Li Zhen Lim

Objectives: Panoramic radiographs (PANs) are a commonly used dental imaging modality and are complex to evaluate. This study aimed to use mouse-tracking technology to identify the visualization characteristics of experienced Oral & Maxillofacial Radiology (OMR) faculty when reviewing PANs and to assess relationships with detection accuracy. Methods: Seventeen OMR faculty in US dental schools with 5 to 38 years of experience were recruited. Participants were shown 17 PANs (5 “Normal” and 12 “Pathology”) over Zoom and instructed to move their mouse cursor in sync with their eye movements. Data collection was based on video recordings with X, Y coordinates auto-detected using mouse-tracking algorithms. Parameters collected included detection accuracy, time taken, completeness of search coverage, revisits and search patterns used. Results: Most common search patterns were Dental to Periphery (41.5%) and Periphery to Dental (37.7%). The mean accuracy score for all cases with pathology was 84.8%. Except for 2 cases with subtle findings (condylar fracture and fibrous dysplasia), mean accuracy scores ranged from 76.5% to 100%. There were no associations between search patterns and detection accuracy. Participants took longer durations and performed more complete searches with more revisits on “Normal” cases. They were more likely to use shorter search times with smaller coverage and perform single searches when correctly detecting lesions. Conclusions: Experienced OMRs were able to detect lesions without scanning the entire PAN and within a single search, regardless of the search pattern used. Advances in knowledge: This is the first study using mouse-tracking algorithms to evaluate visualization characteristics on PANs. Experienced OMRs can conduct efficient and accurate reviews of PANs regardless of search strategy.

Objectives: This survey was conducted to identify dental radiography practices and knowledge gaps among dentists in Singapore with respect to both 2D and 3D imaging. Methods: This was a cross-sectional survey conducted via an electronic platform from May to June 2023. All Singapore Dental Council-registered dentists were eligible to participate. We gathered data on demographics, intraoral (IO) radiography usage, cone-beam CT (CBCT) training, current CBCT usage, and interpretation. Results: Three-hundred and five out of 2605 registered dentists completed the online survey (11.7% response rate). Radiograph positioning holders, digital imaging, and round collimation were used by most respondents for IO radiography (85.6%, 88.9%, and 89.2%, respectively). One-hundred and forty-two participants (46.6%) underwent CBCT training, and most lacked training in image acquisition. Dentists expressed interest in CBCT interpretation and the use of viewing software; 219 dentists (71.8%) are CBCT users. Most (74.9%) took 0-5 CBCT scans monthly. Implant planning was the most common indication (24.8%). Among CBCT users, 85.9% report some or all their own scans while 70.7% would engage a reporting service if available. Conclusions: This survey provides insights in dental imaging that require increased educational efforts in Singapore. For IO radiography, there should be greater emphasis on rectangular collimation. With CBCT, there is potential for training in image acquisition, interpretation, and the use of viewing software. Advances in knowledge: Identifying knowledge and training gaps in dental imaging is critical to ensure the safe use of ionizing radiation on patients.

Interpreting radiographic lesions on dental radiographs is a challenging process especially for novice learners, and there is a lack of tools available to support this diagnostic process. This study introduced dental students to two diagnostic aids with contrasting reasoning approaches—ORAD DDx, which uses an analytic, forward reasoning approach, and a Radiographic Atlas, which emphasizes a non-analytic, backward reasoning approach. We compared the effectiveness of ORAD DDx and the Atlas in improving students’ diagnostic accuracy and their ability to recall features of radiographic lesions. Participants (99 third-year dental students) were assigned to ORAD DDx, Atlas and Control groups. In the pre-test and post-test, participants provided their diagnosis for eight types of radiographic lesions. All groups also completed a Cued Recall Test. Feedback about ORAD DDx and the Atlas was collected. Results indicated that the Atlas was more effective than ORAD DDx in improving diagnostic accuracy (Estimated marginal mean difference = 1.88 (95% CI 0.30–3.46), p = 0.014, Cohen’s d = 0.714). Participants in the Atlas group also outperformed the Control group in the recall of the lesions’ radiographic features (Estimated marginal mean difference = 3.42 (95% CI 0.85–5.99), p = 0.005, Cohen’s d = 0.793). Students reported that both ORAD DDx and Atlas increased their confidence and decreased the mental effort required to develop differential diagnosis (p ≤ 0.001). This study demonstrates the effectiveness of a non-analytic approach in interpreting dental radiographs among novice learners through the novel use of diagnostic aids.

