Viewing patterns regarding panoramic radiographs with different pathological lesions: an eye-tracking study

OBJECTIVE: The aim of this study was to examine how dental students vary their viewing patterns of panoramic radiographs during different levels of dental education. METHODS: Two groups of students (total number = 48, n = 24) in different grades (second and fifth clinical semester) were compared. The second clinical semester participated twice, as during the second clinical semester a specific lecture on dental radiology and diagnosis is held. The first viewing took place at the beginning of the semester (2a), the second at the end of it (2e). The fifth semester (5e) represents students shortly before graduation. While viewing 20 panoramic radiographs showing specific pathologies, the eye movement was captured by an eye-tracker. After a maximum of 60 s per image, the students had to report a suspected diagnosis. Every panoramic radiograph included a pathological lesion which was diagnosed by an expert observer who also defined the areas of interest (AOI). The images were presented in the same order to each participant. The metric data recorded by the tracking-system included total time to first fixation, total fixation count, total gaze duration and coordinates of the fixation in and outside an area of interest. In addition, parameters like the completeness of scanning and the suspected diagnosis were analysed. Differences between the groups were assessed for statistical significance and associations between level of different grades, viewing time, completeness of scanning and correctness of diagnosis were computed. RESULTS: 2e was significantly faster (p < 0,001), whereas 5e was significantly (p < 0.001) more likely to diagnose correctly and also to scan more completely. Scanning duration did not significantly influence the correctness of diagnosis. The lower edges of the panoramic radiographs were not scanned as often as the centre of the image. Bony lesions were generally found to be difficult to interpret and significant findings located in the sinus were overlooked the most. CONCLUSION: The higher semester had a more complete viewing pattern and diagnosed correctly with a higher percentage. After hearing the mentioned lecture, the second semester scanned faster and mentioned the AOI more often but could not make a right diagnosis.