Effect of radiotherapy on the surface roughness and microhardness of contemporary bioactive restorative materials.

OBJECTIVE: The aim of this in vitro study was to evaluate the effect of radiotherapy on the surface microhardness and roughness of different bioactive restorative materials. MATERIALS AND METHODS: A total of 60-disc specimens (5 mm × 2 mm) were performed in four groups (n = 15 each) from Equia Forte HT, Cention N, Activa Bioactive Restorative, and Beautifil II. Following the polishing procedure (600, 1000, 1200 grit silicon carbide papers), all specimens were irradiated at 2 Gy per fraction, five times a week for a total dose of 70 Gy in 30 fractions over 7 weeks. Before and after the irradiation, the specimens were analyzed regarding the surface roughness and microhardness. Surface morphology was also analyzed by scanning electron microscopy. Kruskal-Wallis test, Wilcoxon test, and paired sample t-test were used for statistical analysis. RESULTS: Significant differences were found after radiation with increased mean roughness of both Cention N (p = 0.001) and Beautifil II (p < 0.001) groups. In terms of microhardness, only the Beautifil II group showed significant differences with decreased values after radiation. There were statistically significant differences among the groups' roughness and microhardness data before and after radiotherapy (p < 0.05). CONCLUSION: The effect of radiotherapy might differ according to the type of the restorative material. Although results may differ for other tested materials, giomer tends to exhibit worse behaviour in terms of both surface roughness and microhardness. CLINICAL RELEVANCE: In patients undergoing head and neck radiotherapy, it should be taken into consideration that the treatment process may also have negative effects on the surface properties of anti-caries restorative materials.

Radiation-induced xerostomia and cariogenic dietary habits.

PURPOSE: Despite the availability of various prevention methods, dental caries continue to be diagnosed in patients receiving head and neck radiotherapy (RT). Since conventional approaches do not evaluate posttreatment alterations in dietary behaviors, we aimed to assess the influence of radiation-induced xerostomia on post-RT cariogenic dietary habits in patients. METHODS: Fifty-seven patients completed the Xerostomia Questionnaire (XQ) and answered questions regarding daily cariogenic food and beverage (CFB) intake, daily tooth brushing, fluoride application, and subjective total taste acuity (STTA). They also underwent evaluations to determine the Simplified Oral Hygiene Index (OHI-S) score, Saxon test score, number of decayed-missing-filled teeth (DMFT), and proportion of DMFT to the test teeth (DMFT rate). Clinical records were searched for information regarding RT modalities, including the median of the mean dose to the parotid glands, days after the completion of RT, submandibular gland resection, whole-neck irradiation, and the DMFT value and rate before RT. The patients were divided into low and high XQ score groups based on the median XQ score of 47.5 for the two sample tests. Univariable and multivariable regression analyses were used to identify independent factors for frequent CFB intake. RESULTS: Higher XQ scores were associated with a significantly greater frequency of CFB intake (p = 0.028*). Regression analysis also identified a higher XQ score (p = 0.017*) as an independent risk factor for frequent CFB intake. CONCLUSION: Radiation-induced xerostomia increased the frequency of CFB intake.

Paediatric radiology training in the UK: a national trainee survey by the British Society of Paediatric Radiologists (BSPR).

AIM: To survey current UK radiology trainee experiences and opinions regarding the quality of paediatric radiology training encountered in their core years, and assess their career ambitions with regards to paediatric radiology. MATERIALS AND METHODS: A 22-question online survey, approved by the BSPR committee, was promoted over 12 months (1 February 2022 to 31 January 2023) across current radiology trainees and fellows via regional radiology training programme directors (TPDs), Junior Radiology Forum (JRF) trainee representatives, at BSPR Junior Forum webinar teaching sessions, and via social media/word of mouth. RESULTS: Eighty-three UK survey responses were received from 17/19 (89%) training schemes. Sixty of the 83 (72%) had taken or were due to take a 2-4 month core paediatric radiology placement partly at tertiary centres (66/83, 80%), with 67/83 (81%) receiving dedicated didactic teaching. Only 26/83 (31%) reported fulfilling core curriculum competencies and 32/83 (39%) reported not receiving enough paediatric radiology training. Almost a quarter (18/83, 22%) reported <2 months of paediatric radiology rotation during core training and 12% (10/83) across six training schemes, reported no dedicated paediatric teaching sessions. Respondents who left negative comments around their experience were more likely to reject paediatric radiology as a future career option (p<0.05). CONCLUSIONS: Only 31% of UK radiology trainees reported having enough paediatric radiology training to achieve core competencies. Standardised training, teaching, and increased on-call support could improve confidence in dealing with emergency cases and encourage interest in paediatric radiology beyond junior years.

