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Abstract Objective This study aimed to evaluate a new deep-learning model for diagnosing avascular necrosis of the femoral head (AVNFH) by analyzing pelvic anteroposterior digital radiography. Methods The study sample included 1167 hips. The radiographs were independently classified into 6 stages by a radiologist using their simultaneous MRIs. After that, the radiographs were given to train and test the deep learning models of the project including SVM and ANFIS layer using the Python programming language and TensorFlow library. In the last step, the test set of hip radiographs was provided to two independent radiologists with different work experiences to compare their diagnosis performance to the deep learning models’ performance using the F1 score and Mcnemar test analysis. Results The performance of SVM for AVNFH detection (AUC = 82.88%) was slightly higher than less experienced radiologists (79.68%) and slightly lower than experienced radiologists (88.4%) without reaching significance (p-value > 0.05). Evaluation of the performance of SVM for pre-collapse AVNFH detection with an AUC of 73.58% showed significantly higher performance than less experienced radiologists (AUC = 60.70%, p-value

Abstract The traditional methods in early caries detection had many limitations. So, this study aimed to evaluate the clinical performance of alternating current impedance spectroscopy ACIST in comparison with digital radiograph and ICDAS-II in detection of occlusal carious lesions. Occlusal surfaces of molar and premolar teeth from 40 adult participants were examined by two observers using three diagnostic methods: (1) international caries detection and assessment system (ICDAS-II) (2) digital radiograph (DR) and (3) Cariescan Pro device (ACIST). Agreement analysis and the difference in sensitivities and specificities were evaluated. The results showed an excellent agreement in the different groups. The difference from the visual tactile against ACIST scoring for enamel caries detection, was statistically significant (p = 0.012) and the agreement was moderate (k = 0.509). For dentinal caries the difference was not statistically significant (p > 0.05) and the agreement was similarly moderate (k

Background: Dental radiography is an integral part of intraoral evaluation. Children are often uncomfortable during the placement of film or sensor due to the impingement of the soft tissues. Thus, the perception of pain with three intraoral radiographic methods in children was evaluated using three subjective pain rating scales. Aim: To evaluate the discomfort with three different techniques, that is, intraoral periapical (IOPA) radiograph, charge-coupled device (CCD), and photostimulable phosphor (PSP) luminescence (PSPL), using the Wong–Baker Faces Pain Rating Scale (WBFPRS), numerical rating scale, and visual analog scale (VAS). Materials and Methods: A sample of 35 children aged 6–12 years were divided into two groups: group 1 (6–8 years) and group 2 (9–12 years). For each child, simulations of the three radiological methods (IOPA, CCD, and PSPL) were performed. The meaning of each facial expression on the WBFPRS, VAS, and the numbers on the numerical rating scale was explained to each child before the procedure. Statistical Analysis Used: A one-way analysis of variance (ANOVA) test and paired-samples t-test are used. Results: The results revealed that the CCD sensors elicited higher pain scores than those obtained with IOPA and PSPL, whereas the IOPA film showed the least pain score. Higher score values were obtained in group 1 than in group 2, indicating that children aged 6–8 years felt higher discomfort than the 9- to 12-year age group for the same procedure. This difference was statistically significant (P < 0.001). Conclusion: It was concluded that conventional IOPA films were tolerated better by children when compared to PSP plates and CCD sensors.

ObjectiveTo investigate the entrance surface dose （ESD） of digital radiography （DR）adult examinees in a grade A tertiary hospital in Shanghai， to analyze the dose level of the DR adult examinees， and to provide data for the development of DR typical dose reference.MethodsA DR equipment in the hospital was selected and the irradiation parameters and dose were determined in two randomly selected age groups （15‒39 years and 40‒69 years） of DR adult examinees. The examinations included chest PA， chest LAT， abdominal AP， pelvic AP， lumbar AP， lumbar LAT， thoracic AP， and thoracic LAT. The number of examinees in each exposure position was 20. ESD and effective dose were calculated for each age group and each position.ResultsA total of 320 examinees were investigated. The 75th percentiles of ESD in different exposure positions were as follows： chest PA 0.19 mGy；chest LAT 0.96 mGy；abdominal AP 3.63 mGy；pelvic AP 3.16 mGy；lumbar AP 9.27 mGy；lumbar LAT 18.29 mGy；thoracic AP 6.85 mGy；and thoracic LAT 13.40 mGy.ConclusionsThe differences between the estimated ESD and effective dose were large in different exposure positions、in the same exposure positions、and in the same positions with different exposure types， and there were statistically significant differences in ESD of examinees with different exposure positions. The estimated typical values of different exposure positions were apparently lower than the diagnostic reference level.

Abstract Objective Radiographs are an integral part of detecting proximal caries. The aim of this study was to evaluate the effect of contrast, brightness, noise, sharpness, and γ adjustment of digital intraoral radiographs on the diagnosis of proximal caries. Materials and methods In this in vitro study, 40 extracted teeth including 20 premolars and 20 molars with enamel lesions (white spot or dentin discoloration seen through the enamel) were mounted together in groups of eight inside the skull. Bitewing radiographic images of each dental group were obtained by a photostimulable phosphor plate sensor with exposure conditions of 8 mA, 70 kV, and 0.2 s. The images were reconstructed by the built‐in software and examined by two oral and maxillofacial radiologists in various settings of contrast, brightness, sharpness, noise, and γ. The teeth were then cut mesiodistally and the presence or absence of caries was confirmed by an oral and maxillofacial pathologist using a stereomicroscope. The data were then analyzed using the κ agreement coefficient, sensitivity, specificity, and accuracy (α = .05). Results Adjustment of brightness and contrast led to higher diagnostic performance with an accuracy of 82.5% and 83.8 (for observers 1 and 2, respectively) and 82.5% (for both observers), respectively. Noise adjustment was the least helpful approach for diagnosis of proximal dental caries among other adjustments, with an accuracy of 78.8% and 77.5% for observers 1 and 2, respectively. Conclusion Brightness and contrast setting was more efficient in improving the diagnostic potential of bitewing radiographs compared to other adjustments.

As part of a detailed investigation project focused on the painting materials and technical features used in Wallachia during the 17th and 18th century, the imperial icon “Mother of God with Child” from the Orthodox Church of the “Annunciation” in Râmnicu Vâlcea, Romania, was investigated before the restoration intervention. A minimally invasive multi-analytical approach consisting of high-resolution digital radiography, hyperspectral imaging, UV fluorescence imaging, portable X-ray fluorescence, and Fourier transform infrared spectroscopy was used. The results emphasized several key features, such as: the structure of the wooden panel, the nature of pigments and of the painting technique frequently used at that time, and various defects of the pictorial layer including traces of previous restoration works, most probably made at the end of the 18th century.

