As mentioned earlier, healthcare workers in dental hospitals often face a high risk of occupational exposure. One of the manifestations of this high risk is the phenomenon of ROEs among healthcare workers. Reviewing previous studies, a substantial body of literature has reported the serious issue of ROEs among DHWs[22, 23]. Analyzing the hospital infection exposure data from 2016 to 2022, we found a significant number of individuals experiencing ROEs within the hospital. This piqued our interest in analyzing these ROEs events from the records, as we believe it holds significant importance. Firstly, ROEs may reflect underlying issues that need addressing in hospital infection control. Factors leading to repeated exposure may signify loopholes in protocols or areas where operational procedures need improvement. Understanding which occupational exposures are harder for healthcare workers to avoid can guide hospitals in targeted occupational exposure prevention training. Secondly, studying ROEs helps in a more precise analysis of risk factors. Due to challenges in attaining the number of service instances, relying solely on questionnaire data often yields a composition ratio of occupational exposure influencing factors. While this ratio somewhat reflects factors contributing to occupational exposure, it's not the best indicator of risk factors. Analyzing repeated exposure data allows for calculating the repeated exposure rates among different personnel types, providing a more accurate reflection of exposure risks across various professions. Lastly, studying ROEs in records helps reduce errors caused by underreporting. Many past studies have shown that even with strict reporting requirements for occupational exposure in healthcare institutions, a significant number of cases still go unreported[24]. This limitation affects exposure rates and the calculation and analysis of risk factors based on hospital records. However, studying repeated exposure events in hospital records allows for analyzing the rates and risk factors of repeated exposure within a relatively willing-to-report group at least, potentially reducing errors caused by underreporting and providing a more accurate understanding of risk factor severity.
In our study, we compared the relationship between the ROEs and initial occupational exposure in terms of personnel type, gender, operational scenarios, exposure sources, and department categories.
Clinical staff in a university-affiliated dental teaching hospital can be categorized into four roles: hospital dentists, dental students, hospital dental nurses, and dental nurse students. Previous research has suggested that the type of personnel can influence the occurrence of occupational exposure due to differences in skill levels. Typically, students are considered to face a relatively high risk of occupational exposure, possibly even higher than their supervisors, due to their lack of experience[20, 23, 25, 26]. Consequently, the focus of occupational exposure education has traditionally leaned towards students. However, in our study, we analyzed the proportion of ROEs among different personnel types from the perspective of repeated exposure. Surprisingly, hospital dentists had the highest proportion of ROEs over these seven years, and this finding was statistically significant. In contrast, the risk of the ROEs was lower for dental students and dental nurse students. It is undeniable that hospital dentists often engage in more complex and intricate tasks, which may increase the risk of occupational exposure. Previous research has also found that more experienced doctors may be less inclined to adhere to occupational exposure prevention strategies[22, 27]. And our data also reflect that the awareness of occupational exposure prevention among hospital dentists in our hospital may be insufficient. Hospital dentists may be the focal group for occupational exposure education in the foreseeable future.
Gender is one of the factors influencing occupational exposure. However, previous studies have shown varying impacts of gender on occupational exposure due to differences in study populations. A study conducted in Australia focusing on dentists and dental students indicated that females were more likely to experience occupational exposure in the form of needlestick injuries[20]. Some studies suggest that males are more prone to occupational exposure, with male healthcare workers even facing significantly higher risks compared to females[28, 29]. In our study, we examined the risk of ROEs among male and female healthcare workers in dental hospitals and found no significant differences, not even slight ones. This finding aligns with many other studies that have not observed significant gender differences in occupational exposure[22, 30]. While gender may influence an individual's fear of occupational exposure events and adherence to operational standards[31], we believe that these influences can be mitigated through training and other factors, which may explain the lack of significant gender impact on ROEs in our study.
Due to the varying nature of work undertaken in different areas of a hospital, occupational exposure risks differ across these settings. Previous research has commonly indicated that operating rooms, where frequent contact with patient fluids and sharp instruments is required, are associated with higher risks of occupational exposure. Studies from King Khaled Eye Specialist Hospital have shown that, for ophthalmologists, the operating room accounts for 60.7% of needlestick-related occupational exposure events[6]. Research from Ethiopia also highlights the operating room as the most common site for bloodborne occupational exposure[4]. Additionally, the nature of emergency work may be related to the occurrence of occupational exposure; the high intensity of emergency work and inadequate rest can elevate exposure risks[32, 33]. In our study, we categorized workplaces within a dental hospital as outpatient clinics, surgical operating rooms and wards, emergency departments, and clinical support units. The results indicated no significant differences in causing ROEs among outpatient clinics, surgical operating rooms and wards, emergency departments, and clinical support units in our hospital. Many dental procedures are performed in outpatient clinics, where healthcare workers frequently come into contact with high-speed rotating burs, various sharp instruments, patient fluids, and aerosols. From this perspective, outpatient departments in dental hospitals are also common sites for occupational exposure. Previous research has not extensively explored the occupational exposure risks between departments in dental hospitals. We believe that various workplaces in dental hospitals may carry higher risks of occupational exposure, particularly outpatient clinics whose risks should not be underestimated and may be similarly high as those in ward and operating rooms. However, we acknowledge that the sample size of exposure events in emergency rooms and non-clinical departments in this study is limited, and the analysis results may deviate from real-world scenarios.
