Luminescence features of Ho3+ , Er3+ and Tm3+ ions in red lead added non-conventional antimony oxide glass system.

In this study, a glass system based on heavy metal oxides, namely Pb3 O4 -Sb2 O3 -SiO2 , was prepared with Ho2 O3 , Er2 O3 , and Tm2 O3 as dopants. The prepared glass were characterized using X-ray diffraction (XRD) and infrared (IR) studies. The luminescence efficiencies of the three rare earth ions viz., Ho3+ , Er3+ , and Tm3+ in the glass system were investigated, specifically focusing on green (Ho3+ , Er3+ ), blue (Tm3+ ), and near-infrared (NIR) emissions. The optical absorption (OA) and photoluminescence (PL) spectra of RE mixed glass displayed strong bands in the visible and NIR regions, which were analyzed using the Judd-Ofelt (J-O) theory. The J-O coefficients (Ωλ ) were found to be in the order of Ω2 > Ω4 > Ω6 for all the three glass. Notably, the Tm3+ -doped glass exhibited the lowest Ω2 value, which was attributed to a larger degree of disorder in the glass network due to lower fractions of Sb5+ and Pb4+ ions that take part in the glass network forming. This conclusion was arrived based on the IR studies. Furthermore, the quantitative analysis of PL spectra and decay curves indicated that SbHo and SbEr glass were suitable for efficient green emission, while SbTm glass is a promising choice for blue laser emission.

Detection of extracranial and intracranial calcified carotid artery atheromas in cone beam computed tomography using a deep learning convolutional neural network image segmentation approach.

OBJECTIVE: We leveraged an artificial intelligence deep-learning convolutional neural network (DL CNN) to detect calcified carotid artery atheromas (CCAAs) on cone beam computed tomography (CBCT) images. STUDY DESIGN: We obtained 137 full-volume CBCT scans with previously diagnosed CCAAs. The DL model was trained on 170 single axial CBCT slices, 90 with extracranial CCAAs and 80 with intracranial CCAAs. A board-certified oral and maxillofacial radiologist confirmed the presence of each CCAA. Transfer learning through a U-Net-based CNN architecture was utilized. Data allocation was 60% training, 10% validation, and 30% testing. We determined the accuracy of the DL model in detecting CCAA by calculating the mean training and validation accuracy and the area under the receiver operating characteristic curve (AUC). We reserved 5 randomly selected unseen full CBCT volumes for final testing. RESULTS: The mean training and validation accuracy of the model in detecting extracranial CCAAs was 92% and 82%, respectively, and the AUC was 0.84 with 1.0 sensitivity and 0.69 specificity. The mean training and validation accuracy in detecting intracranial CCAAs was 61% and 70%, respectively, and the AUC was 0.5 with 0.93 sensitivity and 0.08 specificity. Testing of full-volume scans yielded an AUC of 0.72 and 0.55 for extracranial and intracranial CCAAs, respectively. CONCLUSION: Our DL model showed excellent discrimination in detecting extracranial CCAAs on axial CBCT images and acceptable discrimination on full-volumes but poor discrimination in detecting intracranial CCAAs, for which further research is required.

Pseudopathologic findings on panoramic radiographs and utility of follow-up cone beam computed tomographic scans: a case series.

Conventional radiography is the mainstay for evaluation of developmental and pathologic disorders of oral and maxillofacial structures. Occasionally, clinicians may experience diagnostic pitfalls during interpretation of these imaging modalities. The aim of this article is to present 4 cases of pseudopathologic disorders found on intraoral and panoramic radiographs. Subsequent use of cone beam computed tomographic (CBCT) imaging determined that the initial concerning findings represented anatomical or radiographic anomalies rather than pathologic processes. Supplemental use of CBCT scans may enhance diagnostic assessment, possibly reducing the need for surgical intervention, and elucidate structurally compromised regions of the jaw that could predispose it to fracture.

Traumatic events in childhood and adulthood in a diverse-ancestry sample and their role in bipolar disorder.

