A U-Net Approach to Apical Lesion Segmentation on Panoramic Radiographs

The purpose of the paper was the assessment of the success of an artificial intelligence (AI) algorithm formed on a deep-convolutional neural network (D-CNN) model for the segmentation of apical lesions on dental panoramic radiographs. A total of 470 anonymized panoramic radiographs were used to progress the D-CNN AI model based on the U-Net algorithm (CranioCatch, Eskisehir, Turkey) for the segmentation of apical lesions. The radiographs were obtained from the Radiology Archive of the Department of Oral and Maxillofacial Radiology of the Faculty of Dentistry of Eskisehir Osmangazi University. A U-Net implemented with PyTorch model (version 1.4.0) was used for the segmentation of apical lesions. In the test data set, the AI model segmented 63 periapical lesions on 47 panoramic radiographs. The sensitivity, precision, and F1-score for segmentation of periapical lesions at 70% IoU values were 0.92, 0.84, and 0.88, respectively. AI systems have the potential to overcome clinical problems. AI may facilitate the assessment of periapical pathology based on panoramic radiographs.

An overview of maxillofacial radiology education activities during and after the COVID- 19 pandemic

Objective: To convey the applications of online education in the field of maxillofacial radiology, which is widely used in the world during the COVID- 19 pandemic, and the post-pandemic education and training models suggestions in accordance with the changing world order by compiling the research results and literature information on the subject. Method: Different educational models applied in maxillofacial radiology before and during the COVID-19 pandemic were evaluated in terms of their results and activities by looking into published articles. In the light of these data, regulations, and recommendations were developed for post-pandemic educational activities. Findings: During the COVID-19 pandemic, the disruptions in educational activities at all levels and fields all over the world were reflected in maxillofacial radiology education. However, studies show that learning with online education in this field, especially in the interpretation of radiological images and problem-based learning activities, is at least as successful as or more than traditional education models. Online education also provides feedback to lecturers and promotes active learning, considered best practices for the teaching-learning process. During the COVID-19 pandemic period, theoretical education has been tried to be continued in the form of online education, although various some studies showed that online education is insufficient in practical education. In radiological interpretation, it is one of the biggest problems to ensure students' attention and effective participation in practical terms. In addition, online teaching of radiographic techniques and applications may not be as effective as instructive teaching techniques. After the pandemic, it is predicted that returning to normal maxillofacial radiology education will be challenging in both theoretical and practical aspects and there will is be a need to change. Results: Considering the strengths and weaknesses of online education models, whose application area has increased so much during the COVID-19 pandemic. The development and implementation of new, effective education-training models suitable both for the conditions and for everyone involved in education for the post-pandemic period, emerges as a necessity. After the pandemic, it is important to evaluate the blended education model in theoretical education, to make various changes in maxillofacial radiology practical training and to re-determine the rules of hygiene, separation and education.

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CBCT imaging and analysis was performed. Observe unilateral expansion by the distending soft tissue outline illustrated through 3D rendering (Figure 2). Sagittal oblique (Figure 3) and axial (Figure 4) slices depict a round heterogenous predominantly high-density lesion with an encompassing thin uniform less dense peripheral band. Irregular root resorption, displacement of the inferior alveolar nerve canal, buccal-lingual cortical expansion, thinning, and interruption was apparent. Irregular thickening at the inferior border and surrounding osteosclerosis were noted. A macroscopic view (Figure 5), photomicrograph (Figure 6), and conventional radiograph (Figure 7) of vertically sectioned surgical specimens of similar lesions. Note the intimate relationship with the tooth roots.

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A 64-year-old male patient, who is human immunodeficiency virus (HIV) positive on treatment, presented with atwo-year history of a painful swelling involving the left parotid gland. Cone beam computerised tomographic (CBCT) imaging was performed (Figures A-D). What are the pertinent radiological findings and your diagnostic hypothesis?

Prevalence of Impacted and Semi-Impacted Teeth and Determination of Impaction Angle of Teeth in Patients of Tooba Clinic, Sari, Iran in 2013-2019

Introduction: Impaction is one of the most common tooth abnormalities which has multiple pathological consequences. The purpose of this study is to assess the prevalence of impacted and semi-impacted teeth and to determine the impaction angle of different teeth in patients referred to the maxillofacial radiology department of dental school, Mazandaran University of medical sciences in years 2013-2019. Material and Methods: The panoramic radiographs of patients who were referred to oral and maxillofacial radiology department of Mazandaran dental school were observed. Impaction or semi-impaction angle of third molars were determined by Winter’s classification. Statistical analysis were conducted by using Chi-square test, Fisher’s exact test, Mann Whitney U test and Spearman correlation test (a= 0/05). Results: 3200 panoramic radiographs were analyzed, and the prevalence of impaction, complete impaction and semi-impaction were calculated to be 25/8%, 3/7% and 23/6% respectively. The mesioangular impaction (48/3%) was the most prevalent kind of impaction. Statistically, age was correlated with the jaw involving tooth impaction (P=0/01), this correlation wasn’t observed about sex (P=0/161). Conclusion: Impacted teeth were observed in approximately one third of the radiographs. Impaction was more common in the mandible and the most prevalent kind of impaction was determined to be the mesioangular impaction. As the impacted tooth can cause problems we conclude that they must be extracted at an early age.

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A 9-year-old female presented with a history of a firm painless bony swelling at the left mandible. A pantomograph (Figure 1) revealed a large radiopaque mass in the mandibular body with impaction of the 36. What are the most distinguishing radiological features and what is your provisional diagnosis?