Planetary health: an imperative for pediatric radiology.

The global temperature has been increasing resulting in climate change. This negatively impacts planetary health that disproportionately affects the most vulnerable among us, especially children. Extreme weather events, such as hurricanes, tornadoes, wildfires, flooding, and heatwaves, are becoming more frequent and severe, posing a significant threat to our patients' health, safety, and security. Concurrently, shifts in environmental exposures, including air pollution, allergens, pathogenic vectors, and microplastics, further exacerbate the risks faced by children. In this paper, we provide an overview of pediatric illnesses that are becoming more prevalent and severe because of extreme weather events, global temperature increases, and shifts in environmental exposures. As members of pediatric health care teams, it is crucial for pediatric radiologists to be knowledgeable about the impacts of climate change on our patients, and continue to advocate for safe, healthier environments for our patients.

Is online-only learning as effective as blended learning? A longitudinal study comparing undergraduate students' performance in oral radiology.

INTRODUCTION: Blended learning seems to be an effective teaching concept in oral radiology. During the COVID-19 pandemic, blended learning shifted towards online-only learning. The aim of the present study was to compare the effectiveness of pandemic online-only and pre-pandemic blended learning in three consecutive oral radiology courses (C1, C2 and C3) and to examine whether additional video-based e-learning modules (VBLMs) had a positive impact on undergraduate students' performance during pandemic semesters. MATERIALS AND METHODS: Data from 205 undergraduate dental students participating either in a blended learning or an online-only learning concept were analysed. Pre-pandemic blended learning comprised face-to-face seminars and access to an oral radiology platform (ORP). Pandemic online-only learning comprised online seminars, access to the ORP and additional VBLMs (two VBLMs for C1, four VBLMs for C2 and six VBLMs for C3). Through standardised e-exams at the beginning and end of each semester, performance in final exams and knowledge gain were compared between the two groups. RESULTS: No significant differences in scores in final exams (p = .11) and knowledge gain (p = .18) were found when comparing the pre-pandemic and pandemic groups. On course level, however, students receiving a lower number of VBLMs performed significantly worse in final exams (C1: p < .01, C2: p = .02) and showed inferior knowledge gain (C2: p < .01) during the pandemic. CONCLUSIONS: Within the limitations of the study, the present investigation confirmed that pandemic online-only learning involving VBLMs might be as effective as pre-pandemic blended learning.

Students' perceptions of post-exam feedback in oral radiology-A comparative study from two dental hygienist educational settings.

INTRODUCTION: The aim of this study was to investigate how students perceive the benefit of participating in a teacher-organised session providing feedback on exams, termed post-exam feedback, in two dental hygienist programmes. METHODS: The study was based on interviews with 22 participants, including 18 students and 4 faculty teachers. The data were approached on the basis of thematic analysis, allowing us to generate insights on how the participants reflected on their participation in the post-exam feedback sessions and how they perceived this arrangement as learners. RESULTS: The findings from the study suggest that motivated students consider post-exam feedback to be beneficial in clearing up uncertainties and deepening their understanding of issues not fully understood during the exam, as well as supporting their further learning. Less motivated students mainly consider post-exam feedback to be relevant for students who do not pass the exams. CONCLUSIONS: Organised in a student-centred way and with attentiveness to student learning preferences, the results suggest that post-exam feedback can be valuable for enhancing assessment and supporting student learning related to exams.

[Efficacy and radiology evaluation of pulpotomy in mature permanent teeth].

