|Year : 2020 | Volume
| Issue : 4 | Page : 355-359
Bacterial contamination of dental unit waterlines: knowledge and attitude among dental practitioners
Sakshi Shukla, Simarpreet Singh, Manu Batra, Deeksha Gijwani, Thounaojam Leimaton, Parul Mangal
Department of Public Health Dentistry, Surendera Dental College and Research Institute, Rajasthan, India
|Date of Submission||25-Oct-2019|
|Date of Decision||19-Dec-2019|
|Date of Acceptance||20-Jul-2020|
|Date of Web Publication||25-Sep-2020|
Dr. Sakshi Shukla
Post Graduate Student, Department of Public Health Dentistry, Surendera Dental College and Research Institute, Sriganganagar, Rajasthan
Source of Support: None, Conflict of Interest: None
Knowledge and attitude of dentists about dental unit waterlines (DUWLs) is of considerable importance as they along with patients are regularly exposed to water and aerosols generated from the dental unit.
The aim was to assess the knowledge and attitude toward contamination of DUWLs among interns and postgraduate students at a dental teaching institute in Sri Ganganagar, Rajasthan.
Settings and design
A cross-sectional questionnaire-based survey was conducted during December 2018 at a dental teaching institute in Sri Ganganagar, Rajasthan.
Participants and methods
A pretested structured questionnaire was used to collect desired information from postgraduates and interns. Data were subjected to descriptive and inferential statistics using SPSS (v21.0 IBM) software. Ethical clearance was obtained from Institutional Ethical Board before the start of the study.
Results showed that postgraduates had higher statistically significant mean±SD knowledge score (8.53±2.04) compared with interns (7.56±2.29) (P=0.02). The mean±SD knowledge score of male (7.70±2.19) and female (8.27±2.23) was found to be statistically nonsignificant (P=0.16), and the difference in mean±SD attitude score based on their clinical experience (amid their period of internship and postgraduation) was found to be statistically significant (P=0.03).
The participants who responded to this survey generally did not have enough knowledge about disinfection or testing of DUWLs. However, they were concerned about the well-being of the patient and were ready to adopt an effective method of DUWL disinfection in the future. Conducting workshop or continuing dental education programs on disinfection of DUWL may improve the attitude toward disinfection of DUWLs.
Keywords: contamination, dental practitioners, dental unit waterlines, knowledge and attitude
|How to cite this article:|
Shukla S, Singh S, Batra M, Gijwani D, Leimaton T, Mangal P. Bacterial contamination of dental unit waterlines: knowledge and attitude among dental practitioners. J Curr Med Res Pract 2020;5:355-9
|How to cite this URL:|
Shukla S, Singh S, Batra M, Gijwani D, Leimaton T, Mangal P. Bacterial contamination of dental unit waterlines: knowledge and attitude among dental practitioners. J Curr Med Res Pract [serial online] 2020 [cited 2020 Dec 1];5:355-9. Available from: http://www.jcmrp.eg.net/text.asp?2020/5/4/355/296148
| Introduction|| |
Mainstay of any infection control protocol is identifying all possible transmission routes of infectious agents. The devices that are placed within the oral cavity and that are not easily or routinely disinfected owing to their design or some other consideration are of particular concern in dentistry. A dental chair unit is equipped with a dental unit waterline (DUWL), which is a system of thin, plastic tubes that are used to irrigate the oral cavity during dental treatment and provide cooling to certain items of equipment such as air rotors and scalers.
Bacterial biofilms, which may be reservoirs for pathogens, may be present in dental unit water systems (DUWS). Biofilm is defined as a mass of microorganism attached to a surface exposed to moisture and forms just anywhere there is a moist nonsterile environment. It includes the surfaces related to natural water environment and also biomedical materials implanted in or associated with the human body. Dental plaque is the finest example of biofilm in dentistry. Thus, permanent infection of the water delivery system is caused by a type of plaque developing inside DUWLs.
