink at eye level.A week later, the same questionnaires were redistributed among those who participated in the 1 st phase of the study and saw the instructional video material to determine any changes that occurred after exposure to the educational intervention.

Statistical analysis
Statistical analysis was performed using the IBM SPSS Statistics for Windows software, v. 23 (IBM Corp., Armonk, USA).Data normality was checked.
The χ 2 test of independence was used to determine statistically significant associations between 2 variables, and the non-parametric McNemar's test was used to assess changes between first-and second-stage responses.A statistically significant difference was assumed at 5% (p ≤ 0.05).

Results
A total of 120 persons participated in the 1 st phase of the study.The response rate was 80% (96/120).The majority of respondents were women (92.7%), and the age of the participants ranged from 20 to 66 years (39.02 ±11.17 years).For further analysis, the groups were divided according to specialization (nurses/dental assistants, resident doctors, dental specialists, and general dentists).The majority of respondents in both phases were nurses/dental assistants.In the 2 nd phase, 96 individuals participated and the response rate was 87.5% (84/96).The majority of respondents were also women (89.3%), and the age ranged from 24 to 66 years (40.41 ±11.70 years) (Fig. 1).

Knowledge about infection control
Nearly 100% of the respondents identified the situations where hand hygiene was necessary.However, the proper hand hygiene method (the use of soap and water and/or ABHR) was selected by only 53.4%.Table 1 shows to what extent correct hand hygiene measures were complied with at the 1 st and 2 nd stage of the study.At the 1 st stage, 89.6% of respondents chose the proper hand hygiene method after exposure to organic fluids and 76.0% before invasive procedures.With regard to other measures, less than 34% replied correctly.After the educational intervention, a 21.4% improvement was observed in the selection of the proper hand hygiene method.However, at the 1 st stage, when the respondents were asked to selfevaluate (on a 100% scale) to what extent they performed appropriate hand hygiene, a high rate of compliance was indicated (82.7%).
Eighty-three percent of the respondents correctly answered the question about the recommended hand washing time when using soap (Fig. 2).In addition, 79.8% knew the time required for the use of ABHR (Fig. 3).
At the 1 st stage of the study, 47.9% of the respondents knew that during hand washing, the direction of water flow should be from the wrists to the fingers.After the educational intervention, a 25.9% improvement in this aspect of knowledge was observed (Table 1).
A difference in the opinions of the respondents regarding hand washing with soap and the use of ABHR at the 1 st and 2 nd stage was evident.After the intervention, the average improvement was 30.3% (Fig. 4).
Self-evaluation showed that 80.6% of the dental personnel believed they had enough knowledge about infection control and hand hygiene.A borderline statistically significant difference (p = 0.049) was observed between different professions, where 42.9% of general dentists indicated a lack of information as opposed to only 10.4% of nurses/ dental assistants.

Hand skin health
According to the self-reports, the prevalence of eczema and atopic dermatitis was 8.5% and 4.2%, respectively.Most often, the dental personnel indicated having a dry (45.8%) or mixed (32.3%)hand skin type.
A total of 50.5% of the respondents regularly used hand cream/lotion.However, only 38.5% used hand cream/lotion 3-4 times a day.Mostly emollients were used to counteract hand dryness (35.1%).The use of emollients after the edu-cational intervention increased up to 77.4%, and a 26.9% improvement was evident.All healthcare workers who had atopic dermatitis (p < 0.05) and 50% of those who had eczema did not use hand skin emollients regularly.Only 19.8% of the respondents indicated that they did not have adverse hand skin effects, with the remaining participants specifying various complaints.There were no statistically significant differences in the distribution of various skin side effects within particular profession groups (Fig. 5).

Use of gloves
A total of 62.4% of the respondents wore gloves for 7 h or more, 36.6% for 3-6 h, and 1.0% for up to 2 h.Half of the respondents indicated working with gloves for 10 years or more.
Most often, nitrile (47.7%) or latex (46.7%) gloves were used.Approximately 1/3 of the participants (27.4%) reported irritation reactions linked to the wearing of latex gloves, 6.4% to nitrile gloves and 6.3% to vinyl gloves.

