Utilizing a Novel AI Tool to Detect the Posterior Superior Alveolar Artery's Location's Impact on Maxillary Sinus Mucosal Thickening in the Presence of Periapical Lesions.

Periapical lesions have been implicated in sinus-related complications, but the precise influence of anatomical variations in the posterior superior alveolar artery (PSAA) on mucosal thickening remains an uncharted aspect. The new AI tool employed in this research utilizes advanced image processing algorithms to enhance image visualization. Background and Objectives: This study examines the accuracy of a new cone beam computed tomography (CBCT) software (eVol DXS, version 1.0.1.0) employing AI to detect the PSAA's location and the effect of that on maxillary sinus thickening in the presence of periapical lesions. Materials and Methods: This retrospective study included 120 CBCT cases with posterior maxillary periapical lesions and 120 without odontogenic infections. Teeth with proximity (<2 mm) to the sinus were excluded in both groups to eliminate the sinus floor's perforation effect. Both the PSAA locations and maxillary sinus thickening were classified and compared. Results: The mucosal thickening differs significantly (p < 0.001) between the study group and the control group. The study showed that an increased sinus thickness occurred when the PSAA was beneath the sinus membrane in the study group (62.5% compared to 8.6%; p < 0.001 *). The AI tool helped to achieve a 100% identification rate in determining the PSAA locations. Conclusions: AI algorithms for PSAA localization, which affects mucosal thickness in response to periapical lesions, yield excellent results.

Impact of Sequential Use of Reciprocating Files on the Shaping Load During Root Canal Treatment.

INTRODUCTION: The purpose of this in vitro study was to investigate the apical and coronal loads generated during shaping canals with 2 successive reciprocating files in comparison to a single reciprocating file from the same system. METHODS: A total of 40 narrow and straight canals were distributed into two groups: R-Motion with single file (RMS) and R-Motion with multiple files (RMM). In both groups, the R-Motion system was used in a reciprocating motion. After establishing glide path, the RMS canals were shaped down to working length with a single file (25/.06) in two insertions while the RMM canals were shaped with two files (20/.04 and 25/.06) to the working length. The shaping time and effects of tested groups on the apical and coronal peak loads were statistically analyzed using the t-test and Mann-Whitney U test, respectively, at a 95% confidence level. RESULTS: All canals were completely shaped in three insertions and no file deformation or fracture was observed. The RMS and RMM were able to shape canals in 117.3 ± 15.1 and 123.7 ± 7.3 seconds, respectively (P < .05). Within each group, the shaping load appeared to increase with the successive insertions of the file. In both groups, the ranges of apical and coronal peak loads were 0.41-1.87 N and 0.38-1.03 N, respectively. The RMM and RMS had comparable apical and coronal peak loads (P > .05) except in the last insertion where RMM showed clearly lower apical peak load than RMS (P < .01). CONCLUSIONS: Under the current laboratory conditions using the R-Motion system, preshaping the canal with a smaller reciprocating file was shown to favorably reduce the apical peak loads induced during canal shaping of extracted teeth.

Psychological Stress as a Determinant of Increased Maximum Voluntary Bite Force - A Clinical Observational Study.

Background Psychological stress is a known risk factor and modulator for several oral diseases. It is among the critical etiological factors of bruxism and several other disorders. The quantum of bite force is one of the prime determinants of wear resistance and the clinical performance of restorations. Thus, the present study aims to investigate the relationship between the maximum voluntary bite force (MVBF) and the amount of perceived stress experienced by an individual.  Materials and methods Patients (n=111) fulfilling the exclusion and inclusion criteria were divided into high, medium, and low-stress groups based on their stress scores deduced from the Perceived Stress Scale questionnaire (PSS). Bite force measurement was recorded in Newtons (N) for each subject using a portable customized bite recording FlexiForce sensor (B 201). The data were analyzed using Kruskal-Wallis and independent samples t-test. Results  Among the females, the bite force in the medium and high-stress groups was greater compared to the low-stress level group. On the other hand, there was no difference in bite force between any of the stress level groups among male participants.  Conclusion The results show that higher MVBF is associated with higher perceived stress scores in adult females. Practical Implications Psychological counseling can be included in the dental treatment plan of individuals with a high-stress score to counteract their stress-related higher occlusal forces, parafunctional jaw movements, and risky oral health behaviors, thereby potentially reducing the incidence of adverse outcomes such as temporomandibular joint dysfunction and restoration failure by careful choice of restorative materials.