Amaç: Bu çalışmanın amacı, ışıkla uyarılabilen fosfor (Photostimulable Storage Phosphor, PSP) plakalarının ışınlama-tarama süreçleri arasındaki farklı tarama gecikmeleri (bekletme süresi) ve saklama koşullarının görüntülerindeki Ortalama Gri Değer (OGD) değişimine etkisini değerlendirmekti. Gereç ve Yöntem: Saklama koşuluna göre oluşturulan dört grupta [Tek Kılıf Aydınlık (TKA), Tek Kılıf Karanlık (TKK), Tek Kılıf Karton Aydınlık (TKKA), Tek Kılıf Karton Karanlık (TKKK)] farklı bekletme sürelerinde toplam 40 görüntü elde edildi. ImageJ (National Institutes of Health, Bethesda, MD) programı ile görüntülerin OGD’leri ölçüldü. Saklama koşullarını karşılaştırmak için tek yönlü, bekletme sürelerini karşılaştırmak için iki yönlü tekrarlı ölçümlü ANOVA testleri kullanıldı. Her bir gruptaki bekletme süreleri ile 0 dk. (altın standart) OGD’lerin karşılaştırılması için eşleştirilmiş örneklemler t-testi uygulandı. p0.05). Altın standart dışındaki diğer bekletme süreleri karşılaştırıldığında, 24 saat bekletme süresi ile diğer bekletme süreleri OGD’leri arasında istatistiksel olarak anlamlı fark vardı (p

Abstract Purpose This study aimed to assess the diagnostic accuracy of cone-beam computed tomography (CBCT) and digital intraoral radiography for the detection of proximal caries adjacent to amalgam, e.max porcelain, and metal-ceramic restorations (MCRs). Materials and methods Parallel intraoral radiographs were obtained from 40 posterior teeth using PSP sensors. To obtain CBCT scans, the teeth were first radiographed alone, and were then positioned next to a tooth with an amalgam restoration, MCR, and e.max porcelain crown, and radiographed again. Two blinded observers scored radiographs using a four-point scale (0: absence of proximal caries, 1: enamel caries, 2: carious lesion extending to the outer half of dentin, 3: carious lesion extending to the inner half of dentin). Tooth sections were made, and the grade of caries was determined under a light microscope at x12 magnification. The sensitivity, specificity, and accuracy of CBCT and intraoral radiographs were then calculated. Results Artifact-free CBCT scans and intraoral radiographs had the highest diagnostic accuracy (0.826 and 0.657, respectively) while CBCT images of the teeth next to the amalgam restorations (0.526) had the lowest accuracy. The diagnostic accuracy of CBCT images of the teeth next to the porcelain crowns and MCRs was 0.613 and 0.601, respectively. Conclusion Artifact-free CBCT images had higher diagnostic accuracy than intraoral radiography for the detection of all grades of proximal caries. The diagnostic accuracy of CBCT images of teeth adjacent to amalgam, porcelain, and MCRs was lower compared to intraoral radiographs and artifact-free CBCT images.

Introduction: Digital radiography seems necessary for overcoming educational problems and archiving radiographs taken from patients; nonetheless, the views of students and professors about this issue have been less studied. Therefore, the present study aimed to investigate the satisfaction of professors and students with the use of conventional and digital radiography in the Endodontics Department of Mashhad Dental School.Materials and Methods: This study was conducted on the professors of the Department of Root Therapy and 155 Dental Students in Mashhad. The research tool consisted of two researcher-made questionnaires. The first questionnaire was about the quality of the root therapy that was completed by the professors. The second questionnaire was about students' satisfaction with the use of digital and conventional radiography in the endodontics section. The information was recorded, and the data were then compared using Chi-square and Fisher tests.Results: The findings of this study demonstrated that from professors' point of view, digital imaging in dentistry had better quality, shorter time, and less error, and professors' satisfaction was significantly higher. Moreover, students had a more positive opinion of digital imaging in terms of quality, less time, less error, and less student congestion. Finally, students were more satisfied with digital imaging (P=0.05).Conclusion: As evidenced by the obtained results, it can be concluded that digital radiography improved the education and satisfaction of both groups of students and professors.

Abstract Background External root resorption (ERR) has a multifactorial etiology and is difficult to diagnose, which means that is continues to be of research interest. This work mainly aims to determine whether external root resorption can be differentially detected in root-filled versus non-endodontically treated teeth using digital periapical radiography (DPR) and cone-beam computed tomography (CBCT). Methods The Checklist for Reporting In-vitro Studies (CRIS) guidelines were followed throughout this study. This experiment highlights the preparation and generation of standardized synthetic teeth measured on three-dimensional records converted into Digital Imaging and Communication on Medicine (DICOM) file format. Twelve replicate maxillary incisors were randomized into two groups: (G1) six non-endodontically treated, and (G2) six endodontically treated teeth. In both groups, actual tooth lengths of all specimens were measured and compared with measurements obtained using DPR and CBCT. Simulated ERR lesions [0.12, 0.18, 0.20 mm × 0.5 mm depth in the mesial, distal and palatal apical regions] were created progressively, radiographic images were recorded, and 24 DPRs and 96 CBCTs were obtained in total. Eight blinded, previously calibrated researchers made a total of 1920 measurements (using Horos Software). Data were analyzed using the Shapiro–Wilk, ANOVA, Kruskal–Wallis and Wilcoxon rank post-hoc tests [Bonferroni correction in multiple comparison tests (p

Radiographic methods provide useful information about bone tissue changes, and radiographs have the advantage that they can be stored and reevaluated at any time. However, radiographic evaluations are subject to several sources of error. The purpose of this study was to analyze the maxillary bones by computer tomographic analysis, assessing the value of their density as a predictive element in the success of oral rehabilitation by classical or modern methods. In this study, we selected 35 patients for dental CT scans made with a Somatom Emotion device, Siemens in order to apply dental implants and removable prostheses. 20 women and 15 men aged between 60-80 years participated in the study . For comparison, 6 dental CT scans from the group of patients under the age of 65 were analyzed. The measurements were made on approximately symmetrical right-left areas. A line parallel to the long axis of the horizontal branch of the mandible, tangential to the lower edge, was drawn. The correlative aspects established between the patient’s sex, bone density and the dimensions of the edentulous ridges underline a prevalence, in percentage of 55%, of medium ridges in the frontal area, associated with the female sex and a D3 bone density, while medium ridges both frontally and laterally associated with D3 density and association with the male sex. The value of the CT examination in evaluating the quality of edentulous ridges and some foreign bodies and sinus inflammatory processes with the evaluation of the proximity of important anatomical structures as landmarks in implantology is evident.

Abstract Introduction Collimation of the primary beam is an important factor in radiography to reduce dose and improve image quality. The introduction of larger detector plates in direct digital radiography (DR) allows the exposed area to be calculated by removing cropping applied to the image. The aim of this study was to assess whether the exposed area was larger than a reference standard across five different projections on different body types, with the reference size being the corresponding cassette size used in traditional film/screen or computed radiography (CR). Method A retrospective clinical audit of five common musculoskeletal radiographic projections (AP knee, AP shoulder, horizontal beam lateral hip, lateral cervical spine and lateral facial bones), of 359 patients was undertaken. The electronic cropping was removed from projections, and the superior–inferior, antero‐posterior and medio‐lateral collimation size was measured, depending on the projection. The two measurements were multiplied to give an exposed field of view area. The three measurements were compared with a reference standard, being the size of the corresponding cassette size used in the department on film/screen or computed radiography. Results From the five projections, 1071 measurements were analysed. 416 (38.8%) of these measurements were less than or equal to the agreed reference standard. 655 (61.2%) were greater than the agreed reference standard. Conclusion The study demonstrates that the majority (61.2%) of the measurements taken were above the reference standard. This results in an increase in radiation dose to patients and detrimental impacts on image quality.

In radiography, an antiscatter grid is a well-known device for eliminating unexpected x-ray scatter. We investigate a new stationary grid artifact suppression method based on a nonsubsampled contourlet transform (NSCT) incorporated with Gaussian band-pass filtering. The proposed method has an advantage that extracts the Moiré components while minimizing the loss of image information and apply the prior information of Moiré component positions in multi-decomposition sub-band images. We implemented the proposed algorithm and performed a simulation and an experiment to demonstrate its viability. We did this experiment using an x-ray tube (M-113T, Varian, focal spot size: 0.1 mm), a flat-panel detector (ROSE-M Sensor, Aspenstate, pixel dimension: 3032 × 3800 pixels, pixel size: 0.076 mm), and carbon graphite-interspaced grids (JPI Healthcare, 18 cm × 24 cm, line density: 103 LP/inch and 150 LP/inch, ratio: 5:1, focal distance: 65 cm). Our results indicate that the proposed method successfully suppressed grid artifacts by reducing them without either reducing the spatial resolution or causing negative side effects. Consequently, we anticipate that the proposed method can improve image acquisition in a stationary grid x-ray system as well as in extended x-ray imaging.