OBJECTIVE: To observe the clinical efficacy of pulpotomy in patients of different ages and to explore the occurrence and characteristics of pulpal calcification. METHODS: A total of 77 patients who underwent pulpotomy for mature permanent premolars and molars with caries-derived pulp exposure in the Department of General Dentistry, Peking University School and Hospital of Stomatology from October 2019 to August 2022 were selected. Pulpotomies were performed in a single visit using iRoot BP Plus bioceramic material as pulp capping agent. The patients were divided into three groups according to age: 25 cases in the adolescent group (11-20 years old) with a mean age of (15.88±2.19) years; 27 cases in the middle-aged group (21-50 years old) with a mean age of (34.59±8.67) years; and 25 cases in the elder-aged group (51-83 years old) with a mean age of (63.84±7.40) years. The patients were reviewed 1 year after the operation to evaluate the clinical efficacy and to record the formation of calcified bridge, thickness of calcified bridge, and pulp calcification index (PCI). RESULTS: There was no statistically significant difference between the three groups in terms of gender, dentition, and tooth position (P > 0.05). The 1-year postoperative follow-up rate was 85.71% (66/77), including 88.00% (22/25) in the adolescent group, 85.19% (23/27) in the middle-aged group, and 84.00% (21/25) in the elder-aged group. The 1-year follow-up clinical success rates of the three groups were 95.45% (21/22), 91.30% (21/23), and 95.24% (20/21), respectively, with no statistically significant difference (P>0.05). Among the clinical success cases, calcified bridges appeared in 12 cases (57.14%, 12/21) in the adolescent group, 8 cases (38.10%, 8/21) in the middle-aged group, and 3 cases (15.00%, 3/20) in the elder-aged group, with statistically significant differences (χ2= 7.810, P = 0.020 < 0.05). The difference was statistically significant (F = 4.434, P = 0.020 < 0.05) when comparing the thickness of calcified bridges among the three groups. Calcified bridge thickness was negatively correlated with age (r = -0.516, P < 0.05). The changes in pulpal calcification index ΔPCI were 0.67 ± 0.58, 0.43 ± 0.51, and 0.25 ± 0.52, respectively, with statistically significant differences among the three groups (F = 3.404, P = 0.040 < 0.05). CONCLUSION: Pulpotomy for caries-derived pulp exposure in elderly patients could also achieve a high success rate. The incidence of calcified bri-dges after pulpotomy and the acceleration of pulpal calcification were age-related. The adolescent group was more likely to form calcified bridges and also showed more pronounced accelerated root canal calcification.

Patient Exposure from Radiologic and Nuclear Medicine Procedures in the United States and Worldwide: 2009-2018.

The U.S. National Council on Radiation Protection and Measurements (NCRP) conducted a retrospective assessment of the U.S. data, and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) performed a similar worldwide assessment for 2009-2018 (with most data from 2014 to 2017). Using the data from those reports, the frequency of radiologic and nuclear medicine studies, annual collective, and per capita effective dose in the United States for 2016 were compared with worldwide estimates from 2009 to 2018. There were an estimated 691 million radiologic, CT, dental, and nuclear medicine studies performed in the United States in 2016, which represented 16.5% of the 4.2 billion performed worldwide. The United States also accounted for 74 million CT procedures (18% of the world's estimated total), 275 million conventional radiology procedures (11% of the world's total), 8.1 million interventional radiologic procedures (34% of the world's total), 320 million dental radiography procedures (29% of the world's total), and 13.5 million nuclear medicine procedures (34% of the world's total). The U.S. collective effective dose was 717 000 person-sieverts (17.6% of the world's total). The average annual individual effective dose in the United States was 2.2 mSv compared with 0.56 mSv worldwide. The United States accounts for a large and disproportionate share of global medical radiation procedures and collective effective dose, but use of CT has increased more in other countries compared with the United States.

Sodium-hyaluronate mouthwash on radiotherapy-induced xerostomia: a randomised clinical trial.

INTRODUCTION: Radiotherapy-induced xerostomia (RIX) is one of the most common adverse effects of radiotherapy (RT) in head and neck cancer patients (HNC) and a major determinant of survivors' quality of life. The primary objective was to evaluate the reduction of patients' xerostomia symptoms after the utilisation of a sodium-hyaluronate mouthwash compared to a placebo solution. The secondary objectives were to evaluate the improvement of quality of life and to evaluate the patients' satisfaction. METHODS: The protocol was approved by the ethical committee (Ref. 50,053/19) and registered at ClinicalTrials.gov (ID: NCT05103124). The study was a double-blind randomised clinical trial (RCT) with a crossover design and was conducted at the Fondazione Policlinico Universitario A. Gemelli, Rome. RESULTS: Thirty-two patients completed the study protocol. Lower values of the modified Xerostomia Questionnaire (XQ) were retrieved when comparing the baseline scores to the ones after the treatment, when compared with placebo (Mann-Whitney U test = 0.01); higher values of patients' satisfaction (Likert scale) and modified XQ were retrieved for the sodium-hyaluronate mouthwash (Mann-Whitney U test = 0.001). CONCLUSIONS: This RCT highlights the advantages of treating RIX with the sodium-hyaluronate mouthwash since it seems to be clinically effective in reducing its symptoms, without any reported adverse events. CLINICALTRIALS: gov: NCT05103124 in 17/10/2021.