Impact of cooling on shaping ability of thermally treated files in canal models with double curvature.

Background: This study compared the ability of thermally treated files in shaping simulated canals with double curvature. Fifty-six canals were enlarged to a final size of 25 with ProTaper Next (PTN) or ZenFlex (ZF). Materials: Half of the samples were shaped with cooled files (n = 14 each). The amount of removed resin was measured and canal deviation was determined at eight levels. Shaping time and maximum shaping torque values were also recorded. Data were statistically analyzed using analysis of variance and LSD, Kruskal-Wallis, and chi-square tests at a 0.05 significance level. Results: Compared to PTN and cooled PTN, ZF and cooled ZF required lesser time to shape the canals. The maximum torques were found comparable between the groups. All the groups generated negligible deviations at every canal level evaluated and maintained the canal geometry. Although not significant, the cooled PTN and ZF files exhibited lesser canal deviations than their counterparts. Conclusion: All groups demonstrated similar shaping ability whilst maintaining the original curvature of the canal in simulated canals with double curvature. However, ZF groups were able to shape the canals faster than PTN groups. There was a trend that cooled files made lesser canal deviations compared to their counterparts.

Retreatment of oval-shaped root canals filled with TotalFill bioceramic or AH plus sealer.

This study investigated retreatment of oval canals filled with gutta-percha and different sealers using WaveOne Gold (WOG). Single oval canals were prepared to size 30, 0.04 and obturated with gutta percha and AH Plus (AHP) or TotalFill bioceramic (TFBC) sealer. After 6-month incubation, the canals were retreated with WOG Primary (25, 0.07) under simulated body temperature, and the developed load and torque were simultaneously measured. The time and regaining the apical patency were checked. Micro-computed tomography scanning was performed to calculate the remaining obturating materials. An independent t-test and chi-square test were performed at a 95% confidence level. A shorter retreatment time was needed in TFBC than in AHP (P = 0.003). However, a higher maximum apical load was reported with AHP (P = 0.000). Meanwhile, comparable maximum coronal load and maximum torque values were observed. Apical patency was regained in all TFBC roots and only 75% of the AHP samples (P = 0.217). The remaining obturating materials were comparable in TFBC (13.02 ± 8.12%) and AHP (10.11 ± 8.46%) (P = 0.398). WOG was able to remove 89.89% and 86.98% of obturating materials in TFBC and AHP, respectively. The TFBC presented lower apical loads and faster retreatment compared to AHP.

Developments and Performance of Artificial Intelligence Models Designed for Application in Endodontics: A Systematic Review.

Technological advancements in health sciences have led to enormous developments in artificial intelligence (AI) models designed for application in health sectors. This article aimed at reporting on the application and performances of AI models that have been designed for application in endodontics. Renowned online databases, primarily PubMed, Scopus, Web of Science, Embase, and Cochrane and secondarily Google Scholar and the Saudi Digital Library, were accessed for articles relevant to the research question that were published from 1 January 2000 to 30 November 2022. In the last 5 years, there has been a significant increase in the number of articles reporting on AI models applied for endodontics. AI models have been developed for determining working length, vertical root fractures, root canal failures, root morphology, and thrust force and torque in canal preparation; detecting pulpal diseases; detecting and diagnosing periapical lesions; predicting postoperative pain, curative effect after treatment, and case difficulty; and segmenting pulp cavities. Most of the included studies (n = 21) were developed using convolutional neural networks. Among the included studies. datasets that were used were mostly cone-beam computed tomography images, followed by periapical radiographs and panoramic radiographs. Thirty-seven original research articles that fulfilled the eligibility criteria were critically assessed in accordance with QUADAS-2 guidelines, which revealed a low risk of bias in the patient selection domain in most of the studies (risk of bias: 90%; applicability: 70%). The certainty of the evidence was assessed using the GRADE approach. These models can be used as supplementary tools in clinical practice in order to expedite the clinical decision-making process and enhance the treatment modality and clinical operation.