Background/Aim: Dentistry has made major progress due to modern advancements in radiology. It would be interesting to examine the correlation of dental science with the labor market, as well as to assess dentists' adaption to nowadays' scientific and financial circumstances. This research aims to investigate the opinions of dentists in Thessaloniki, Greece, with regard to choosing the appropriate radiographic examinations in various clinical cases, and to canvass their knowledge of radiation protection. Material and Methods: Our sample was comprised of 7% of private dentists working in the urban complex within the borders of Thessaloniki, Greece. Self-referential multiple choice questionnaires were distributed via email. For the statistical analysis, GoogleForms was utilized, and objectivity was guaranteed by ensuring participants' anonymity. Results: The replies underwent statistical analysis with the use of Google Forms, and through this process charts have been produced. Orthopantomograph is the most usual radiographic examination for new patients and for the evaluation of complications. Dentists' age and gender seem to affect their radiographic choices in everyday clinical practice. Regarding intraoral radiography, the paralleling technique is more usually applied. Moreover, the findings suggest the need for dentists' constant education on radiation protection. Last but not least, most participants choose digital intraoral radiography. Conclusions: Dentists tend to seek assistance from radiological laboratories for special radiographies, such as cone-beam computed tomography, as well as in cases of diagnostic dilemma. They also recognize digitalization's contribution to keeping health records. Consequently, clinicians' additional education, financial motives for the upgrade of radiological equipment and records' digitalization are fundamental prerequisites for modern dentistry.

Introduction: Postmenopausal women are more at risk of osteoporosis than men of the same age. Osteoporosis is often undetected due to lack of symptoms. The aim of the study was to explore the potential of gray value (GV) in clinical panoramic radiographs as a screening method for osteoporosis. Cross-sectional comparative study using secondary data. GV of mandible in panoramic radiographs between male and female of several age groups were compared. X-ray parameters were considered. Materials and Methods: A total of 294 panoramic radiographs were obtained from regular clinical activity regardless of mA (3.3–8 mA), and divided into sexes and ages 31 to 45, 46 to 60, and 61 to 75 years old. A subset of 60 panoramic radiographs obtained by a narrow range of mA (5.7–6.4 mA) were randomly selected and then divided into sexes and ages 32 to 53 and 54 to 75 years old. Average GV was recorded. Average GV between age groups (divided by sexes) was evaluated by one-way analysis of variance (ANOVA) for groups with unrestricted mA, and unpaired t-test for restricted mA. Results: Average GV without mA restriction were not significantly different between age groups in men (P = 0.883) and women (P = 0.617). If mA is restricted, average GV was significantly different between age groups in women (P = 0.007) but were not significantly different between age groups in men (P = 0.386). Conclusion: GV obtained from panoramic radiographs may have potential in detecting osteoporosis if x-ray parameters are kept in narrow range. It would not have the same screening potential if the range of x-ray parameters are too wide.

This study aimed to compare the accuracy of three types of apex locators versus digital radiography for working length (WL) determination. This experimental study was conducted on 58 extracted maxillary premolars. The teeth were decoronated, the access cavity was prepared, and WL was determined using a #15 K-file to serve as reference. The WL was then measured by Woodpex V, Woodpex III, and Root ZX apex locators in the presence of 0.9% saline, and also on a photostimulable phosphor plate (PSP) digital radiograph taken by the parallel technique. The values were compared with the actual WL using the paired t-test (alpha = 0.05). Digital radiography, Root ZX, Woodpex V, and Woodpex III determined the WL within ±0.5 mm from the actual value in 84.48%, 100%, 89.66%, and 87.93% of the cases, respectively. Woodpex V (p = 0.039), Woodpex III (p = 0.001), and Root ZX (p = 0.001) significantly over-estimated the WL. The WL measured on digital radiographs was not significantly different from the actual WL (p = 0.213). The position of the apical foramen (central/lateral) had no significant effect on the accuracy of WL determination by different techniques (p >0.05). Within the limitations of this in vitro study, all the tested modalities showed acceptable accuracy for WL determination in maxillary premolars.

Background: The aim of this study was to compare the accuracy of apex locator, digital periapical radiography, and cone-beam computed tomography (CBCT) for determining the root canal working length (WL) in teeth with external root resorption (ERR). Materials and Methods: In this in vitro study, the sample consisted of 54 extracted permanent single-rooted human teeth. ERRs were performed at the 3 mm apical root using 65% of nitric acid for 24 h. After determining the actual WL by K-file #10 (gold standard) with the visualization method, the teeth were mounted in alginate and the WL of each tooth was determined using the electronic apex locator (EAL) equipped with a K-file #15. The teeth were mounted with wax in the teeth sockets of a dry human mandible, and the images were obtained by digital phosphor plate receptors and CBCT scans. The mean registered WL of each method was statistically compared with the gold standard WL using one-way ANOVA with P < 0.001. Results: The mean ± standard deviation (SD) of actual WL was 16.00 ± 2.24. The mean ± SD of WLs determined by CBCT, EAL, and digital radiography were 15.38 ± 2.19, 15.52 ± 2.32, and 16.83 ± 2.20, respectively. This study showed that the mean measured WL with ERR in all methods was significantly different from the actual WL (P < 0.001). Conclusion: This study showed that there was a significant difference between the actual mean WL and the EAL, digital periapical radiography, and CBCT mean WL. Thus, the combination of EAL and CBCT could be a reliable method for determining WL in the presence of ERR.

Background: The aim of this study was to compare the accuracy of apex locator, digital periapical radiography, and cone-beam computed tomography (CBCT) for determining the root canal working length (WL) in teeth with external root resorption (ERR). Materials and Methods: In this in vitro study, the sample consisted of 54 extracted permanent single-rooted human teeth. ERRs were performed at the 3 mm apical root using 65% of nitric acid for 24 h. After determining the actual WL by K-file #10 (gold standard) with the visualization method, the teeth were mounted in alginate and the WL of each tooth was determined using the electronic apex locator (EAL) equipped with a K-file #15. The teeth were mounted with wax in the teeth sockets of a dry human mandible, and the images were obtained by digital phosphor plate receptors and CBCT scans. The mean registered WL of each method was statistically compared with the gold standard WL using one-way ANOVA with P < 0.001. Results: The mean ± standard deviation (SD) of actual WL was 16.00 ± 2.24. The mean ± SD of WLs determined by CBCT, EAL, and digital radiography were 15.38 ± 2.19, 15.52 ± 2.32, and 16.83 ± 2.20, respectively. This study showed that the mean measured WL with ERR in all methods was significantly different from the actual WL (P < 0.001). Conclusion: This study showed that there was a significant difference between the actual mean WL and the EAL, digital periapical radiography, and CBCT mean WL. Thus, the combination of EAL and CBCT could be a reliable method for determining WL in the presence of ERR.