The quantity of microorganisms present in the water used in the unit chair affects the safety of the patients and employees in dentistry. The infected water from the DUWL is recognized as a risk factor for systemic diseases as well as oral diseases as it may work directly or indirectly in the mouth, and it can cause serious infections, especially in the elderly and immune compromised patients, leading to conjunctivitis as well as respiratory-related diseases and bowel disorders.
As DUWL acts as a reservoir that facilitates the contamination of dental unit water resulting in the infection, the current study is an approach to assess the knowledge and attitude regarding bacterial contamination of DUWLs among interns and postgraduate students of a dental teaching institute in Sri Ganganagar, Rajasthan.
| Participants and Methods|| |
A cross-sectional questionnaire-based survey was conducted at a dental teaching institute in Sri Ganganagar, Rajasthan, during the time period of December 2018. The convenience sample included postgraduates and interns of the institute for assessing their knowledge and attitude toward contamination in the DUWLs. A total number of 154 questionnaires were distributed among the students who were present on the day of the survey. Of the students, 139 responded, leading to a response rate of 90%. As 18 forms that were incompletely filled were excluded, the final sample consisted of 121 participants.
Ethical clearance from the Institutional Ethical Committee was obtained before commencement of the study. The purpose was explained to the respondents before the start of the study. The identity of the study participants was kept anonymous. The structured questionnaire, containing 30 self-administered, close-ended questions used in the study, was formulated based on previous studies in the same field, which included 22 knowledge-based and 8 attitude-based questions regarding the microbial risk associated with DUWS.
The questionnaire was divided into two sections: section A contained sociodemographic details and professional background information of the participants, and section B comprised 30 close-ended multiple-choice questions based on the knowledge and attitude on DUWL. Total knowledge/attitude score was calculated on the basis of each participant's response. Each positive response was scored as '1' and another response as '0.' The total score was a simple sum of responses ranging from 1 to 30.
Data were subjected to descriptive and inferential statistics using SPSS (v21.0 IBM, Chicago, Ill., USA) software. Unpaired t test was used to compare the means, whereas χ2 test was used for comparing proportions. Pearson correlation was done to correlate the knowledge and attitude among all the participants.
| Results|| |
[Table 1] shows a comparison of mean scores of knowledge and attitude scores based on educational qualification. The mean knowledge score of undergraduates (7.56 ± 2.29) was found to be significantly lower than postgraduates (8.53 ± 2.04) (P = 0.02). The difference in mean attitude score of undergraduates (3.63 ± 1.77) and postgraduates (4.89 ± 1.62) was also found to be statistically significant (P ≤ 0.01).
|Table 1: Mean scores of knowledge and attitude according to educational qualification|
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[Table 2] shows a comparison of mean scores of knowledge and attitude based on clinical experience amid their period of internship and postgraduation. The variation in mean knowledge score of participants when compared on the basis of clinical experience was not found to be statistically significant (P = 0.38), whereas the mean attitude score of participants with such experience (4.05 ± 1.87) and those without the experience (4.96 ± 1.33) was found to be statistically significant (P = 0.03).
|Table 2: Mean scores of knowledge and attitude according to clinical experience (amid their period of internship and postgraduation)|
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[Table 3] shows that neither the knowledge nor the attitude score showed statistically significant difference by sex (P = 0.16 and 0.37, respectively).
[Graph 1] shows the scatter plot for the correlation between knowledge and attitude regarding disinfection of DUWL among dental practitioners. There was a positive correlation found between the knowledge and attitude (0.37), with statistically significant difference (P = 0.0003).
[Table 4] shows the response by the participants to the selected questions asked based on their sex, education, and experience (amid their period of internship and postgraduation). Results showed that the postgraduates had higher statistically significant proportions of correct responses when compared with the interns for the questions related to microbial growth in DUWL (P = 0.001), flushing of dental waterlines (P = 0.004), and guidelines of OSAP, American Dental Association, and Center for Disease Control and Prevention for sterilization (P = 0.004).
|Table 4: Response by the participants to the selected questions asked and based on their sex, education, and experience (amid their period of internship and postgraduation)|
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| Discussion|| |
Water supply to the apparatus connected to the unit chair, the mouthwash system, and the cuspidor is provided by the waterline of the dental unit. The backwash point as well as the waterline through which the water passes can be contaminated, and an environment where bacteria can easily reproduce is created if the patient's saliva or blood flows backward during the unit chair's operation.