We examined the presence of adverse events in both childhood and adulthood and the prevalence of PTSD in individuals with Bipolar Disorder (BD). There were 191 adults diagnosed with BD Type I and 924 controls, of predominantly African Ancestry (AA). All were administered the GPC-Screening Tool and the BD group the DIPAD. In addition Childhood adversities were measured using the ACE (from 0 to 10), about traumatic events before age 18 and lifetime adversities were measured with 15 questions adapted from the Study of Addiction: Genetics and Environment (A-SAGE (from 0 to 15) for all cases and controls. Probable PTSD (pPTSD) was measured with 4 questions on the GPC screener. Sum scores were calculated for the ACE and A-SAGE by tallying positive responses. Odd Ratios (OR) were used to measure the association between BD and Controls exposure to adversity. BD was associated with a significantly higher mean ACE score and A-SAGE score compared to controls. There was a significantly higher prevalence of pPTSD in the BD (54.5%) versus Controls (6.6%) as well. Greater OR's were seen in the BD compared to Controls for each ACE question (p<0.05). Results were similar for A-SAGE. Limitations include possible recall bias, and missing data.

Amplification of blue emission of Tm3+ ions in Li2 O-HfO2 -SiO2 glass system by means of Au0 metallic particles.

Li2 O-HfO2 -SiO2 -Tm2 O3 :Au2 O3 glass samples (containing fixed content of Tm2 O3 and different concentration of Au2 O3 ) were prepared and characterized. Bearing of Au0 metallic particles (MPs) on improving blue emission of thulium ions (Tm3+ ) ions was explored. Optical absorption (OA) spectra exhibited multiple bands excited from 3 H6 of Tm3+ . Additionally, a broad peak in the wavelength range 500-600 nm due to surface plasmon resonance (SPR) of Au0 MPs was noticed in the spectra. Photoluminescence (PL) spectra (of thulium free glasses) indicated a peak in the visible range due to sp → d electronic transition of Au0 MPs. Luminescence spectra of Tm3+ and Au2 O3 co-doped glasses exhibited intense blue emission with substantial increase of intensity with increase of Au2 O3 content. Bearing of Au0 MPs on the reinforcement of blue emission of Tm3+ was discussed in detail with kinetic rate equations.

Influence of nanosized defects on photoluminescence efficiency of Er3+ ions co-doped with Au2 O3 in a lead boroselenate glass ceramic system: a novel approach using positron annihilation lifetime spectroscopy.

This study consists of the results of an investigation into the influence of the free-volume space (fv ) defects on luminescence efficiency (LE) of erbium ions in Au2 O3 -doped PbO-B2 O3 -SeO2 (PBS) glass ceramics. Glass ceramics containing fixed concentrations of Er3+ ions and varied concentrations of Au2 O3 were synthesized. X-ray diffraction studies indicated that the samples contained Au2 (SeO3 )3 crystalline phase and nano gold metallic particles. The concentration of defects entrenched in the glass ceramics estimated in terms of Au2 O3 content using positron annihilation lifetime spectroscopy measurement indicated the highest content in the glass ceramic containing 0.075 mol% of Au2 O3 . Optical absorption and the photoluminescence (PL) spectra of the glass ceramics were studied in the visible region. The observed increase of PL efficiency was attributed to the enhanced concentration of free-volume imperfections in the samples. A perfect correlation could be achieved between the free-volume fraction and the PL efficiency of erbium ions in these glass ceramics.

Radiographic presentation of artifactual dyed hair on lateral cephalograms, chemical processing, and forensic application: Novel case report.

Forensic assessment employs an array of methods to identify human remains. Radiologic examinations with panoramic radiographs, computed tomography scans, Waters view, and nuclear magnetic resonance imaging may offer evidentiary clues in challenging cases, such as mass disasters. In these cases, alternative forensic tools are used to narrow lists of target victims using their biological features. This study aims to I) report on the unusual radiographic aspect of chemicals used for hair dyeing, and II) discuss the potential forensic application of this finding for human identification. The case depicts an asymptomatic 14-years-old female who presented for orthodontic therapy. During radiographic examination on a lateral cephalogram, numerous thin radiopaque streaks were visible, extending to the posterior neck between the occipital region of the skull base and vertebra C6. Clinical investigations revealed that these were artifactual hair images (possibly documented for the first time in the scientific literature). Inductively coupled plasma mass spectrometry (ICP-MS) analysis of the patient's scalp hair was performed for 10 heavy metals, including zinc, copper, iron, chromium, nickel, cadmium, tin, lead, antimony, and bismuth. Eight of these metals were detected at normal levels, ranging from 160 parts per million (ppm) for zinc to less than 1 ppm for nickel, cadmium, tin, lead, and antimony. Conversely, slightly elevated levels of chromium at 0.41 ppm and bismuth at 0.025 ppm were found in the hair sample. The distinctive radiographic presentation of artifactual hair images combined with the chemical properties of hair exposed to dye products may provide useful traces for human identification, especially in mass disasters.