With the continuous improvement of broiler production performance, the frequent occurrence of leg problems has caused serious economic losses in many factories. In order to more efficiently detect and prevent broiler leg diseases, we propose an auxiliary detection system for broiler leg diseases based on deep learning. The system is divided into two parts. First, a digital radiography (DR) image of a broiler is taken through industrial computed tomography (CT), and then the improved deep-learning network Tibia-YOLO is used to detect the tibia; the detected results are then extracted and measured. Our improved Tibia-YOLO network uses the Content-Aware ReAssembly of Features (CARAFE) upsampling operator to avoid checkerboard artifacts and increase the generalization capabilities. Efficient multi-scale attention (EMA) and parallel network attention (ParNet) were added to the Tibia dataset at multiple scales (COCO2016), and there were improvements when testing on the three VOC2012 datasets. The mean average precision of tibia detection reached 90.8%, and the root mean square error (RMSE) for the tibia length was 3.37 mm.

AIM: Artifacts (error) encountered in phosphor plates (PSP) used in intraoral digital imaging were evaluated under a new classification. METHODS: In our study, when obtaining images with intraoral phosphor plates, artifacts before, during, after the irradiation and artifacts caused by the scanner were determined according to review of the literature. RESULTS: Intraoral radiographs are obtained while many artifacts are encountered. These artifacts can occur in both conventional and digital systems. Artifacts that ocur before irradiation such as scratches, cracks, fingerprints, dust particles, bite marks, plate edge peeling; during irradiation such as positioning error, motion artifact, shooting from different angles errors, cone-cut, double image, light-dark images, glare, fading, revers irradiation , refraction, distortion; after irradiation such as irregular image density, noise, writing artifact, fingerprints, fading artifacts; and depending on the scanner artifacts such as inclined placement, a parallel line to scan direction, dust fragment, plate size determination error has been shown to be visible. CONCLUSION: An inaccurate image with no diagnostic value requires regeneration. For this reason, knowing the causes of artifacts in radiographic images is important for the patient, the environment, and the practitioner to prevent unnecessary x-rays (radiation).

Introduction: Inexperienced undergraduate dental students tend to take unnecessary radiographs during endodontic treatment, which has an adverse effect on clinical workflow. The aim of this study was to quantify the repeat rate of endodontic periapical radiographs taken by senior dental students during endodontic treatment stages and to analyze the prevalence of radiographic errors that led to repeated radiographs. In addition, the average number of visits required to complete the treatment was determined. Materials and Methods: A total of 583 cases that included 5689 periapical radiographs were collected from the records of a completed academic year. The periapical images were divided according to tooth type and the stages of the treatment procedure. The prevalence of error types, number of visits, and repeated images exceeding the number of radiographs allowed for completion of the treatment were evaluated. The collected data were statistically analyzed. Results: The overall repeat rates of anterior, premolars, and molars were 36%, 36%, and 39%, respectively (P = 0.66). The highest repeat rates were recorded during instrumentation (44%-55%), followed by obturation (36%–46%). The most common error types were working length adjustment (27%–33%), missing apex (24%–28%), and obturation adjustment (19%–24%). The mean number of visits was higher than recommended for all tooth types. Conclusions: The repeated rates of radiographs and number of visits were higher than recommended. A set of recommendations were formulated to optimize quality assurance and deliver a better-quality health service to the patients.

Abstract Background This study aimed to investigate the effect of automatic exposure compensation (AEC) of intraoral radiographic systems on the gray values of dental tissues in images acquired with or without high-density material in the exposed region using different exposure times and kilovoltages. The influence of the distance of the high-density material was also investigated. Methods Radiographs from the molar region of two mandibles were obtained using the RVG 6100 and the Express systems, operating at 60 and 70 kV and 0.06, 0.10, and 0.16 s. Subsequently, a titanium implant was inserted in the premolar’s socket and other images were acquired. Using the ImageJ software, two regions of interest were determined on the enamel, coronary dentine, root dentine, and pulp of the first and second molars to obtain their gray values. Results In the RVG 6100, the implant did not affect the gray values (p > 0.05); the increase in kV decreased it in all tissues (p 0.05). Conclusions AEC’s performance varies between the radiographic systems. Its effect on the gray values depends not only on the presence or absence of high-density material but also on the kV and exposure time used.

Background/Aim: Radiopacity of dental restorative materials is significant to detect secondary caries, overhangs, and voids. This study aimed to evaluate whether radiopacity of dental restorative materials used in pediatric dentistry was sufficient. Material and Methods: Specimens of 2 mm thickness and 4 mm diameter were prepared in the plastic molds. Six composite materials, one compomer material, and one conventional glass ionomer cement were used and three specimens of each material were prepared. Three radiographs were taken from dental restorative materials and aluminum step wedge. Digital images obtained were recorded. Mean gray values of the dental restorative materials and aluminum step wedge were measured on digital radiographs. Results: All composite resins displayed higher radiopacity values than an equal thickness of 2 mm Al. Posterior composite (201.62±1.99 MGV) showed higher radiopacity value than the anterior composite (86.19 ±1.45 MGV). There was no significant difference in radiopacity values of different shades of the same composite. There was no significant difference in radiopacity values between glass ionomer cement and compomer. Glass ionomer cement showed higher radiopacity value (8.11 mm Al) than anterior composite (5.31 mm Al). Conclusions: Radiopacity values of dental materials used in this study were sufficient. Both resin materials and the glass ionomer cement had sufficient radiopacity values. Posterior composite showed the highest radiopacity value. Radiopacity values were not affected by different shades.

Purpose: To evaluate the image quality of semi-anatomical chest radiographs acquired using low radiation doses from seven different flat-panel detector (FPD) systems. Materials and Methods: Radiographs of a semi-anatomical chest phantom were acquired at 70 and 110 kVp using 7 different FPDs from 5 vendors. Radiation doses were measured using a dose-area-product (DAP) meter. To standardize measurements across all FPDs, DAP value of 51.05 μGym2 obtained at 70 kVp and 9.43 μGym2 at 110 kVp was used as reference in this study. Radiation doses were reduced by manually adjusting mAs for both tube potentials in all FPD systems to achieve acceptable image quality. Contrast-to-noise ratio, signal-to-noise ratio and figure of merit (FOM) in lung, heart, and diaphragm for all images were analyzed. Results: In comparison with set standard protocol, radiation dose reduction of 20%, 21%, 21.6%, 59.5%, 60.7%, 62.2%, and 67.6% with optimal image quality was observed in Prognosys Prorad, GE Definium 8000, Siemens Fusion, Fujifilm FGX, Fujifilm FGXR, Philips Digital Diagnost and Siemens Aristos at 70 kVp. At 110 kVp, dose reduction of 15.7% and 34.8% was possible only for Philips Digital Diagnost and Siemens Aristos. FOM was high at 110 kVp even when radiation doses were reduced by a factor 2 when compared to 70 kVp in all digital radiography systems. Conclusion: This study demonstrates the feasibility of using a semi-anatomical chest phantom in the optimization of radiation dose and image quality. The FOM was a good indicator in assessing image quality between different detectors.

The purpose of the work presented was to evaluate the capabilities of digital radiography to detect cracks in the internal structure of MiG-29 vertical stabilizers. The test object was a stabilizer previously subjected to fatigue testing and partially torn down for the needs of visual inspection. An inspection of three regions containing cracked parts was performed, with use of a pulsed x-ray generator and digital detector array. The results confirmed the method could be used to detect cracks in an internal structure which could not be inspected with other methods without affecting the stabilizer’s integrity.