Fiber Post Removal Using a Conservative Fully Guided Approach: A Dental Technique.

This report describes the usefulness of an endodontic template for the removal of a fiber post. A 40-year-old man presented with discomfort in the maxillary left canine. Clinical and radiographic examinations showed tooth #23 with a permanent core material retained with fiber post along with a persistent apical radiolucency. Among the various treatment modalities, nonsurgical root canal retreatment with fiber post removal using a conservative fully guided approach was proposed. After obtaining both the cone-beam computed tomographic images and the cast surface scan, their data were merged using implant planning software (ImplaStation for Windows x64 Bit Beta Version, ProDigiDent, Miami, Florida, USA) and superimposed. The drilling space was planned based on the location, diameter, and apical extent of the fiber post and was virtually overlapped and transferred clinically using a resin template to drill through the fiber post. With guides in position over the rubber dam, drilling was made with increments of 2 mm using a size 4 long-shank round bur (Thomas, Bourges, France) until it exposed the coronal gutta-percha. As soon as the canal was located, K3 rotary files (Sybron Endo, Orange, USA) were used along with chloroform to remove the old obturating materials. Then, additional shaping and cleaning were done with ProTaper Next rotary files (Dentsply Sirona, Ballaigues, Switzerland), sizes X2 and X3, and 5.25% NaOCl irrigation, respectively. The root canal was then dried with paper points and obturated with gutta-percha and AH Plus sealer (Dentsply Sirona, Ballaigues, Switzerland) using the continuous-wave compaction technique. Finally, the tooth was temporarily restored using the double seal technique with zinc oxide and zinc sulfate-based temporary material (Cavit W; 3M ESPE, St. Paul, MN, USA) and resin-modified glass ionomer material (Photac Fil; ESPE, Norristown, PA, USA) filling materials and referred for the final restoration.

Application and Performance of Artificial Intelligence Technology in Detection, Diagnosis and Prediction of Dental Caries (DC)-A Systematic Review.

Evolution in the fields of science and technology has led to the development of newer applications based on Artificial Intelligence (AI) technology that have been widely used in medical sciences. AI-technology has been employed in a wide range of applications related to the diagnosis of oral diseases that have demonstrated phenomenal precision and accuracy in their performance. The aim of this systematic review is to report on the diagnostic accuracy and performance of AI-based models designed for detection, diagnosis, and prediction of dental caries (DC). Eminent electronic databases (PubMed, Google scholar, Scopus, Web of science, Embase, Cochrane, Saudi Digital Library) were searched for relevant articles that were published from January 2000 until February 2022. A total of 34 articles that met the selection criteria were critically analyzed based on QUADAS-2 guidelines. The certainty of the evidence of the included studies was assessed using the GRADE approach. AI has been widely applied for prediction of DC, for detection and diagnosis of DC and for classification of DC. These models have demonstrated excellent performance and can be used in clinical practice for enhancing the diagnostic performance, treatment quality and patient outcome and can also be applied to identify patients with a higher risk of developing DC.

Assessment of Bioceramic Sealer Retreatability and Its Influence on Force and Torque Generation.

This study assesses the retreatability of TotalFill bioceramic (TFBC) and AH Plus (AHP) sealers and their impact on retreatment force and torque. Twenty-six premolar teeth with single oval canals were instrumented, obturated using the matched gutta-percha cone technique with one of the tested sealers, and then temporized. After a 6-month incubation at 37 °C and 100% humidity, the canals were retreated with the XP Shaper system. During retreatment, the generated force and torque were measured. Micro-CT scanning was run before and after the retreatment procedure to analyze the remaining obturating materials in the canals. The apically directed maximum force in AHP was higher than that in TFBC. The coronally directed maximum force and the maximum torque were comparable between the groups. A higher amount of remaining obturating materials was found in the AHP compared to that in the TFBC. Based on these findings, endodontic sealer had an influence on retreatability, and the TFBC showed less remaining obturating materials and lower retreatment forces in the apical direction compared to the AHP in extracted teeth with oval canals.

Scientometric evaluation of endodontic publications by Gulf Cooperation Council region in 21st century.