Value of Performing Routine Vascular Mapping Synchronous with Radiographic Assessment of Endodontic Lesions: Case Series.

With the adoption of limited-volume cone beam computed tomographic (CBCT) imaging in dentistry, high resolution of the maxillomandibular complex has led to the recognition of numerous accessory neurovascular canals. The preoperative identification of these structures is essential to facilitate the safe performance of an assortment of invasive dental procedures; however, there is limited information in the endodontic literature regarding mapping of these neurovascular canals and their anatomic variants. To emphasize the utility of accessory neurovascular channel mapping in conjunction with endodontic therapy, we have presented the clinical findings of 4 diverse cases. Comprehensive evaluation of the CBCT scans showed relevant underlying etiopathologies, prompting clinical modifications that led to enhanced patient outcomes.

Guidelines for oral and maxillofacial imaging: COVID-19 considerations.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing the current coronavirus disease 2019 (COVID-19) pandemic, is not only highly infectious but can induce serious outcomes in vulnerable individuals including dental patients and dental health care personnel (DHCPs). Responses to COVID-19 have been published by the Centers for Disease Control and Prevention and the American Dental Association, but a more specific response is required for the safe practice of oral and maxillofacial radiology. We aim to review the current knowledge of how the disease threatens patients and DHCPs and how to determine which patients are likely to be SARS-CoV-2 infected; consider how the use of personal protective equipment and infection control measures based on current best practices and science can reduce the risk of disease transmission during radiologic procedures; and examine how intraoral radiography, with its potentially greater risk of spreading the disease, might be replaced by extraoral radiographic techniques for certain diagnostic tasks. This is complemented by a flowchart that can be displayed in all dental offices.

Predoctoral Curricular Revision for Dental Radiographic Interpretation Competence Based on OSCE Results.

Teaching radiographic interpretation skills to predoctoral dental students is challenging. The results of an objective structured clinical examination (OSCE) at one U.S. dental school failed to yield expected outcomes for students' radiographic interpretation skills. The purpose of this article is to describe the development of the radiology OSCE and subsequent curricular revisions based on the outcomes. Examples of curricular changes are a series of self-assessed radiographic interpretation cases using the university learning management system. Each case contains a set of four intraoral radiographs and a series of questions. In year 4, an OSCE and final radiographic interpretation competency exam are administered; students are required to pass both exams. OSCE outcomes over a period of six years were used to evaluate the effectiveness of the curricular revisions. A questionnaire developed to capture student perceptions of the curricular changes was administered. The pilot OSCE of 2.9% first attempt pass rates initiated curricular revision. The strongest results to date occurred in 2018 with a 73.3% first attempt pass rate. Results from the questionnaire showed that students reported greater confidence in their interpretation skills when it came to recognizing radiographic errors, dental caries, and periodontal disease/pathologies (65%, 64%, and 57%, respectively). The use of the OSCE for programmatic assessment revealed the need for curricular revision in radiology. Students' participation in the newly revised radiology curriculum resulted in improved student performance and outcomes. This article emphasizes the importance of global and programmatic assessment for assessing student competence along with analysis of how assessment and accompanying data can inform curricular decisions.

Dental anomalies in pediatric patients with familial adenomatous polyposis.

Familial adenomatous polyposis patients often present with non-malignant extra-intestinal manifestations which include dental anomalies that may be evident prior to the appearance of the colonic adenomas. The aims of this study were to describe the prevalence and type of dental anomalies and the relationships between gene mutations and dental anomalies in these patients. Twenty-two pediatric familial adenomatous polyposis patients and 46 controls, who were age and gender matched participated. Familial adenomatous polyposis patient's had a dental examination with panoramic radiograph and medical record review for age at diagnosis, the presence of the adenomatous polyposis coli gene mutation, and determination of other extra-intestinal manifestations on the body. The control group was identified from a retrospective chart review and selected if there was a current panoramic radiograph. The only significant difference between familial adenomatous polyposis patients and controls were the presence of jaw osteomas and sclerosis (p = .0001). Patients with a mutation in, or upstream of codon 1309 had a higher frequency of osteomas (77.8%) and jaw-bone sclerosis (44.4%), and 77% of these had at least one dental anomaly. This preliminary study showed an association between a genetic variant at, or upstream of codon 1309, and radiographic dental anomalies.