Abstract Introduction Pre‐operative templating using digital radiography is an effective method of planning for total hip arthroplasty (THA) and requires a generalised fixed magnification factor (MF) or external calibration markers (ECM). The effect on image magnification when changing source‐to‐image distance (SID), object‐to‐image distance (OID) and different imaging conditions is not well described. This study aims to quantify the range of effects manipulation of radiographic parameters can have on image magnification across different body habitus and imaging conditions. Methods A simple phantom study was performed. A 25 mm ECM was placed at eight different OID values along the anterior–posterior phantom plane at three different SID values and imaging conditions, and X‐rays were obtained. On each radiograph, the ECM was measured using a line calliper tool by three radiographers and recorded. The MF was calculated and recorded. Results The smallest observed image MF was 1.16, for an 8 cm OID, 120 cm SID with the ECM placed within the central ray and the X‐ray detector in bucky underneath the X‐ray table. The largest image MF was 1.40 for a 15 cm OID, 100 cm SID with the X‐ray detector placed underneath an emergency department imaging trolley. Conclusions Digital pre‐operative templating for THA relies on accurate radiographic positioning and is dependent of the patient body habitus, radiographic parameters and imaging conditions selected by the radiographer. The use of appropriately positioned ECMs – placed medially between the patient’s internally rotated legs at the level of the greater trochanter, lowers the potential for magnification inaccuracies.

Abstract Introduction The largest source of manmade ionising radiation exposure to the public stems from diagnostic medical imaging examinations. Reject analysis, a form of quality assurance, was introduced to minimise repeat exposures. The purpose of this study was to analyse projection‐specific reject rates and radiographic examinations with multiple rejects. Methods A retrospective audit of rejected radiographs was undertaken in a busy Australian metropolitan emergency digital X‐ray room from March to June 2018. The data were collected by reject analysis software embedded within the X‐ray unit. Reject rates, and reasons for rejection for each X‐ray projection were analysed. Results Data from 11, 596 images showed overall reject rate was 10.3% and the overall multiple reject rate was 1.3%. The projections with both a high number and high percentage of rejects were antero‐posterior (AP) chest (175, 18.1%), AP pelvis (78, 22.5%), horizontal beam hip (61, 33.5%) and horizontal beam knee (116, 30.5%). The projections with both a high frequency and multiple reject rate were horizontal beam knee (32, 8.4%) and horizontal beam hip (17, 9.3%). The top reasons for multiple rejects were positioning (67.1%) and anatomy cut‐off (8.4%). Conclusions The findings of this study demonstrated that projection‐specific reject and multiple reject analysis in digital radiography is necessary in identifying areas for quality improvement which will reduce radiation exposure to patients. Projections that were frequently repeated in this study were horizontal beam knee and horizontal beam hip. Future research could involve re‐auditing the department following the implementation of improvement strategies to reduce unnecessary radiation exposure.

The elimination of necrotic and inflamed pulp tissue, dentin debris, and microorganisms is essential for the success of endodontic treatment. However, the root canal’s complexity has led to incomplete cleaning and disinfection. This study aims to compare the efficacy of the penetrability of three different irrigation activating techniques to the apical third of the root canal. Sixty sound single-rooted human mandibular premolars are prepared with rotary instrumentation under continuous sodium hypochlorite irrigation. Three irrigation activation techniques are utilized: group 1 (n = 20), conventional needle irrigation (CN); group 2 (n = 20), side-vented endodontic needle irrigation (EN); and group 3 (n = 20), manual activation irrigation with gutta-percha cone (MA). The penetrability is assessed with the aid of a radiopaque irrigation solution using digital radiography in conjunction with cone-beam computed tomographic (CBCT) measurements. Data are analyzed using a statistical package for social sciences (SPSS), using multiple comparisons to compare the baseline and test values. One-way analysis of variance with post hoc analysis (Tukey honestly significant difference) is performed to detect the statistically significant differences between groups. Manual activation (MA) shows effective delivery of the irrigant into full WL, followed by endodontic needle (EN) and conventional (CN) methods of activation (p < 0.001). The results of the present study show that maximum penetrability of the irrigant is observed with manual activation (MA) using a gutta cone in comparison with the conventional needle (CN).

Three different digital detector systems were used to study the effect of a defined radiation dose reduction on the image quality of digital radiographs in bearded dragons (Pogona vitticeps). A series of radiographs of seven bearded-dragon cadavers with a body mass ranging from 132 g to 499 g were taken in dorsoventral projection. The digital systems employed included two computed radiography systems (CR) (one system with a needle-based and one with a powdered-based scintillator) and one direct radiography system (DR). Three levels of the detector dose were selected: A standard dose (defined based on the recommended exposure value of the CRP, D/100%), a half dose (D/50%), and a quarter dose (D/25%). Four image criteria and one overall assessment were defined for each of four anatomic skeletal regions (femur, rib, vertebra, and phalanx) and evaluated blinded by four veterinarians using a predefined scoring system. The results were assessed for differences between reviewers (interobserver variability), radiography systems, and dosage settings (intersystem variability). The comparison of the ratings was based on visual grading characteristic (VGC) analysis. Dose reduction led to significantly lower scores in all criteria by every reviewer, indicating a linear impairment of image quality in different skeletal structures in bearded dragons. Scores did not differ significantly between the different systems used, indicating no advantage in using a computed or direct radiography system to evaluate skeletal structures in bearded dragons. The correlation was significant (p ≤ 0.05) for interobserver variability in 100% of the cases, with correlation coefficients between 0.50 and 0.59. While demonstrating the efficacy of the use of digital radiography in bearded dragons and the similar quality in using different computed or direct radiography systems, this study also highlights the importance of the appropriate level of detector dose and demonstrates the limits of post-processing algorithm to compensate for insufficient radiation doses in bearded dragons.

Introduction: Determining working length had always been one of the most crucial factors in evaluating prognosis. Radiography as a gold standard way nowadays has some flaws like making a 3D object, image distortion, not measuring the exact location of apical foramen, and putting the patient in a direct X-ray exposure. Here, we compare these three ways in measuring working length of single canal teeth that are narrow. Methods: Initially thirty single canal teeth with narrow canals were selected. After preparing the access cavity, the teeth were mounted in alginate for measuring working length with an apex locator. After that, they mounted in chalk in order to determine the working length using conventional and digital radiographs. Finally, the teeth were removed from the mount and the exact working length assessed using a hand file to compare with the three mentioned methods. Results: This study showed that the mean measured working length of root canal therapy had a significant difference between the four methods (P=0.003). Bonferroni post hoc test showed that the mean exact working length of root canal therapy was significantly lower than measured working length of root canal therapy by conventional radiography (P=0.002), digital radiography (P=0.001) and Raypex6 apex locator (P=0.01). However, there was no significant difference between these three methods (P>0.05). Conclusion: The results of this study showed that the mean measured working length of root canal therapy had no significant difference between digital radiography, conventional radiography, and Raypex6 apex locator but these three methods had a significant difference with the exact teeth length

Introduction. World Health Organization announced that COVID-19 was a “public health emergency”. Тhe number of patients with COVID-19 and deaths from this disease are increasing every day, so the issue of diagnosis and treatment of this serious pathology remains relevant. Goal. To identify the key lung lesion patterns in patients with SARS-CoV-2 infection during digital radiological examination. To identify its capabilities in assessing the prevalence and dynamics of radiological manifestations of lung damage. Material and methods. The analysis of data of radiological examination of 1,075 patients with SARS-CoV-2 infection in moderate and severe conditions, who were treated in MNPE KRC “Regional Clinical Specialized Dispensary for Radiation Protection” in the period from June to November 2020 has been carried out. All the patients were given digital radiography at the time of treatment. To assess the dynamics the control examination depending on the clinical manifestations was held. The images were evaluated by two independent radio- logists. Pathological changes manifested in the form of matte, consolidation of parenchyma and reticular pattern. Results. The majority of the total number of the surveyed patients falls on the age group between 50 and 75 years old – 789 patients (73.4%). The most common pattern of lung lesion on the primary radiograph is a GGO symptom (82.7%), and in control examination there was an increase in the frequency of consolidation (53.4%), and then – fibrous changes of varying severity (62.5%). Bilateral lesion was detected in 74.8% of cases. Middle-lower and lower lobes of the lungs were more often affected. Conclusions. OCC CT should be used to detect pathological changes in COVID-19 in the early stages, and digital radiography can identify characteristic signs of lung lesion in inpatients with moderate to severe Coronavirus disease and is sufficient to assess the dynamics of the patholo- gical process. Digital radiography method should be included in the examination protocol of patients in moderate and severe conditions in the hospital due to the impossibility or difficulty of their transportation. If repeated examination in such patients is necessary much higher dose load on CT compared to digital radiography should be taken into account.