OBJECTIVES: The appraisal of research productivity is one of the key indicators to evaluate any area of knowledge. The current study aimed to analyze the Scopus-indexed publications on endodontics produced by Gulf Cooperation Council (GCC) region from 2000 to 2020. METHODOLOGY: The dataset was extracted in May 2021 from Elsevier's Scopus database. Two keywords ("endodontic" and "endodontics") were entered into the basic search with the Boolean operator of OR for a period of 20 years from 2000 to 2020. RESULTS: Overall, the GCC region contributed 2.82% of the global endodontic research. This share has shown a remarkable increase between 2001 and 2020 from 0.82% to 7.20%. About 60% of documents' volumes were produced during the 2016-2020 period. Around 80% of research was produced by Saudi Arabia, while research articles produced by Kuwait gained the highest citation impact. Out of the ten productive institutions, nine belonged to Saudi Arabia and one was from Kuwait. The majority of research collaboration was conducted with the United States, but research articles produced in collaboration with Japan yielded the highest citation impact. CONCLUSION: The study highlighted various scientometric attributes of endodontic publications produced by GCC affiliated researchers. The ongoing growth of endodontic literature by GCC countries along with the increasing international collaboration is considered aspiring.

Evaluation of YouTube videos for patients' education on periradicular surgery.

The aim of this study was to evaluate the content of periradicular surgery-related YouTube videos available for patients' education. YouTube search was made for videos related to periradicular surgery using specific terms. After exclusions, 42 videos were selected, viewed and assessed by two independent observers. The videos were assessed in terms of duration, days since upload, country of upload, number of views, likes and dislikes, authorship source, viewing rate and interaction index. To grade the content of videos about periradicular surgery, a usefulness score was created with 10 elements based mainly on the American Association of Endodontists guidelines. Each element was given a score of 0 or 1. SPSS software (SPSS Inc, Chicago, IL, USA) was used to analyze data at a 95% confidence level. An inter-evaluator reliability analysis for the scoring system was performed using the Kappa statistic. The videos received an average of 35103.9 views (range: 9-652378) with an average duration of 338.71 seconds (range: 42-2081), respectively. Most videos were provided by individuals (57%). Half of the videos were posted by authors from the United States. The inter-evaluator reliability for usefulness scoring was 94.5%. No video covered the 10 scoring elements completely, presenting very low usefulness scores (mean: 3.2; range: 1-7). The most discussed elements were supporting media (100%) and steps of the procedure (90.5%) followed by indications and contraindications (45.2%) and symptoms (31%). None of the included videos discussed the procedure's cost or prognosis. In terms of usefulness score, no significant difference was detected between different sources of upload (chi-square test, P > 0.05). Information on periradicular surgery in YouTube videos is not comprehensive and patients should not rely on YouTube as the only source of information. Dental professionals should enrich the content of YouTube with good quality videos by providing full and evidence-based information that will positively affect patients' attitudes and satisfaction.

Evidence for reduced torsional resistance of rotary files under curved position.

OBJECTIVES: The aim of this in vitro study was to investigate the torsional fatigue resistance of different rotary files in straight and curved positions at a simulated intracanal temperature. METHODS: Forty-eight size #25 files from ProTaper Universal (PTU), ProTaper Next (PTN) and ProTaper Gold (PTG) were tested for torsional resistance in both straight and curved (90 degrees) positions (n = 8 each). The experiment was conducted at a simulated intracanal temperature of 35 ± 1 °C. The torque gauge was reset before every use, and uniform torsional stress was applied by rotating the file clockwise at a speed of 40 rpm until fracture. Torque failure values were recorded, and fractured surfaces were tested using a scanning electron microscopy (SEM). Statistical analysis of the data was completed using one-way ANOVA and post-hoc test (LSD) in order to compare between the tested systems in each file position. Student's t-test was also performed to compare between the two positions in each rotary system, and significance level was set at 5%. RESULTS: In the straight position, torsional resistance of PTN was significantly lower than that of PTU and PTG (p < 0.001), while the PTU and PTG had comparable results (p > 0.05). In the curved position, torsional resistance was found to be comparable among all systems (p > 0.05). Within each system, the curved position resulted in a significantly lower torsional resistance when compared to the straight position (p < 0.001). SEM examination revealed similar torsional failure behavior for all files tested under both positions. CONCLUSIONS: Our study identified that placing files in a curved position was associated with a significant decrease in torsional resistance of all systems, and this necessitates reconsidering the torque settings proposed by the manufacturers. Whether these effects can be translated into in vivo studies remains to be investigated, and thus future studies are essential to provide confirming evidence.