Management of radiation-induced oral mucositis in head and neck cancer patients: a real-life survey among 25 Italian radiation oncology centers.

AIM: Radiation-induced oral mucositis (RIOM) is the most frequent side effect in head and neck cancer (HNC) patients treated with curative radiotherapy (RT). A standardized strategy for preventing and treating RIOM has not been defined. Aim of this study was to perform a real-life survey on RIOM management among Italian RT centers. METHODS: A 40-question survey was administered to 25 radiation oncologists working in 25 different RT centers across Italy. RESULTS: A total of 1554 HNC patients have been treated in the participating centers in 2021, the majority (median across the centers 91%) with curative intent. Median treatment time was 41 days, with a mean percentage of interruption due to toxicity of 14.5%. Eighty percent of responders provide written oral cavity hygiene recommendations. Regarding RIOM prevention, sodium bicarbonate mouthwashes, oral mucosa barrier agents, and hyaluronic acid-based mouthwashes were the most frequent topic agents used. Regarding RIOM treatment, 14 (56%) centers relied on literature evidence, while internal guidelines were available in 13 centers (44%). Grade (G)1 mucositis is mostly treated with sodium bicarbonate mouthwashes, oral mucosa barrier agents, and steroids, while hyaluronic acid-based agents, local anesthetics, and benzydamine were the most used in mucositis G2/G3. Steroids, painkillers, and anti-inflammatory drugs were the most frequent systemic agents used independently from the RIOM severity. CONCLUSION: Great variety of strategies exist among Italian centers in RIOM management for HNC patients. Whether different strategies could impact patients' compliance and overall treatment time of the radiation course is still unclear and needs further investigation.

Comparative study of 360° virtual reality and traditional two-dimensional video in nonface-to-face dental radiology classes: focusing on learning satisfaction and self-efficacy.

BACKGROUND: Acquiring adequate theoretical knowledge in the field of dental radiography (DR) is essential for establishing a good foundation at the prepractical stage. Currently, nonface-to-face DR education predominantly relies on two-dimensional (2D) videos, highlighting the need for developing educational resources that address the inherent limitations of this method. We developed a virtual reality (VR) learning medium using 360° video with a prefabricated head-mounted display (pHMD) for nonface-to-face DR learning and compared it with a 2D video medium. METHODS: Forty-four participants were randomly assigned to a control group (n = 23; 2D video) and an experimental group (n = 21; 360° VR). DR was re-enacted by the operator and recorded using 360° video. A survey was performed to assess learning satisfaction and self-efficacy. The nonparametric statistical tests comparing the groups were conducted using SPSS statistical analysis software. RESULTS: Learners in the experimental group could experience VR for DR by attaching their smartphones to the pHMD. The 360° VR video with pHMD provided a step-by-step guide for DR learning from the point of view of an operator as VR. Learning satisfaction and self-efficacy were statistically significantly higher in the experimental group than the control group (p < 0.001). CONCLUSIONS: The 360° VR videos were associated with greater learning satisfaction and self-efficacy than conventional 2D videos. However, these findings do not necessarily substantiate the educational effects of this medium, but instead suggest that it may be considered a suitable alternative for DR education in a nonface-to-face environment. However, further examination of the extent of DR knowledge gained in a nonface-to-face setting is warranted. Future research should aim to develop simulation tools based on 3D objects and also explore additional uses of 360° VR videos as prepractical learning mediums.

A survey of patient contact shielding in dental teaching hospitals in the UK.