Background and Aims: Pulpal exposures originated from the external cervical root resorptions have major effects on the treatment and prognosis. Therefore, the aim of this study was performed to compare the two different imaging systems-digital radiography with PSP (Photostimulable Phosphor) sensor in three horizontal different views and CBCT (cone beam computed tomography) images to assess the pulpal exposure in simulated cavity of external cervical root resorptions that was performed in 1398 in the School of Dentistry of Azad University. Materials and Methods: 40 intact maxilla anterior teeth with straight roots were included. Teeth were randomly divided to two groups (20 teeth with and 20 without pulpal exposures). Each sample was assessed using PSP digital radiography (in 3 horizontal angles) and CBCT image system, to detect the presence of pulpal exposures. False negative and false positive results in 2 imaging procedures were judged with ratio test. Results: The results showed in CBCT (P.P.V=85.7%) and (N.P.V=89.5%), and in digital intraoral radiography (P.P.V=80%) and (N.P.V=80%) in proximal defects. Ratio test showed that there were no significant differences in the proximal defects (P

Canine stifle joint osteoarthritis (OA) is characterized by damage and degeneration of the articular cartilage and subchondral bone, bony hypertrophy at the margins, and synovial joint membrane changes. Non-invasive imaging modalities, such as digital radiography (DR), computed tomography (CT), and magnetic resonance imaging (MRI), can be used to describe these changes. However, the value of MRI in diagnosing spontaneous canine OA and the comparison of different imaging modalities have seldom been addressed. This study compared multiple noninvasive imaging modalities in canine spontaneous stifle OA cases. Four client-owned dogs with five spontaneously affected OA stifle joints were recruited and underwent DR, CT, and MRI. Information on osteophytes/enthesophytes, ligament/tendon lesions, synovial effusion and membrane thickening, subchondral bone lesions, and meniscal and cartilage lesions were scored and compared. The results showed that MRI provides the most comprehensive and superior lesion detection sensitivity for ligament, meniscus, cartilage, and synovial effusions. DR provides adequate bony structure information, while CT provides the most delicate images of bony structure lesions. These imaging findings may provide further understanding of the disease and help clinicians draft a more precise treatment plan.

Radiographic detection technology is a nondestructive detection technology widely used in industrial field and ithas unique advantages in qualitative defect detection and other aspects. According to the characteristics of defect imagingtechnology, the development status of the major industrial radiographic detection technologies was compared, the technicalcharacteristics and advantages of Digital Radiography (DR) detection were clarified, and the requirements of the relevantChinese standards for radiographic detection of long-distance pipeline were summarized from the aspect of weld inspectionand qualification certification. In these standards, slight difference existed in the requirements of detection proportion, butthe requirements of DR and RT-F were consistent in defect assessment. Herein, the application of DR technology in longdistance pipeline at home and abroad were introduced, the technical problems of DR detection technology for applicationin China were analyzed in the aspects of detection efficiency and economic benefits, selection of flat panel detector anddefect assessment, the future development trend of DR detection technology was prospected, and in combination withthe development trend of digital pipelines such as the China-Russia Eastern Gas Pipeline, the analysis indicates thatDR detection technology will play an increasingly important role in remote efficient assessment and detection big datamanagement and analysis, with broad application prospects.

Background. Dental caries is the most important reason for tooth loss. Clinical examination is the most commonly used technique for occlusal caries diagnosis. The diagnostic power of digital systems is a matter of controversy in this field. The present study aimed to determine the diagnostic accuracy of two photostimulable phosphor plate (PSP) systems for early occlusal dentin caries in vitro. Methods. Sixty-nine extracted molar and premolar teeth were used in this study. The teeth were mounted in triple blocks, and standard radiographs were taken by the Digora and Acteon digital radiographic systems. The original and filter 1-enhanced radiographs were evaluated by two experienced observers twice at an interval of two weeks, and dentin caries was recorded in Tables prepared for the study. The teeth were then sectioned in a buccolingual direction and evaluated under a stereomicroscope. The observers’ reports were compared with microscopic findings as the gold standard. SPSS 23 was used to calculate the kappa coefficient, sensitivity, specificity, and area under the ROC curve (AUC). Statistical significance was set at P

Background/Aim: The determination of remaining dentin thickness (RDT) is quite critical in providing appropriate treatment indications especially in deciduous molars. The aim of this study was to investigate the accuracy of in vitro pre-operative radiographs before caries removal in RDT measurement.

Abstract Background Osteoarthritis (OA) is the most commonly diagnosed joint disease in veterinary medicine, with at least 80% of the cases of lameness and joint diseases in companion animals being classified as OA. Sporting and working animals are more predisposed to develop OA since they are exposed to chronic fatigue injuries, leading to bone and muscular tissue damage and failure, resulting in clinical signs. To characterize the clinical signs and diagnostic findings of Police working dogs presenting with bilateral hip OA at the time of diagnosis. Fifty animals were evaluated with a bodyweight ≥ 15 kg, be older than two years, and without any medication or nutritional supplements for ≥ 6 weeks. Results Weight distribution, joint range of motion at flexion and extension, thigh girth, digital thermography, and radiographic signs were collected. Data from different Clinical Metrology Instruments (CMI) were collected: Canine Brief Pain Inventory, Liverpool Osteoarthritis in Dogs, Canine Orthopedic Index, and the Hudson Visual Analogue Scale. Results were compared by breed, age, sex, and Orthopaedic Foundation for Animals hip grades with the Independent Samples T-Test, ANOVA followed by a Bonferroni post hoc test, and Pearson correlation coefficient, with p

Radiological diagnostics serves as one of the basic monitoring techniques in veterinary dental practice. The recent up-to-date literature data based on the findings of digital radiology/radiovisiography (RVG) in general dentistry inspired the authors to present its possible use in clinical veterinary dentistry. The digital radiography used in this study was RVG Trophy Radiologie SA 2001 device equipped with software for linear measurements (readings), densitometry, setting of contrast of radiography image, 3D image manipulation, zooming of detail and orientation handling. The aim of the study was to evaluate the bone mineral density of the alveolar part of the lower jaw in seven Scottish terriers. Bone mineral density measurement was performed around the central lower incisors by converting gray scale values into equivalent aluminum thickness (mm Al). The mean bone mineral density was in the range of 4.31-6.20 mm Al with no significant statistical difference between left and right incisors (p>0.01). Our results showed that the combination of RVG and aluminum step wedge etalon is a reliable tool to measure bone mineral density around the lower central incisors in dogs. This method can be considered as comfortable for manipulation in everyday use in clinical veterinary practice.