Introduction: The COVID‐19 pandemic has necessitated an unprecedented shift from face‐to‐face teaching to e‐learning. Previous surveys revealed the negative impact of COVID‐19 on dental education and the physical and psychological well‐being of dental students. This qualitative study aimed to investigate the perspectives of dental educators towards e‐learning during the pandemic and the impact of this experience on their future adoption of e‐learning.Materials and Methods: Semi‐structured interviews with dental educators from the National University of Singapore were conducted over Zoom. Audio recordings were transcribed verbatim and subjected to thematic analysis. Data saturation was reached. Consolidated criteria for reporting qualitative research (COREQ) was followed.Results: Fifteen out of 22 (68%) eligible dental educators were interviewed. Educators had minimal prior e‐learning experience. They encountered difficulties in engaging students, assessing students' understanding and adapting their teaching. A practical challenge was to ensure the well‐rounded training of competent dentists with adequate patient‐interaction skills through e‐learning. Self‐motivation of the audience, class size, type of teaching and complexity of the material were perceived as factors influencing the suitability of the e‐learning format. Educators reported an increased confidence after this emergency e‐learning experience. Some considered sustaining or expanding e‐learning in their future teaching practice and highlighted the need for continued investment and institutional support, training on the pedagogy of e‐learning modalities and curriculum redesign to accommodate blended learning approaches.Conclusions: Although the shift to e‐learning during the COVID‐19 pandemic presented a myriad of challenges, dental educators gained experience and confidence which may accelerate the pace of future e‐learning adoption and innovation.

Objective: To investigate the differences in imaging characteristics and the diagnostic accuracy of 225 intraosseous jaw lesions on panoramic radiographs (PAN) versus cone beam computed tomography (CBCT). Methods: 225 sets of PAN and CBCT images with biopsy-proven histopathological diagnoses were retrospectively compared in terms of radiographic features and diagnostic accuracy. The imaging characteristics of PAN and CBCT were independently evaluated by two oral and maxillofacial radiologists who were required to answer 12 questions and provided up to three differential diagnoses with their confidence scores. Results: Odds ratios (ORs) were statistically significant for border cortication (OR = 1.521; p = .003) and border continuity (OR = 0.421; p = .001), involvement on neurovascular canals (OR = 2.424; p < .001), expansion (OR = 7.948; p < .001), cortical thinning (OR = 20.480; p < .001) as well as its destruction (OR = 25.022; p < .001) and root resorption (OR = 2.477; p < .001). Furthermore, imaging features in the posterior and mandibular regions showed better agreement than those in the anterior and maxillary regions, respectively. The diagnostic accuracy of the first differential diagnosis was higher on CBCT than on PAN (Observer 1:78.7 vs 64.4%; Observer 2: 78.7 vs 70.2% (p < .001)). The observers’ confidence scores were also higher at CBCT interpretation compared with PAN. Conclusions: CBCT demonstrated a greater number of imaging characteristics of intraosseous jaw lesions compared with PAN, especially in the anterior regions of both jaws and in the maxilla. Diagnostic accuracy is improved with CBCT compared to PAN, especially for lesions in the maxilla. Radiologists have greater confidence when using CBCT.