A high volume of dental imaging is carried out each year. In the UK, guidance on the use of patient contact shielding for these investigations is published by the British Institute of Radiology (BIR) and in a document jointly produced by the Faculty of General Dental Practice and Public Health England (FGDP/PHE). Both these sources of guidance have been updated recently and patient contact shielding is no longer recommended for most imaging settings in dental radiology. It is unclear whether radiology departments at dental teaching hospitals in the UK are aware of these sources of guidance, and how this relates to clinical practice within these departments. A survey was carried out exploring the awareness of current guidelines and clinical practice at dental teaching hospitals in the UK. The survey was sent to a representative at 17 different dental teaching hospital radiology departments. Responses were received from 11 departments. The range of intra-oral and extra-oral imaging carried out at these departments was comparable. Ten departments were aware of the existence of national guidelines for patient contact shielding, however only four were specifically aware of the recent BIR guidelines and only four were specifically aware of the FGDP/PHE guidelines. No department was aware of both sets of guidelines. No departments used thyroid protection for bitewing, periapical, lower 45 degree occlusal, panoramic or lateral cephalometric radiographs. Six departments sometimes or always used thyroid protection for upper standard occlusal imaging. Two departments used thyroid protection for cone beam CT imaging. No departments routinely used lead aprons on patients for dental imaging. In conclusion, radiology departments at dental teaching hospitals in the UK do not use patient contact shielding for most imaging situations in dental radiology. There is mixed awareness of current national guidelines, but the reported clinical practice aligns well with the current guidelines.

Fusion extracted features from deep learning for identification of multiple positioning errors in dental panoramic imaging.

BACKGROUND: Dental panoramic imaging plays a pivotal role in dentistry for diagnosis and treatment planning. However, correctly positioning patients can be challenging for technicians due to the complexity of the imaging equipment and variations in patient anatomy, leading to positioning errors. These errors can compromise image quality and potentially result in misdiagnoses. OBJECTIVE: This research aims to develop and validate a deep learning model capable of accurately and efficiently identifying multiple positioning errors in dental panoramic imaging. METHODS AND MATERIALS: This retrospective study used 552 panoramic images selected from a hospital Picture Archiving and Communication System (PACS). We defined six types of errors (E1-E6) namely, (1) slumped position, (2) chin tipped low, (3) open lip, (4) head turned to one side, (5) head tilted to one side, and (6) tongue against the palate. First, six Convolutional Neural Network (CNN) models were employed to extract image features, which were then fused using transfer learning. Next, a Support Vector Machine (SVM) was applied to create a classifier for multiple positioning errors, using the fused image features. Finally, the classifier performance was evaluated using 3 indices of precision, recall rate, and accuracy. RESULTS: Experimental results show that the fusion of image features with six binary SVM classifiers yielded high accuracy, recall rates, and precision. Specifically, the classifier achieved an accuracy of 0.832 for identifying multiple positioning errors. CONCLUSIONS: This study demonstrates that six SVM classifiers effectively identify multiple positioning errors in dental panoramic imaging. The fusion of extracted image features and the employment of SVM classifiers improve diagnostic precision, suggesting potential enhancements in dental imaging efficiency and diagnostic accuracy. Future research should consider larger datasets and explore real-time clinical application.

Three-Dimensional printed model for preclinical training in oral radiology.

INTRODUCTION: 3D printing is experiencing significant growth in the teaching and learning process. This study aims to present a 3D printed skull model for preclinical intraoral radiographic practice. MATERIALS AND METHODS: Two 3D printed mannequins were created. One mannequin used an STL file of a skull that was edited using two 3D modelling software (Meshmixer and Netfabb). The second mannequin was designed directly from a patient's segmented CBCT data and then converted into an STL file. Both mannequins were printed using fused deposition modelling (FDM) technology and polylactic acid (PLA) filament; teeth for the second mannequin were also printed using digital light processing (DLP). The printed skull bones were attached, the mandible was articulated to the articular fossa of the temporal bone, and the teeth were inserted into the alveoli. Intraoral radiographs of both mannequins were taken using a digital sensor (RVG 5100, Carestream). RESULTS: Both 3D printed mannequins showed satisfactory radiographic appearance, allowing geometric representation of each intraoral radiographic projection, regardless of STL file origin. Anatomical structures, such as the periodontal ligament space, zygomatic process of the maxilla and intermaxillary suture, were represented. The material cost of the first and second printed prototype was $34.00 and $39.00, respectively. CONCLUSIONS: The use of 3D printed models is presented as an alternative to artificial commercial phantoms for the preclinical training of intraoral radiographic techniques through the combined benefits of superior radiographic projection quality, the possibility of model manipulation and an affordable price.

