Patient safety incidents in dentomaxillofacial imaging: reported adverse events from Hospital District Helsinki and Uusimaa and the City of Helsinki during 2012–2017

Patient safety in medical care has become a hot topic of research, particularly since the publication of To Err is Human in 2000 [1]. More recently, this patient safety focus has broadened to dentistry, including dentomaxillofacial radiology (DMFR). The role of imaging devices related to patient safety incidents (PSI) in dentistry, however, remains sparsely studied. Most device-related, safety-based studies in DMFR are about different dental materials and their compatibility with MRI, focusing on the different magnetic flux densities of 1.5 T, 3 T, and 7 T [2‐4].

In contrast, many radiation protection studies in DMFR have been reported. Some of these note that different features of two-dimensional (2D) imaging devices have a positive effect on patient safety by providing diverse imaging protocols, better shielding options, and advanced technical features [5, 6]. All of these attributes, either by themselves or when used according to the basic radiation protection principle ‘ALARA’ (as low as reasonably achievable), reduce patients’ radiation dose. In addition to these new, more advanced conventional panoramic and cephalometric imaging devices, the introduction of three-dimensional (3D) cone beam computed tomography (CBCT) to dentistry in the late 1990s has had an indisputable impact on DMFR. CBCT provides great versatility to oral radiology, which explains the steady rise in the number of dental CBCT devices all over the world, including Finland [7‐9].

Reporting patient safety incidents (PSI) related to medical devices and materials is similar to other European Union member states [10‐12]. In Finland, these adverse events (AE) were previously reported to the National Supervisory Authority for Welfare and Heath (Valvira), but its operations concerning medical devices have been transferred to the Finnish Medicines Agency (Fimea) at the beginning of 2020 [13]. In Finland, voluntary reporting of other PSI is strongly advised and the most widely used tool for this is HaiPro. HaiPro is an anonymous web-based tool intended for healthcare professionals to report PSI. It is used by over 200 social service and healthcare organizations varying from small healthcare centers to entire hospital districts, and both Hospital District Helsinki and Uusimaa (HUS) as well as the City of Helsinki (HKI) use it [14].

HUS covers the Finnish capital region and multiple other municipals of Southern Finland, with approximately 1.55–1.65 million inhabitants during 2012–2017, while HKI had approximately 600,000–650,000 inhabitants [15‐18]. In HUS and HKI during 2012–2017, a total of 931,094 dental radiographs were taken, of which 201,113 (22%) were taken in HUS and 729,981 (78%) in HKI (Fig. 1). The large difference in these numbers is mainly because HUS provides secondary care services, while HKI provides primary care services.

Although dental imaging has a long history, data on patient safety incidents in dentomaxillofacial imaging are minimal both at the national and international levels. Thus, their contributing and mitigating factors remain unclear, which calls for research on the subject worldwide. The lack of identifying and reporting patient safety incidents or adverse events that are related to DMFR can also hinder healthcare organizations to achieve and maintain a high level of patient care quality.

The aim of this study was: (1) to identify and categorize PSIs in DMFR as well as their outcome in Southern Finland; (2) to evaluate how well these adverse events are detected and reported by healthcare workers; and (3) to determine whether the rapid increase in CBCT imaging has had any effect on the PSIs.

Finnish national law does not require ethics committee approval for registry studies with no patient intervention involved [19], but the required permission from the Research Administration of HUS and HKI was obtained for this study. We gained access to the whole HaiPro-data from HUS (HUS-data), but the HaiPro-data from HKI (HKI-data) were restricted to reports related to dentistry and reports related to diagnostics, which consisted of medical imaging and laboratory services. Notifications related to medical imaging were unavailable in the same matter in the HKI-data as in the HUS-data, because medical imaging was not listed as its own entity in the HKI-data. In HKI-data, imaging-related reports were combined with laboratory-related reports under the heading “Diagnostics.” Oral healthcare was implemented as its own entity in both data systems since the beginning of 2015.

HaiPro, the patient safety incident report, consists of multiple fields that specify the recognized PSI and its circumstances, including the department of the person filling the report, the department where the incident happened, and the occupational role of the reporter. Occupational roles include nurses, doctors, midwifes, and many more. The report also contains fields for the date and time of the incident, the nature of the incident, incident type, and description of the incident and its possible contributory factors. The nature of the incident can be defined as a near miss, as an actual incident or as another observation related to patient safety. The incident type is selected from a list of choices clarifying whether the incident is related to medication, flow, or control of information, to a diagnosis, a machine or its usage, or unknown—just to name few. The outcome and its severity to the patient, as well as to the department where the incident happened, and a risk classification of the event are also estimated by the reporter. Additional fields are for information about the measures taken, as well as for suggestions to prevent similar incidents in the future. The classification criteria of the HaiPro-system are similar—yet not identical—to the International Classification for Patient Safety (ICPS) published by the World Health Organization (WHO) [20].