Effectiveness of the educational intervention
The answers to the same questions were compared between the 1 st and the 2 nd stage.The responses to 4 out of the 10 questions were significantly improved after the educational intervention (Table 1).The average improvement after educational training was 25.4%.
Most respondents (95.2%) agreed that educational training had an impact on their knowledge.A total of 54.75% of the healthcare workers indicated that infection control and hand hygiene training should be carried out every year, 29.75% indicated every 6 months, and 15.5% every 3 years or more.

Discussion
One of the critical issues in hand hygiene is recognizing situations when particular hand preparation is required. 4edical personnel tend to forget about hand hygiene when contact with patient surfaces is expected as well as after it. 5This study found that the compliance rates declined after the removal of gloves, but the results were much better after the educational intervention.After such an intervention, appropriate hand hygiene was performed by 100% of the personnel in all other situations (after contact with organic fluids, before invasive procedures, before each patient, and after using a toilet).Although dental workers self-evaluated their knowledge as very good, the answers about the correct method to use in different situations revealed that their knowledge was inadequate.At the 1 st stage, only half of the staff knew which situations required washing hands with soap and/or ABHR.
Sodium lauryl sulfate (SLS) is a detergent commonly used in soap due to its cleansing properties.However, it affects the natural skin barrier and causes skin dryness, irritation and allergic reactions. 19Also, it is widely known that SLS irritates the skin more than ABHR. 9For this reason, the use of soap should be avoided in situations that do not require it.In this study, the majority of dental personnel washed their hands with soap before each patient and after removing gloves, while these situations require only the use of ABHR.In another study, 68% of respondents reported that they washed their hands with soap between patients and 65% after removing gloves; in contrast, only 3% used ABHR between patients and 6% after removing gloves. 20After the educational intervention, improvement in choosing the proper hand hygiene method was evident, and fewer workers believed that ABHR dried skin to a greater extent than soap.
Another essential aspect concerning hand hygiene is the adequate application time for soap and ABHR.Using ABHR for less than 15 s does not destroy certain pathogens, while using it for more than 15 s is not contraindicated, as despite its enhanced antiseptic properties, ABHR does not irritate the skin. 21On the contrary, in the case of soap, a long application time is not recommended, as soap contributes to hand skin dryness. 9One study found that the majority of health professionals washed their hands with soap for 15 s or longer, while others chose a shorter time. 22In the present study, the majority of dental personnel washed their hands with soap for the recommended time (15 s), but some selected a longer duration of 3 min.Most of the respondents followed the recommended time for hand disinfection with ABHR.
It is well known that during hygienic hand preparation, water should flow from the wrists to the fingers.Washing in this manner allows water to flow from the least contaminated area (the wrists) to the most contaminated parts (the fingers). 4In the first-stage questionnaire, only half of the respondents answered this question correctly.
It might be due to the fact that some respondents confused this question with surgical hand preparation.This aspect was mentioned in the educational video material and a significant improvement was achieved.
There is no doubt that the daily use of soap and disinfectants, working with gloves, and 'wet work' affect hand skin health.A European population survey showed that 54.1% of the population had a dry hand skin type. 23In the present study, nearly half of the respondents also had dry skin.This type of skin is even more vulnerable to irritants, and thus side effects can appear quickly. 23In a study by Harnoss et al., the most common adverse hand skin reactions among surgeons of various specialties were dryness, nail splitting and cracking, itching, and redness between the fingers, whereas 49% of doctors reported no complaints. 24In this study, the most common side effect was also dry hand skin, but it occurred almost 5 times more often, while the response 'no complaints' was noted 2.5 times less frequently than in the abovementioned study.Both studies had different population samples.In the first one, most of the respondents were men and all of them were surgeons, for whom there are specific hand hygiene requirements.In our study, there were more women, and all the respondents were dental personnel.