The use of post-exam feedback in oral radiology: A survey study of dental and dental hygienist schools in Europe.

INTRODUCTION: A combination of summative assessments and post-exam feedback can create a formative environment to support student learning. It remains unknown to what extent feedback sessions are conducted after exams in oral radiology courses for dental and dental hygienist students in Europe. This survey study aimed to explore whether post-exam feedback sessions were conducted, and if so, in what format. MATERIALS AND METHODS: A questionnaire was distributed to 76 dental schools in 26 countries and 34 dental hygienist schools in 14 countries in Europe. The questions addressed whether feedback was provided after exams in oral radiology, the feedback format, and whether feedback sessions were formalised or performed for other reasons. RESULTS: Questionnaire responses were received from 33 dental schools in 18 countries, and 20 dental hygienist schools in 11 countries. Information about grades was provided in 23-30% of the schools. Post-exam feedback sessions including opportunities for discussion was provided at 39% of the schools, all with guidelines stating that these sessions should be carried out. The remaining schools provided feedback either on request by individual students or as written examples of correct answers. CONCLUSION: Almost one third of the dental schools announced grades without providing any post-exam feedback that could support learning. Two fifth utilised feedback sessions to assist students in gaining knowledge and sorting out misconceptions, all according to guidelines. Given the possible learning potential in post-exam feedback with opportunity to discuss, further studies of this format would be valuable, including the role and use of feedback guidelines.

ALGORITHM OF RADIOLOGICAL EXAMINATION OF PATIENTS IN THE PLANNING OF ORTHODONTIC TREATMENT OF INTERARCH RELATIONSHIP OF TEETH AND TEETH POSITION ANOMALIES.

OBJECTIVE: The aim: To increase the efficiency of diagnosis and planning of orthodontic treatment of patients with interarch relationship of teeth and teeth position anomalies by developing an optimal algorithm for radiological research using cone-beam computed tomography (CBCT), teleroentgenography (TRG), orthopantomography (OPG). PATIENTS AND METHODS: Materials and methods: 1,460 patients with interarch relationship of teeth and teeth position anomalies were examined at the Department of Radiology of the P. L. Shupyk National Healthcare University of Ukraine. The cohort of 1460 examined patients was divided by gender: 600 men (41.1%) and 860 women (58.9%) aged 6 to 18 years and 18 to 44 years. Distribution of patients was held by the number of the primary pathology signs and the number of concomitant pathology signs. RESULTS: Results: The choice of the optimal radiological examination of patients is influenced by the number of signs of the main and accompanying pathology. The risk of secondary examination of the patient with a mathematical method of choosing the optimal diagnostic technique is determined.The risk of secondary radiological examination of the patient was determined at a marginal probability of 88% (at a higher value, the model predicts a repeat visit). CONCLUSION: Conclusions: The developed diagnostic model shows that when determining the Pr-coefficient of 0.79, it is recommended to carry out OPTG and TRG. With indicators of 0.88, the recommendation is to conduct CBCT in the age groups 6-18 and 18-44 years.

Misconceptions about Oral Diagnosis and Radiology among Dental Students: A Questionnaire Study.

BACKGROUND: Misconceptions are learning deficits that may cause clinical judgments in a dental practice to be made incorrectly. AIM: This study aimed to identify and look into students' misconceptions regarding Oral Diagnosis and Radiology. MATERIALS AND METHODS: The fourth and fifth-grade students at the Altinbas University Faculty of Dentistry were given a self-administered questionnaire that included multiple-choice questions about Oral Diagnosis/Medicine and Radiology. 106 students participated in the questionnaire and 50.9% of the participants were fourth-grade students, 49.1% of them were fifth-grade students. The questions were classified into two parts: five scenario-based questions and ten knowledge-based questions. Students' replies were evaluated for accuracy and confidence, and when a student was certain of giving an inaccurate response, misconceptions were noted. Two groups were compared using the Mann-Whitney-U test (P = 0.05). RESULTS: A total of 1590 responses were collected. Regarding the question type, scenario-based questions had more misconceptions (19.6%) than knowledge-based questions (18.4%). Depending on the question, the majority of misconceptions were seen in the questions about denture stomatitis (46.2%) and radiographic contrast (38.7%). CONCLUSIONS: To prevent misdiagnosis, it is essential to recognize and overcome misconceptions in Oral Diagnosis/Medicine and Radiology. Therefore this study assists students and lecturers in defining misconceptions and organizing precautions to avoid and fix them.