We searched both databases for the reports filed in 2012–2017 using the search tool integrated in the HaiPro-system. The text search tool can search for keywords or abbreviations through either the whole database or under preset headings. We used multiple keywords and abbreviations consisting of the most commonly used Finnish terms in dentistry and DMFR, which are listed in Table 1. The differences between the chosen keywords in both data systems were due to the use under preset headings and the aforementioned structural differences in the HUS-data compared to the HKI-data. Additionally, all dentistry-related PSI reports, as well as those found with the keyword search, were evaluated individually to avoid missing any DMFR-related reports. Due to our partly keyword-based and partly manual screening-based search, duplicates were found and excluded. Keyword search revealed cases that were not related to DMFR, e.g., ‘Oral’ cancer or ‘dental’ trauma-related PSI as well as musculosceletal CBCT-related PSI. Aforementioned PSI reports were excluded. Manual screening of all dentistry-related PSI was performed by an oral and maxillofacial radiologist (MS). Any cases that were questionable regarding their inclusion/exclusion were discussed by all authors. PSI that were generally related to radiology or its ICT environment were included. The data were collected during 10.6.–12.6.2019 (HKI) and 2.7.–4.7.2019 (HUS), and the detailed process is shown in Fig. 2. We decided to include 2012–2014, in addition to 2015–2017, in our evaluated time-period to be able to determine if the reporting activity had grown over the years (Fig. 3). Opting for these years, we were also able to compare the results of an equal time-period before and after oral healthcare was implemented as its own entity in these data systems.

We compartmentalized all found DMFR-related PSI by their type accordingly to the HaiPro classification system. The event type was categorized to be related to:

Furthermore, we assessed the contributing factors of the PSI, which were categorized being related to:

The nature of these main categories was further evaluated and reported in detail, including their risk classification, severity, outcome, and possible corrective actions.

None of the gathered information consists of data that could lead to identifying neither healthcare professionals nor patients.

In the HUS and the HKI, a total of 195,593 HaiPro-reports were filed in 2012–2017. In HUS, the total number of these reports was 93,176, of which 1.614 (about 2%) were related to medical imaging and only 359 (about 0.4%) were related to dentistry and in HKI the total amount of the reports was 102,417, of which only 61 (about 0.06%) concerned dentistry (Fig. 4). In the HKI-data, medical imaging-related reports were not available separately categorized comparable to the HUS-data. Altogether, 420 dentistry-related PSI and 2464 PSIs that matched our keyword search, from both HUS and HKI, were evaluated individually not to miss any DMFR-related reports. We found 43 reports of DMFR-related PSIs, of which 35 were from the HUS-data and 8 from the HKI-data (Fig. 5).

In our study, the amount of reported PSIs compared to the number of dental radiographs taken in their corresponding organizations stand for approximately 0.02% in HUS (35/201,113) and 0.001% in HKI (8/729,981).

Adverse events related to DMFR are rarely reported and the number of reports seems extremely low compared to the number of dental radiographs taken. In 2015, approximately 3.9 million radiological examinations and 1.9 million dental radiographs were obtained in Finland, stating that about 33% of all radiological examinations were related to DMFR [21]. In our data, when we compare the amount of reported PSI related to DMFR (35) and medical imaging (1.614) in secondary care, there is a notable discrepancy between them as DMFR-related PSI represent only about 2% of all medical imaging-related PSI. It is also notable that even though the number of dental radiographs from HUS in comparison to HKI was only about 28% (201,113/729,981), the number of reported PSI from HUS compared to HKI is greater by almost 440% (35/8). These raise the question of whether there are unidentified profession-related (dentistry vs. medicine) or organizational-related factors that explain the aforementioned diverse reporting activity, especially when comparing healthcare professionals working in secondary care to those working in primary care. One possible explanation could be that patient safety culture has a more solid foundation in secondary care. As a secondary care provider, HUS has been actively promoting patient safety over the past decade and it has been a focus of vivid research, for example, the doctoral dissertation of Palojoki S. in 2017 focusing on understanding and thus preventing technology-induced errors in electronic health records, and that of Tolvi M. in late 2020 focusing on the Weekend Effect and Readmissions in HUS [22, 23]. An upsurge in research focusing on patient safety in primary care since 2001 was found by R. Spencer and S. Campbell (2014), although primary care patient safety studies lag behind those for secondary care patients [24, 25]. As HKI followed by HUS, are the two largest employers in Finland and their staff is most likely a quite homogenous group of healthcare professionals regarding their education, working culture, and the use of the same reporting tool for PSI, additional studies are needed to reveal why the reporting activity is considerably lower in primary care. Comparing the qualities of these organizations’ patient safety cultures might also highlight some potentially effective tools for engaging healthcare professionals as active promotors for a better patient safety culture.