Due to specific working conditions, dental personnel are at high risk of developing a dermatological pathology. 9he incidence rate of eczema varies in the literature.The 1-year prevalence among dentists in Japan was 36.2%. 9In healthcare workers in Denmark 25 and Sweden, 8 the prevalence was 21%, and in Dutch healthcare workers it was 12%. 26The prevalence rate in the present study was less than 9%, but this may have been due to the small-scale study population, and also to the fact that no objective tests were carried out to confirm the diagnosis.The age of patients with eczema was lower than in the general study population, and the same tendency has been observed by other researchers. 9,26One possible explanation for this finding is that eczema tends to develop at the early stages of working, and health workers who are severely affected may leave their profession at a young age. 9The prevalence of another common disease -atopic dermatitis -also varies.In Japan, its incidence among dental practitioners was 15.8%, 9 and in healthcare workers in Denmark and Sweden, the incidence was 14.5% 8 and 22%, 27 respectively.The prevalence of atopic dermatitis in this study was also low (4.2%).
Latex allergy is an occupational hazard for medical personnel.According to various studies, latex allergy affects about 4% of healthcare professionals. 28,29In one study, 41.4% of nurses experienced irritation reactions caused by latex gloves. 30Nurses who reported an irritation reaction were given a skin prick test and 9.8% of them were diagnosed with latex allergy.In the present study, the prevalence of an irritation reaction related to wearing latex gloves was 27.4%.As a skin prick test was not performed, no verified data on latex allergy was available.
The regular use of skincare products could help to prevent dermal side effects in healthcare workers.The protective action of such products most likely comes from 2 different components of the cream (oil and wax), which prevent, to some extent, the evaporation of epidermal water, and polyalcohols, such as glycerol and propylene glycol, which have moisturizing properties. 31It is recommended to use hand lotion or cream after each hand washing. 31Alcohol-based hand rub should be used no sooner than 5 min after lotion application. 32However, for various reasons, the use of emollients among medical personnel varies.According to some studies, 25% of surgeons and 91% of nurses use hand cream/lotion. 24,33Regarding the use of handcare products, emollients are usually used when the skin is dry, before and after work, or randomly during the day, and rarely before and after each patient. 24The same tendencies were evident in this research; skincare products were used irregularly only by half of the staff.After the educational intervention, the use of emollients increased significantly.
An important aspect of this study was the educational intervention.The most common mistakes from the 1 st stage were identified and targeted for improvement in the intervention.This study demonstrated that it is unnecessary to repeat all information, and that only targeted data can be provided.According to Dale's Cone of Experience, humans remember only 10% of the information they read and 30% of what they see. 34That is why the current educational intervention used a poster (readable information) and instructional video (visual communication) material.A crucial and novel aspect is that after receiving the selected information, the respondents answered the questions about hand hygiene and use of the hand hygiene methods in different situations much more accurately, and a general improvement was observed.Therefore, this study demonstrates that repeating targeted information is sufficient to achieve better knowledge.Moreover, it can be predicted that the workers adapted this knowledge into practice, and that hand skin health also improved.
16][17][18]35 A recent systematic review concluded that multimodal training approaches raised hand hygiene compliance from a baseline of 51.5% to 80.1%. 18Another long-term study found that before training, hand hygiene was performed 63.6% of the time, and after 8 years of monitoring and multiple interventions, it improved to the level of 84.4%. 35The researchers also noted that due to this improvement, less hospital-related infections occurred. 35The results of this study confirm that educational interventions can improve knowledge about the hand hygiene practice and infection control principles.

Conclusions
The dental personnel performed hand hygiene correctly in 53.4% of cases.Generally, the hands were washed with soap too often, while ABHR was avoided.Only 19.8% of the respondents never experienced skin problems.Training has a positive impact on hand hygiene and improves the knowledge of dental personnel.

Fig. 1 .
Fig. 1.Distribution of respondents by occupation and gender at the 1 st and 2 nd stage of the study

Table 1 .
Correct answers to the same questions at the 1 st and 2 nd stage of the study Data presented as number (percentage) (n (%)).ABHR -alcohol-based hand rub.