Introduction: Panoramic radiograph is an image used by the dentist to maintain diagnosis in dentistry, for example, to evaluate teeth condition in mixed dentition period. There are two panoramic radiography techniques, which are conventional and digital (direct and indirect) method. This study was aimed to analyse the differences of panoramic radiograph image quality between the conventional and digital indirect method on mixed dentition radiograph. Methods: Thirty samples of conventional and indirect digital panoramic radiograph were randomly taken from the database according to inclusion criteria. The image quality of conventional radiograph was manually assessed by using illuminator box, while indirect digital radiographs was assessed directly using DBS Win 5.7.0 software (Durr Dental, Germany). The radiographs were divided into six zones: teeth area, nasal and sinus, mandible, TMJ, ramus-spine, and hyoid bone. The image quality assessment was performed in each area based on three criteria: anatomical coverage, density and contrast, and anatomical structure. Results: The Cronbach's Alpha Intra-Class Correlation (ICC) inter and intraobserver agreement test of conventional and digital indirect methods on the aspect of anatomical, density and contrast coverage, and anatomic structure showed an excellent agreement. The independent sample t-test result showed significant difference (p < 0.05) between the conventional and indirect digital method in density and contrast as well as anatomical structure aspects, but not significantly different (p > 0.05) in the anatomical coverage aspect. Conclusion: Indirect digital panoramic radiograph shows better image quality as compared to conventional radiograph, especially in the anatomical structure aspect, density and contrast. There is no difference in the anatomical coverage aspect between conventional and indirect digital panoramic radiograph.

Monte Carlo method is widely used for simulation of industrial and medical radiography due to its powerful ability to simulate statistical phenomena such as radiation generation and transport, and detection processes. Digital radiography is practically applied in two branches of computational radiography (CR) and direct radiography (DR). In this study, computational radiography simulation using the FLUKA Monte Carlo code was developed to provide a framework for studying image contrast as one of the most important parameters of image quality. To investigate the contrast a standard aluminum sensitivity component made of ASTM 1647 standard was used. The simulation of this gauge, along with a complete simulation of the X-ray generator and imaging plate, has been done to assess the image contrast, and and a method has been presented to examine the image contrast. In order to validate the proposed method, practical experiments have been carried out on the contrast sensitivity standard gauge. The simulation results obtained through the proposed method are in good agreement with the results of practical experiments.

Abstract Introduction Reject analysis in digital radiography (DR) helps guide the education and training of staff, influences department workflow, reduces patient dose and improves department efficiency. The purpose of this study was to investigate rejected radiographs at a major metropolitan emergency imaging department to help form a benchmark of reject rates for DR and to assess what radiographs are being rejected and why. Methods A retrospective longitudinal study was undertaken as an in‐depth clinical audit. The data were collected using automated reject analysis software from two digital x‐ray systems from June 2015 to April 2017. The overall reject rate, reasons for rejection as well as the reject rates for individual radiographers, examination types and projections were analysed. Results A total of 90,298 radiographic images were acquired and included in the analysis. The average reject rate was 9%, and the most frequent reasons for image rejection were positioning error (49%) and anatomy cut‐off (21%). The reject rate varied between radiographers as well as for individual examination types and projections. Conclusions The variation in radiographer reject rates and the high reject rate for some projections indicate that reject analysis is still necessary as a quality assurance tool for DR. A feedback system between radiologists and radiographers may reduce the high percentage of positioning errors by standardising the technical factors used to assess image quality. Future reject analysis should be conducted regularly incorporating an exposure indicator analysis as well as retrospective assessment of individual rejected images.

Context: The device for dental radiographic standardization (DDRS) was developed to minimize the distortions in conventional periapical radiographs or digital subtraction, improving the effectiveness of the technique. Objectives: The objective of this study is to present the DDRS and prove its effectiveness through comparative test, performed with the techniques of Bissetrix and Parallelism. Configurations and Design: The DDRS adapts to the universal radiographic positioner, is economical, and easy to operate. It is recommended for the use in research, where standardization is a requirement. Subjects and Methods: DDRS is produced using the additive manufacturing method for prototyping, after creating a three-dimensional (3D) model using a specific program (Autodesk Inventor 2016, Autodesk, Inc, California, USA). The final prototype was converted to the STL format, which was later read by a 3D printer (3D Machine ONE, São Paulo, Brazil). To perform the tests, three radiographic techniques were compared, Bisecting angle technique, parallelism and DDRS fitted to the universal positioner, and two examiners performed the evaluation independently. Statistical Analysis Used: Differences between the techniques were compared by the analysis of variance, followed by Dunnett’s multiple comparisons. The variability of the measured values among the techniques was compared by the Levene’s test. The intraclass correlation coefficients were calculated to evaluate the reproducibility and interexaminer agreement for each technique and parameter. Results: DDRS eliminates the effect of distortion factors that normally affect conventional methods, allowing greater reliability in the interpretation of the image before, during, and after treatment. Conclusions: The DDRS should be used for clinical and routine research purposes, facilitating comparisons of the same image at different time intervals, with minimized errors of vertical and horizontal angulation. This allows greater reliability in the interpretation of the image in relation to the structures of interest.

Background: The aim of this study was to compare the image quality and radiation doses in various digital radiography systems using contrast-detail radiography (CDRAD) phantom. Methods: The image quality and radiation dose for seven different digital radiography systems were compared using the CDRAD phantom. Incident air kerma (IAK) values were measured for certain exposure settings in all digital radiography systems. The images from the CDRAD phantom were evaluated by three observers. The results were displayed in the form of a contrast-detail (CD) curve. In addition, the inverse image quality figure (IQFinv)-to-IAK ratios were used for quantitative comparison of different digital radiography system performance. Results: Results of this study showed that the CD curves cannot be suitable criterion for determining the performance of digital radiography systems. For this reason, IQFinv-to-radiation dose (IAK) ratios in a fixed radiation condition were used. The highest performance in terms of producing high-quality images and low radiation dose was related to X-ray unit 1 and the lowest performance was for X-ray unit 5. Conclusion: The ratio of IQFinv to IAK for performance evaluation of digital radiography systems is an innovation of this study. A digital radiography system with a higher IQFinv-to-IAK ratio is associated with lower patient dose and better image quality. Therefore, it is recommended to equip the new imaging centers with the systems that have higher IQFinv-to-IAK ratios.

Background: Given that the world's population is aging, the problems associated with osteoporosis and related fractures are increasing. The aim of the study was to evaluate the effect of flaxseed extract on bone mineral density (BMD) in Wistar rats using digital radiography. Methods: In this experimental study, 25 male and 25 female Wistar rats were randomly divided into 5 groups: 1. Control, 2. Calcium and vitamin D (Ca/VitD), 3. 100 mg/kg flaxseed, 4. 200 mg/kg flaxseed, and 5. 400 mg/kg flaxseed. Then, the animals were kept for thirty days. Maxillary and mandibular BMD as well as serum levels of calcium, vitamin D and phosphorus were measured at baseline and after 30 days of keeping the rats. Results: The results showed that serum levels of calcium and phosphorus were not significantly different in all five groups before and after 30 days. Serum levels of vitamin D were significantly higher in the group receiving Ca/vit D (with a mean of 61.6±15.8 in the male group and 85±12.9 in the female group) as compared with other groups (P

Background: Two-dimensional intraoral radiography is the most common tool for recognizing root fractures. Improving the quality of images by means of enhancement tools can increase the recognition power of them. The aim of this study is to evaluate the effect of digital image enhancement on vertical and horizontal root fractures (HRFs) diagnostic accuracy. Materials and Methods: In this in vitro study, 100 human extracted teeth, involving 50 mandibular premolars and 50 maxillary incisors, were investigated. In total, 25 premolar teeth were vertically fractured and other 25 sound teeth served as testing group. According to the verified methods, 25 incisor teeth were fractured and other 25 teeth of this group served as testing ones. Following, by using the charge-coupled device sensor, preapical digital images were recorded. The original images were altered using reverse-contrast and colorization enhancement tools. Two different observers independently investigated all of the images. Receiver operating characteristic analysis was used to calculate the area under the curve (AUC) and sensitivity and specificity of all images. Data analyzde using receiver operating characteristic (ROC) analysis. Two-ways variance analysis was used to assess differences in the values (P = 0.05 ). Results: AUC and sensitivity and specificity related to the original, reverse-contrast, and colorized images were calculated (0.84, 0.64, 0.99), (0.84, 0.64, 0.96), and (0.82, 0.64, 0.92) respectively, for vertically root fractured images. AUC and sensitivity and specificity related to the original, reverse-contrast, and colorized images were calculated (0.49, 0.44, 0.56), (0.50, 0.44, 0.60), and (0.48, 0.48, 0.48), respectively, for horizontally root-fractured images. Conclusion: The results of the present study revealed that reverse-contrast and colorized enhancement filters cannot be used as critical methods in detecting in vitro vertical and HRF.