Results showed that postgraduates had statistically higher significant knowledge score compared with interns, which is in accordance with the previous study conducted by Kengadaran et al. showing that postgraduate had higher mean knowledge score compared with undergraduate, and academicians had higher mean knowledge score than nonacademicians. The reason can be owing to postgraduates being under the direct surveillance of the staff or owing to more emphasis given on sterilization and disinfection in their postgraduate curriculum. However, the difference in attitude score was not found to be statistically significant.
Now with the fact that effectiveness of the DUWL cleaning regimen can be checked by testing the exiting water, when asked about the same, females and participants with clinical experience amid their period of internship and postgraduation were seen to have higher knowledge as compared with the others, though the results were not found to be statistically significant.
When asked about bacterial growth in the DUWLs, 61.4% of postgraduates responded correctly about the legionella growth, which was found to be statistically significant. According to Lal et al., this growth can be owing to the use of hard water, which can lead to the calcium coating of the inner surfaces of DUWS tubings and valves, which favors biofilm growth.
Over the question raised on infection caused by DUWL, 45.5% of the respondent in the present study were aware about the infections caused, whereas a study done by Robert et al. reported that only one-third of the dentist respondents in their survey answered that the water circulating in the dental unit chair waterline transports many microorganisms and that the dental patients and employees are thus at risk for infection.
About the disinfection of the waterline, 54.9% of the respondents in the present study answered correctly, which is more than the study conducted by Bhadra et al. in the year 2018, which showed that 40% knew the evidence-based methods and products regarding DUWL disinfection.
When asked about flushing of dental waterlines, 42.9% of the total participants were in its favor and 56.1% of the postgraduates responded correctly about its effect in controlling the contamination in DUWL, which was found to be statistically significant. According to the study conducted by Pankhurst et al., blood-borne viruses such as hepatitis B and HIV that are secreted in the saliva have been shown experimentally to be sucked back into the handpiece and have been recovered distally in the dental waterlines, and flushing can substantially reduce the level of bacteria present in water used for dental treatment from three various sources such as air water syringe, high-speed air turbine handpiece, and oral rinse.
In the context of national/international guidelines for controlling microbial contamination of DUWS, 51.2% of the total respondents were not aware about it, whereas 64.9% of postgraduates responded accurately regarding the guidelines and was found to be statistically significant. Contrary to this, in the results achieved by Kamma et al., 98% respondents were unaware of these guidelines, which indicates that the national dental organizations should be more proactive in the dissemination of information on this area of cross-infection control.
The safety of the patients and employees in dentistry is closely related to the number of microorganisms in the water used in the unit chair. Bacterially infected water from the unit chair is recognized as a risk factor for systemic diseases as well as oral diseases as it may work directly or indirectly in the mouth. Therefore, Center for Disease Control and Prevention and American Dental Association recommend a 500/ml maximum live bacterial level in the DUWL and a 200/ml colony-forming unit (CFU), respectively. Water is considered potable if it has less than 1 fecal coliform/100 ml and less than 500 CFU/ml. It has been argued that total bacterial counts higher than 500 CFU/ml might conceal the presence of some pathogens, as the detection of coliform bacteria is impaired by high bacterial loads. Thus, attention has to be paid to this hazardous issue in India.
The current study concluded that overall participants showed limited knowledge about disinfection or testing of DUWLs. However, they were concerned with the well-being of the patient and were ready to adopt an effective method of DUWL disinfection in the future. In this area, we need to sensitize the interns and update the postgraduates on this issue, so that they can apply the same in their clinical practice.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]