Influence of additional apical enlargement on microcrack formation in root dentine: a micro-computed tomography investigation.

OBJECTIVES: To assess the effect of additional apical enlargement using nickel titanium (NiTi) instruments on the incidence of microcracks using micro-computed tomographic analysis. MATERIALS AND METHODS: Fifty-one premolars with single canals were enlarged to ProTaper Gold (PTG) F2 (25/08) (Dentsply Sirona), ProFile Vortex Blue (VB) 25/06 (Dentsply Tulsa), or WaveOne Gold (WOG) primary (25/07) (Dentsply Sirona) NiTi rotary instruments (n = 17 each). Afterward, additional apical enlargement was performed in each group with its corresponding larger instrument (F3 (30/09), VB 30/06, or WOG Medium (35/06) instruments, respectively). All teeth were imaged with micro-computed tomography before canal enlargement and after initial and additional apical enlargements to detect new microcracks at the apical 5 mm. An Aligned Rank Transform ANOVA was conducted to examine the effects of file type and canal enlargement on the number of new microcracks resulting from enlargement. A Kruskal-Wallis test was run to compare the file types at each canal enlargement stage. RESULTS: A significant main effect (P = 0.026) of canal enlargement on the number of new microcracks was found; the number of apical microcracks found after additional enlargement was significantly greater than baseline (P = 0.021); no significant difference was found between baseline and initial enlargement (P = 0.506) and between initial enlargement and additional enlargement (P = 0.252). The Kruskal-Wallis tests found no difference between file types at baseline (P = 0.348), after initial enlargement (P = 0.369) or additional enlargement (P = 0.133). CONCLUSIONS: Regardless of the instrumentation system used, additional apical enlargement led to the formation of high number of new microcracks. CLINICAL SIGNIFICANCE: The results indicated that additional enlargement induced significant number of apical microcracks.

Influence of Neuroticism on the Prognosis of Nanoceramic and Microhybrid Composite Restoration: A Comparative 1-year Clinical Study.

AIM: This study aimed to compare the clinical performance of nanoceramic and microhybrid-based composite restorations in adult patients with different personality traits. MATERIALS AND METHODS: Patients in accordance with the inclusion and exclusion criteria were asked to complete the BFI (Big Five Inventory) questionnaire. Of a total of 323 patients, 124 (67 males and 57 females) patients were categorized into agreeableness and neuroticism traits and were included in the study. The patients were randomly divided into two subgroups: SG I A (n = 31) and II A (n = 31) for microhybrid composite (Spectrum TPH 3, Dentsply/DeTrey, Konstanz, Germany), SG I B (n = 31) and II B (n = 32) for nanoceramic composite restorations (Ceram X mono, Dentsply/DeTrey, Germany). At baseline, 6 and 12 months, the restorations were evaluated using the Modified USPHS (United States Public Health Service) evaluation criteria. The Pearson chi-square and the Fisher's exact test were used to assess the difference between the personality traits and restorative material groups where a probability value of P < 0.05 was considered to be statistically significant. RESULT: Most of the restorations scored alfa (A), whereas very few scored bravo (B) in all the subgroups. However, there were no charlie (C) or delta (D) scores. Overall, Spectrum TPH and Ceram x mono displayed superior performances in retention and postoperative sensitivity than all the other clinical parameters. Furthermore, Ceram x mono restorations showed more surface roughness than Spectrum TPH. No statistical differences in the restoration performance were found between both personalities and restorative material types. CONCLUSION: Although neuroticism has an effect on various health outcomes, its impact on the clinical performance of composite restorations during the follow-up period was not observed. In addition, there was no difference between the performance of nanohybrid and microhybrid composite.

Analysis of Force and Torque with XP Shaper and OneCurve Systems During Shaping of Narrow Canals.