Background: Autogenous bone graft is the gold standard for repair of bone defects. However, osteoprogenitor stem cells are suggested as an alternative treatment. Aims: To quantitatively compare bone formation in autogenous bone graft and tissue-engineered graft using digital radiography densitometry software in canine alveolar cleft model. Setting and Design: This experimental study on animal models was conducted in Isfahan University of Medical Sciences. Methods: Mesenchymal stem cells (MSCs) were obtained from subcutaneous adipose tissue of 4 dogs. Undifferentiated cells were incubated with a hydroxyapatite/beta-tricalcium phosphate scaffold in an osteogenic medium for 21 days. A maxillary defect simulating human alveolar cleft was created from the alveolar crest to nasal floor with 15 mm width bilaterally. Two months later, the defect was filled with autogenous bone graft harvested from tibia on one side and tissue-engineered graft from MSCs on the other side. Digital radiography was performed on days 15, 30, 45, 60, 75, and 90 after grafting. Radiographic density was calculated by the mean numeric value of pixels of the desired area ranging from 0 (darkest) to 255 (lightest) by associated software. Statistical Analysis Used: The data were analyzed by Statistical Package for the Social Sciences using descriptive statistics and two-way repeated-measure analysis of variance test (α = 0.05). Results: Mean density measured for autogenous bone graft group was 110.72, 82.70, 75.76, 93.57, 100.22, and 100.32 in days 15, 30, 45, 60, 75, 90, respectively and 120.7, 87.62, 83.72, 92.02, 92.30, and 93.77 in stem cell group. Although the time lapse was a significant factor in two groups (P = 0.01), the results indicated that the difference between two groups was not statistically significant (P = 0.942). Conclusion: Tissue-engineering can be used as an alternative method in reconstruction of bony defects with predictable clinical outcomes.

Background: Digital imaging has the potential to improve diagnostic accuracy and make quantitative diagnoses. In the recent decades, software for radiographic analysis has been investigated and developed for the detection of lesions and the quantitative assessment of the depth of a caries lesion. In addition, the accuracy of diagnosis may also be enhanced by programs that filter the images. These programs can adjust the brightness and contrast, determine the gray level, invert the shades of gray, and apply pseudocolors. Few studies compared different types of digital images in the diagnosis of changes in the tooth crown. Aim: The main aim of this study was to assess the the diagnostic accuracy of a direct digital radiography (DDR)-CMOS image with four types of filtered images for the detection of occlusal caries. Materials and Methods: Fifty randomly selected patients' teeth were clinically examined and digitally radiographed. Radiographed images are converted into four filter images with the help of software. Filtered images were then selected for inter- and intraobserver examination and the result was subjected to statistical analysis. Conclusion: DDR-CMOS and negative image were found to be more useful in diagnosing occlusal caries.

Background: The aim of this study is to evaluate the level of knowledge and attitudes about digital radiography and Cone Beam Computed Tomography (CBCT) of Marmara University 4th and 5th grade students as a result of their education.Methods: In our study, a questionnaire consisting of 16 questions was applied to 100 4th and 100 5th grade students totally 200 students who are educated in Marmara University Faculty of Dentistry. Besides the knowledge level of the students, their attitudes were evaluated.Results: In our study, there was statistically significant difference between the responses given to “What source or sources do you know about CBCT?”, “How much do you think CBCT will be used in routine dental practice in the near future?”, “In which cases do you prefer to use CBCT in your future clinical life?”, “Would you prefer to use CBCT in your future professional clinical life?”, “According to you, in what year of dental training should CBCT be taught?” between 4th and 5th grade students (p

Background: Dose optimisation is a radiation protection guideline recommended by the International Commission on Radiological Protection (ICRP) for adherence to the ‘as low as reasonably achievable’ (ALARA) principle. Diagnostic reference levels (DRLs) are used to optimise patients’ radiation protection for diagnostic and interventional procedures and are particularly useful for frequently performed examinations such as chest X-rays. Aim: To establish the local diagnostic reference levels (LDRLs) for routine chest X-rays. Setting: Public sector hospital, Northern Cape province, South Africa. Methods: Sixty patients referred for chest X-rays fulfilling the inclusion criteria participated in this study. Patients were ≥ 18 years of age and weighed between 60 kg and 80 kg. Consent for participation was obtained. The entrance skin air kerma (ESAK) was measured by using the indirect method recommended by the International Atomic Energy Agency (IAEA). Statistical software (SAS version 9.2) was used to determine the LDRLs for chest X-rays in three different rooms. In two rooms, computed radiography (CR) was used and the other one was a digital radiography (DR) unit. The LDRL values at the research site were compared with various published international values. Results: LDRLs for chest X-rays were established. The CR LDRL value for the posteroanterior (PA) chest projection was higher than the DR (flat panel detector [FPD]) LDRL value. The LDRLs of the PA chest projections were 0.3 mGy for CR and 0.2 mGy for DR. The lateral (LAT) chest projection LDRL value was 0.8 mGy for both CR and DR (FPD) projections. The resultant LDRL between rooms at the research site was 0.3 mGy for PA 0.3 mGy and 0.8 mGy for LAT chest projections. Conclusion: The LDRLs for chest X-rays established at this research site were lower than internationally reported DRLs. We recommend that LDRLs for routine chest X-rays should be repeated every 3 years, according to the ICRP. Contribution: Currently, no established or published DRL values prescribed by the Directorate of Radiation Control (DRC) are available in South Africa. The LDRLs established for routine chest X-ray examinations at this research site can serve as a guideline for the establishment of DRL values for other anatomical regions at the research site and other radiology departments in the country.

Low-dose exposure and work convenience are required for mobile X-ray systems during the COVID-19 pandemic. We investigated a novel X-ray detector (FXRD-4343FAW, VIEWORKS, Anyang, Korea) composed of a thin-film transistor based on amorphous silicon with a flexible plastic substrate. This detector is composed of a thallium-doped cesium iodide scintillator with a pixel size of 99 μm, pixel matrix of 4316 × 4316, and weight of 2.95 kg. The proposed detector has the advantages of high-noise characteristics and low weight, which provide patients and workers with an advantage in terms of the dose and work efficiency, respectively. We performed a quantitative evaluation and an experiment to demonstrate its viability. The modulation transfer function, noise power spectrum, and detective quantum efficiency were identified using the proposed and comparative detectors, according to the International Electrotechnical Commission protocol. Additionally, the contrast-to-noise ratio and coefficient of variation were investigated using a human-like phantom. Our results indicate that the proposed detector efficiently increases the image performance in terms of noise characteristics. The detailed performance evaluation demonstrated that the outcomes of the use of the proposed detector confirmed the viability of mobile X-ray devices that require low doses. Consequently, the novel FXRD-4343FAW X-ray detector is expected to improve the image quality and work convenience in extended radiography.