Normal Variants of the Oral and Maxillofacial Region: Mimics and Pitfalls.

A normal variant is defined as an incidental, often asymptomatic, imaging finding that mimics a true pathologic condition. Given the complex anatomy and wide variety of normal variants in the oral and maxillofacial region, a thorough understanding of commonly encountered normal variants in this region is essential to avoid misinterpretation and unnecessary further imaging or interventions. Moreover, familiarity with normal variants that are known to become symptomatic at times is necessary to facilitate further workup and guide the treatment plan. Intraoral radiography and panoramic radiography, which are unique to oral and maxillofacial radiology, provide two-dimensional (2D) images. Hence, the overlapping of structures or the displacement of the tomographic layer on images can confuse radiologists. It is crucial to understand the principle of 2D imaging to avoid being confused by ghost images or optical illusions. In addition, understanding the normal development of the maxillofacial region is essential when interpreting maxillofacial images in children or young adults because the anatomy may be quite different from that of mature adults. Knowledge of changes in the jaw bone marrow and each tissue's growth rate is essential. It is also necessary to know when the tooth germ begins to calcify and the tooth erupts for diagnostic imaging of the maxillofacial region. The authors describe imaging findings and clinical manifestations of common normal variants in the oral and maxillofacial region, divided into four parts: the maxilla, mandible, tooth, and temporomandibular joint, and discuss the imaging approach used to differentiate normal variants from true pathologic conditions. Online supplemental material is available for this article. ©RSNA, 2022.

Application of WeChat-based flipped classroom on root canal filling teaching in a preclinical endodontic course.

BACKGROUND: This study was aimed to evaluate the application of WeChat-based flipped classroom in root canal filling teaching in a preclinical endodontic course. METHODS: A two-group comparative study was designed. The pre-class test, on-site quiz, and root canal filling on extracted premolars were performed by students from a lecture-based classroom group (LG, n = 30) and a WeChat-based flipped classroom group (WFG, n = 30). Results of the Pre-class test and on-site quiz were analyzed by independent samples t-test. Post-filling radiographs were taken and evaluated by a specialist in oral radiology who was blinded to grouping. Results of root canal fillings were analyzed by the Pearson chi-square test. Student responses in questionnaires were analyzed by Fisher's exact test. RESULTS: The students in WFG could get significantly higher scores in the on-site test and make better performances in root canal filling than those in LG. In terms of questionnaires, students from WFG were perceived to be more motivated to learn, better to understand the knowledge, better to improve communication and clinical skills, easier to perform root canal filling but spending more time. CONCLUSION: The WeChat-based flipped classroom teaching can have a better effect than lecture-based teaching on root canal filling learning for students with limited endodontic experiences.

Potential and impact of artificial intelligence algorithms in dento-maxillofacial radiology.

OBJECTIVES: Novel artificial intelligence (AI) learning algorithms in dento-maxillofacial radiology (DMFR) are continuously being developed and improved using advanced convolutional neural networks. This review provides an overview of the potential and impact of AI algorithms in DMFR. MATERIALS AND METHODS: A narrative review was conducted on the literature on AI algorithms in DMFR. RESULTS: In the field of DMFR, AI algorithms were mainly proposed for (1) automated detection of dental caries, periapical pathologies, root fracture, periodontal/peri-implant bone loss, and maxillofacial cysts/tumors; (2) classification of mandibular third molars, skeletal malocclusion, and dental implant systems; (3) localization of cephalometric landmarks; and (4) improvement of image quality. Data insufficiency, overfitting, and the lack of interpretability are the main issues in the development and use of image-based AI algorithms. Several strategies have been suggested to address these issues, such as data augmentation, transfer learning, semi-supervised training, few-shot learning, and gradient-weighted class activation mapping. CONCLUSIONS: Further integration of relevant AI algorithms into one fully automatic end-to-end intelligent system for possible multi-disciplinary applications is very likely to be a field of increased interest in the future. CLINICAL RELEVANCE: This review provides dental practitioners and researchers with a comprehensive understanding of the current development, performance, issues, and prospects of image-based AI algorithms in DMFR.