Due to the COVID-19 pandemic, eLearning became the lifeline of higher education. We explored university educators’ eLearning perspectives, practices, and future adoption intentions. In-depth interviews with 14 educators from a large university in Singapore were conducted. Educators had limited eLearning experience prior to COVID-19 emergency eLearning and expressed strong preferences for in-person sessions. The short notice to switch to eLearning and lack of eLearning experiences created stress and anxiety. Educators responded by making efforts that allowed for teaching to continue, conceding that some expectations had to be readjusted. Despite many obstacles, educators acknowledged reduced apprehension towards eLearning. Reflecting upon their experiences, educators highlighted opportunities and challenges of eLearning. A key opportunity was increased flexibility, which enabled students to learn independently. Additionally, eLearning triggered reflection upon educators teaching which could lead to improved practice. Reduction of some barriers to student–educator interaction were also mentioned. Key challenges include creating social, emotional, and cognitive engagement, catering to diverse student needs and providing holistic learning experiences. Considering opportunities and challenges, educators envisioned that eLearning would feature in their future teaching if practical and helpful for achieving educational goals. Hybrid or blended learning approaches were preferred, but support enabling the implementation of technology-based and pedagogy-informed teaching is necessary.

Objectives To investigate the predictive value of carotid artery calcifications (CACs) seen on dental imaging for future adverse events related to cerebrovascular and cardiovascular diseases. Methods Electronic databases (PubMed, Embase, SCOPUS and Cochrane) and selected grey literature were searched. Outcomes included stroke, transient ischaemic attack (TIA), myocardial infarction (MI), angina, heart failure, future interventional revascularization procedures and death. Risk of bias was assessed using the Newcastle-Ottawa Scale. Results 5 studies were selected from 1011 records. All were of moderate to low risk of bias. Results were heterogeneous but showed that patients with CACs on panoramic radiographs (PANs) were more likely to experience strokes, TIA, MI and future revascularization procedures compared to control groups. The differences between groups were not all found to be statistically significant. Bilateral vessel-outlining CACs were an independent risk marker for future vascular events. Patients who are not currently being managed for cardiovascular risk factors should be referred for further evaluation. Those already being treated for atherosclerosis may not benefit from additional investigations. Conclusion The evidence for the predictive value of CACs on PANs for adverse future vascular events is equivocal but can help to identify at-risk patients who require further evaluation. Clinical relevance Dentists must be able to recognize CACs on PANs and make appropriate referrals for patients to be evaluated for cardiovascular risk factors, especially those who have not previously been assessed.

Purpose To systematically evaluate the diagnostic efficacy of intraoral radiographs and evidence supporting the indications for taking of intraoral radiographs in children in the following five clinical categories: caries, pathological conditions (including acute odontogenic infections and periodontal disease), dental/developmental anomalies, dental trauma, and enhancement of comfort/technique for taking radiographs in children. This was carried out to facilitate the updating of existing European Academy of Paediatric Dentistry (EAPD) guidelines on dental radiography in pediatric dentistry. Methods A systematic electronic literature search was conducted on Cochrane Library (1992–24 July 2018), MEDLINE (PubMed, 1946–24 July 2018), EMBASE (Embase.com, 1974–24 July 2018) and Scopus (pre-1970–24 July 2018). Hand search of handbooks and grey literature search was also performed. Study screening and study inclusions were agreed upon by three authors. Data extraction, and methodological quality and risk of bias assessment were carried out in duplicate for each of the included studies. Results A total of 9581 papers were identified. Following the primary and secondary assessment process, 36 papers were included in the final analysis. The included studies were further categorized into five main clinical categories for analysis: caries, pathological conditions, dental/developmental anomalies, dental trauma and comfort/technique-related studies. Only one paper was found to be of good quality and at low risk of bias; while, 9 papers were found of be at moderate risk of bias and 26 papers were at high risk of bias. Meta-analysis was not possible for any of the aforementioned clinical situations, and only a narrative synthesis was done. Conclusion There is insufficient high-quality evidence for the use of intraoral radiographs in pediatric dentistry and current guidelines are based largely on expert opinion. There is a clear need for well-conducted and standardized studies regarding the use of intraoral radiography in pediatric dentistry.