Objective: The purpose of this laboratory-based study was to compare the shaping forces and torques developed by the XP Shaper (FKG Dentaire SA, La Chaux-de-fonds, Switzerland) and OneCurve (Micro-Mega, Besancon, France) systems during shaping of narrow canals. Methods: Mandibular premolars with a single canal were divided equally into two groups; XP Shaper and OneCurve (n=16 each). In both groups, the canals were shaped with XP Shaper file (30/01) or OneCurve file (25/O6) that was inserted three times until it reached the canal length. The tooth was surrounded by water under controlled simulated intracanal temperature throughout the experiment. The inward and outward peak forces and the peak torques were recorded and analyzed statistically using the Mann-Whitney test. The shaping times were analyzed using Student's t-test. The significance level was set at 5%. Results: In both groups, the developed forces in both directions and the torques increased with the successive insertions of the file. In the two groups, the inward peak forces ranged from 0.33 to 3.12 N, while the outward peak forces ranged from 0.09 to 1.96 N. In the three insertions, the XP Shaper showed significantly lower peak forces in both directions. The peak torque developed in both groups ranged from 0.12 to 1.52 N.cm. XP Shaper had significantly lower torque values in all the insertions than OneCurve. The XP Shaper system was able to completely shape the canals in 33.4 seconds while the OneCurve system was able to completely shape the canals in 32.8 seconds. Conclusion: The XP Shaper system showed favorably lower force and torque values during canal shaping compared with the OneCurve system.

A Rare Case of Single-Rooted Mandibular Second Molar with Single Canal.

The root canal anatomy of mandibular second molar teeth is known to be highly variable. Whilst the most frequently seen configuration is two mesial canals and one distal canal, other variations such as four canals, two canals, and C-shaped canal system do also exist. This case report describes the diagnosis and management of unusual root canal configuration of a mandibular second molar, with one canal in a single conical root, using the contemporary advancements in endodontics. Following clinical and radiographic examinations of the case, a diagnosis of symptomatic irreversible pulpitis with symptomatic apical periodontitis of tooth #47 was established, and root canal treatment followed by composite buildup and crown were planned. Clinicians should be aware of the different anatomic variants each tooth may exhibit. Furthermore, clinicians need to possess the proper knowledge and skills that allow them to utilize the diagnostic and therapeutic tools available at their disposal in order to optimize the quality of care provided to their patients.

Shaping Ability of XP Endo Shaper File in Curved Root Canal Models.

The aim of this study was to assess the shaping ability of the XP Shaper (XPS) file in severely curved canal models under simulated body temperature and compare it with that of the WaveOne Gold (WOG) file. Ninety-six simulated root canals were equally distributed into XPS and WOG systems to be shaped by eight files each. Files were assessed under a stereomicroscope prior to canal shaping to detect deformation if any. The canals were shaped at 35 ± 1°C using the X-Smart Plus motor. Images of the canals were obtained before and after instrumentation using a stereomicroscope to measure the amount of removed resin from both the inner and outer curvature sides at apex (0 mm) and 3 mm and 6 mm from the apex. The shaping time was calculated. The data were statistically analyzed by the independent t-test at 5% significance level. The XPS and WOG systems shaped the canals in 37.0 ± 9.5 and 62.6 ± 11.3 seconds (P < 0.05), respectively. At the apex level, the amount of resin removal in both sides did not show a significant difference between the tested groups (P > 0.05). At 3 mm and 6 mm levels, the WOG removed more resin than XPS at both sides (P < 0.05). In XPS, deformation was observed in four files: one file after the first use, one file after the fourth use, and two files after the sixth use. In WOG, two files were deformed: one file after the fifth use and one file after the sixth use. One XPS file was fractured after the sixth use. In short, XPS and WOG files can be used in shaping severely curved canals as they showed the ability to maintain the original shape with minimal transportation. Both file systems showed signs of deformation after use with a lower number of deformed files observed in WOG throughout the experiment.

Psychological Impact of the COVID-19 Pandemic on Dental Interns in Riyadh, Saudi Arabia: A Cross-sectional Survey.