This study revealed that patient safety incidents in DMFR are seldom reported and that their outcome to the patient as well as to the organization was mostly considered irrelevant or minor. Our finding of DMFR-related PSI resulting only rarely in severe harm for the patient is consistent with the findings documented by Kasalak Ö. et al. regarding radiology related PSI [26]. Worryingly, even in our small dataset, almost 7% of reported cases revealed a mix-up between patients, which ultimately could lead to severe harm to a patient, especially in secondary care. This finding accentuates the importance of educating oral and other healthcare professionals to use at least two identifiers as stated by WHO when verifying the patient’s identity [27]. This mix-up of patients was also detected by Jämsä J. et al. in their study of differences regarding serious and nonserious PSI reported in the Hospital District of Helsinki and Uusimaa (HUS) [28]. They reported that of the specific types of PSI within serious incidents, the most important was related to laboratory-, medical imaging-, or other patient examination manifesting as samples taken from the wrong patient. In addition, their study revealed that the third most important incident type within the serious incidents was due to equipment malfunction, but their data did not reveal if or how medical imaging devices contributed to this incident group.

In regard to our results, we find that the most important finding of our study is our suspicion of that a considerable number of PSIs regarding DMFR are left unreported by healthcare professionals, although reporting of all noticed PSIs is officially recommended, and even mandatory when related to the use of ionizing radiation in medicine [29]. This also seems to be in accordance with the observation that even after more than a decade since the publication of To Err is Human, a vast majority of all hospital-based errors, accidents, and other adverse events still go unreported by healthcare professionals [30]. In her doctoral thesis in 2016, Hiivala showed that underreporting PSIs and AEs in dentistry has been suspected in numerous preceding publications [31]. Polisena and colleagues (2015) explain that reasons for this vary, as shown by in their systematic review indicating that uncertainty of what should be reported, the fear of punishment, and time constraints are common barriers to the recognition and reporting of adverse events [32]. In Hiivala’s thesis, the reasons for dentists not to report AEs were in accordance with those indicated by Polisena and colleagues [31, 32]. We also question whether the possible AEs are accurately identified and if the reporting process is familiar to the healthcare workers.

In our data, 25% of all reported events were related to CBCT imaging, which could be related to the fact that it is a relatively new imaging modality and a more complex mechanical device in comparison to the more common panoramic and cephalometric imaging devices. This remains unclear, though, and more research is needed to enlighten the patient safety aspects that might be unique to the CBCT imaging modality.

The limitations of this study lie in the relatively short evaluation period, especially as dentistry was implemented as its own entity in the HaiPro databases only recently, in 2015. In addition, the use of a free-text search tool is prone to miss a finding because of typos. To minimize this factor, we executed a systematic and thorough evaluation of all reports that matched our keywords and those related to dentistry in order not to miss any DMFR-related reported patient safety incidents. To the best of our knowledge, patient safety in dentomaxillofacial radiology in combination with differences between primary and secondary care has not yet been studied, and thus, the main strength of this study is its novelty.

Education, as well as clinical audit, emphasizing patient safety related to medical devices in the field of DMFR would probably be useful to inform and to remind healthcare professionals to report patient safety incidents. It might also be beneficial to implement patient safety as its own distinct entity in dental studies, to raise awareness in the field. Although Künzle et al. focused on leadership in critical care teams in their literature review, their conclusion of the pivotal role of effective leaders in promoting team performance and safety raises the question whether this is lacking in dentistry [33]. Finnish dentists work quite independently in primary health care and in the private sector, too, but in secondary care dentists are more commonly part of a team. Perhaps, this and the subsequent lack of leadership explain some of the difference seen in the reporting activity between primary and secondary healthcare, in addition to the aforementioned suspicion of a more solid foundation of the patient safety culture in secondary care. More research is needed to provide information whether DMFR-related AEs are truly left unreported and what are the actual reasons behind the great difference in reporting activity between primary and secondary healthcare workers concerning DMFR.