Many studies have paid great attention to the pathways of occupational exposure[4, 14, 20, 33]. Various dental procedures performed by dentists often involve the use of high-speed dental handpieces and sharp instruments, which are essential tools for treating most oral diseases[34]. Occupational exposures frequently involve sharp instruments[34], and in this study, sharp instruments were identified as the primary cause of occupational exposure. Both initial and ROEs commonly involve injection needles, dental burs, suturing needles, files, probes, and knives. Dental prosthesis, orthodontic appliances, and sharp teeth of patients can also cause occupational exposures and repeated exposures, although data on these are relatively limited in this study. Additionally, aerosols and spatter generated during procedures such as high-speed dental handpiece use and irrigation are important pathways for occupational exposure. In our study, we compared the proportions of these pathways between initial and ROEs and found mostly no significant differences. However, in the analysis using binary logistic regression, the risk of ROEs due to suturing needles was over five times higher compared to scalpels and was statistically significant. Nevertheless, due to the small sample size, further research is needed to verify whether this result reflects clinical practice. Therefore, these factors can be considered equally important in causing ROEs among DHWs, and no pathway should be disregarded by healthcare workers themselves or hospital infection control departments. Furthermore, our statistical analysis of the reasons for multiple occupational exposures in the same individual showed that the proportion of repeated exposures through the same pathway was as high as 24.7%(Fig. 2). It is important to note that many exposure pathways can be prevented through simple preventive measures. For instance, wearing face shields and goggles can protect against exposure caused by splashing and spattering. Despite this, statistics still show that some healthcare workers experience ROEs due to splashes, indicating a lack of seriousness among a minority of healthcare workers regarding occupational exposure. This suggests that many healthcare workers may not have learned from previous exposures, which could also indicate insufficient training provided by hospitals. From another perspective, current control strategies are not yet sufficient to completely prevent occupational exposures caused by certain pathways (especially sharp injuries and needlesticks). Hospitals need to strengthen training for healthcare workers and develop updated control strategies.
Occupational exposure is commonly associated with the patient treatment process. In previous research, the challenges faced during treatment procedures are considered the greatest due to the limited space, poor visibility, and patient movements[19, 21, 23]. However, during our statistical analysis, we found that occupational exposures occurring during treatment procedures are only a part of the overall occupational exposure. Unfortunately, many occupational exposures also occur during instrument changes and after treatment. Our results show that the risk of repeated exposures during these three timings does not significantly differ. This implies that all three timings require healthcare workers' attention and caution. Further analysis of 81 ROEs incidents revealed that 49.4% of these occurred during the same timing as previous exposures(Fig. 1). Although this striking figure may be related to broad grouping in the study, it does reflect the level of occupational exposure risk during these three timings. Occupational exposures during instrument changes and after treatment are particularly concerning, which may be related to healthcare workers' attitudes and hospital training. Ensuring standardized procedures and protocols is crucial in reducing occupational exposure risks.
We believe that data on ROEs can guide the direction of infection control efforts in hospitals. Analyzing data on ROEs can help identify high-risk groups within the hospital for occupational exposures. Consequently, we can provide more targeted prevention education for individuals experiencing ROEs, which is advantageous for achieving better control of occupational exposures with limited resources. Targeted prevention and control training should involve intensifying training efforts for high-risk groups while providing more effective educational methods. Some studies suggest that solely providing occupational training or skill training may not effectively reduce the occurrence of occupational exposures[21]. Some conventional teaching methods often convey knowledge that is dry, difficult to understand, and not synchronized with clinical work[21]. Tailored prevention education for different groups is necessary; for instance, experienced doctors may not be engaged by generic educational materials. Research from Iran suggests that enhancing healthcare workers' perception of risks and understanding the severity of occupational exposure risks may be crucial for improving occupational exposure control[35].
ROEs may also indicate areas for improvement in equipment and operational processes. Previous research has indicated that using safer equipment and adopting safer operational procedures are undoubtedly beneficial for reducing occupational exposures[36, 37]. The occurrence of ROEs may indicate deficiencies in certain instruments or operational procedures in terms of safety. For example, research suggests that avoiding unnecessary use of sharp suturing needles can reduce needlestick injuries[38]. High-quality evidence demonstrates that using blunt needles significantly reduces the risk of surgical personnel and their assistants contracting infectious diseases during a series of surgeries by reducing the number of needlestick injuries[9]. This approach may also be applicable in dentistry. Furthermore, reducing occupational exposures occurring during non-treatment operations is also a critical area for consideration. Currently, researchers are also working on developing new medical waste disposal devices, instruments transfer, and retrieval devices in an attempt to reduce occupational exposures[39, 40]. Although ideal results have not yet been achieved, we believe that improving the usability and effectiveness of medical waste disposal devices may be a crucial pathway to reducing persistent occupational exposures.