BACKGROUND: Dental profession is labeled as a high-risk profession, due to which dental care professionals are under tremendous pressure during the outbreak of COVID-19 pandemic. The aim of this study was to assess the psychological impact of the COVID-19 pandemic on dental interns in Riyadh, Saudi Arabia. MATERIALS AND METHODS: A cross-sectional study was conducted among dental interns from different universities in Riyadh, Saudi Arabia. The data were collected using a validated Depression, Anxiety and Stress Scale-21 Items (DASS-21) questionnaire. Descriptive statistics were presented using frequencies (n) and percentages (%). Chi-square and Fisher exact tests were used to assess the association between sociodemographic data (age, gender, nationality, marital status, and history of physical and mental illness) and levels of depression, anxiety, and stress. A p < 0.05 was considered as statistically significant. RESULTS: A total of 160 dental interns were invited to participate in this survey; out of which 110 participants responded yielding a response rate of 78%. The mean age of the study participants was 25.1 years. About 65% of the participants were female. Only 14.5% of the subjects reported having a past history of physical or mental illness. Depression, anxiety, and stress were identified in 11.9%, 7.3%, and 0.9% of the dental interns, respectively. Demographic characteristics did not appear to influence depression, anxiety, or stress levels (p > 0.05). CONCLUSION: The outbreak of COVID-19 pandemic has affected the mental health of dental interns. The presence of depression, anxiety, and stress among dental interns highlights the need for special intervention and support programs to promote mental health and well-being among dental interns. HOW TO CITE THIS ARTICLE: Khanagar SB, Alfadley A. Psychological Impact of the COVID-19 Pandemic on Dental Interns in Riyadh, Saudi Arabia: A Cross-sectional Survey. Int J Clin Pediatr Dent 2020;13(5):508-512.

Cyclic Fatigue and Torsional Failure of EdgeTaper Platinum Endodontic Files at Simulated Body Temperature.

INTRODUCTION: The aim of this in vitro study was to compare the cyclic fatigue resistance and torsional resistance of EdgeTaper Platinum (ETP) with those of ProTaper Gold (PTG) at simulated body temperature. METHODS: ETP and PTG files with #25 tip size were selected. Cyclic fatigue tests were performed in a stainless steel artificial canal until file fracture occurred. The time to fracture was recorded. For the torsional resistance testing, the apical 5 mm of the file was firmly secured with acrylic resin, and the assembly was fixed over torque gauge device. A uniform torsional stress was applied with continuous rotation motion until fracture occurred. The torque at failure was recorded. Both experiments were conducted at 35 ± 1°C. Fractured surfaces were tested via scanning electron microscopy. Statistical analysis was performed using independent Student t test at 5% significance level. RESULTS: The ETP had superior cyclic fatigue resistance than PTG (P < .01). However, it exhibited lower torsional resistance (P < .05). The ETP and PTG showed typical features of cyclic and torsional fatigue behavior under scanning electron microscopy. CONCLUSIONS: The ETP exhibited superior resistance to cyclic fatigue but failed to show any improvement in the torsional resistance compared with PTG.

Detecting the Second Mesiobuccal Canal in Maxillary Molars in a Saudi Arabian Population: A Micro-CT Study.

The aim of this study was to determine MB2 canal detectability in maxillary first and second molars obtained from a Saudi population using micro-CT. Maxillary first (n = 35) and second (n = 30) molars were scanned with micro-CT technology. The number of canals was recorded, and in case of having more than one canal, the level of extracanal detection was analyzed. The presence of extracanal was categorized based on the level they were first detected. Among the maxillary first molars, 28 (80%) and six (17%) teeth had two and three MB canals, respectively. Among the maxillary second molars, 24 (80%) and four (13%) teeth had two and three MB canals, respectively. The MB2 canal was detected at the chamber floor in 70% and 61% of the maxillary first and second molars, respectively. At 1 mm depth, the MB2 canal was found in 15% and 18% of the maxillary first and second molars, respectively. At 2 mm depth, the MB2 canal was found in 3% and 18% of the maxillary first and second molars, respectively. The remaining teeth had the MB2 canal at levels deeper than 2 mm. The MB2 canal was detected in 97% and 93%% of maxillary first and second molars, respectively. Among them, the MB2 canal could be immediately detected in 70% and 61% of the maxillary first and second molars, respectively, once the pulp chamber is exposed. However, the rest of the MB2 were observed at deeper levels in the root and this requires troughing preparation in the chamber floor.