Should Lecture Recordings Be Mandated in Dental Schools? Two Viewpoints: Viewpoint 1: Lecture Recordings Should Be Mandatory in U.S. Dental Schools and Viewpoint 2: Lecture Recordings Should Not Be Mandatory in U.S. Dental Schools.

Transcription or recording of lectures has been in use for many years, and with the availability of high-fidelity recording, the practice is now ubiquitous in higher education. Since technology has permeated education and today's tech-savvy students have expectations for on-demand learning, dental schools are motivated to record lectures, albeit with positive and negative implications. This Point/Counterpoint article addresses the question of whether lecture recording should be mandatory in U.S. dental schools. Viewpoint 1 supports the statement that lecture recording should be mandatory. Proponents of this viewpoint argue that the benefits-notably, student satisfaction and potential for improvement in student performance-outweigh concerns. Viewpoint 2 takes the opposite position, arguing that lecture recording decreases students' classroom attendance and adversely affects the morale of educators. Additional arguments against mandatory lecture recordings involve the expense of incorporating technology that requires ongoing support.

Identification and molecular characterization of 48 kDa calcium binding protein as calreticulin from finger millet (Eleusine coracana) using peptide mass fingerprinting and transcript profiling.

BACKGROUND: Attempts were made to identify and characterize the calcium binding proteins (CaBPs) in grain filling stages of finger millet using proteomics, bioinformatics and molecular approaches. RESULTS: A distinctly observed blue color band of 48 kDa stained by Stains-all was eluted and analyzed as calreticulin (CRT) using nano liquid chromatography-tandem mass spectrometry (nano LC-MS). Based on the top hits of peptide mass fingerprinting results, conserved primers were designed for isolation of the CRT gene from finger millet using calreticulin sequences of different cereals. The deduced nucleotide sequence analysis of 600 bp amplicon showed up to 91% similarity with CRT gene(s) of rice and other plant species and designated as EcCRT1. Transcript profiling of EcCRT1 showed different levels of relative expression at different stages of developing spikes. The higher expression of EcCRT1 transcripts and protein were observed in later stages of developing spikes which might be due to greater translational synthesis of EcCRT1 protein during seed maturation in finger millet. CONCLUSIONS: Preferentially higher synthesis of this CaBP during later stages of grain filling may be responsible for the sequestration of calcium in endoplasmic reticulum of finger millet grains.

Physicochemical and antioxidant properties of kiwifruit as a function of cultivar and fruit harvested month

The present study was carried out to find the effect of fruit harvesting stage (October, November and December) on the physicochemical and antioxidant properties in five kiwi cultivars (Abbot, Bruno, Allison, Hayward, Monty). Results showed that soluble solid content (SSC) and pH increased while ascorbic acid (Vit C), titrated acidity (TAD) and SSC/TAD decreased in all the cultivars with delay in harvesting. Total polyphenols (TP) were decreased while total flavonoids (TF) increased in all tested cultivars with delay in harvesting. The highest concentration of TP (2.02 mg gallic acid equivalent/g fresh weight) and TF (51.12 mg catechin equivalent/100g FW) were found in cultivar 'Allison' in the month of October and December, respectively. Antioxidant activities (AA) were genotype depended and no trend was observed with month of harvesting. Principal component analysis (PCA) showed strong correlation between Vit C, TP and antioxidant activities. Two major clusters were computed using agglomerative hierarchical clustering (AHC). All the studied important traits may be used in the breeding programmes to increase the variability for different physiochemical and antioxidative characteristics and to make suitable selections that could be acceptable to consumers.

A case-based and team-based learning model in oral and maxillofacial radiology.

The purpose of this article is to describe the process of transitioning a traditional face-to-face oral and maxillofacial radiology (OMR) lecture course to a case-based, team-based learning model for students ready to enter their fourth and final year of dental school. Data were collected from 294 new fourth-year students (Classes of 2009, 2010, and 2011) who participated in the newly formatted OMR course. At the time the course was taken, students had completed one year of clinical experience in taking and evaluating radiographic images on patients with various clinical conditions. Each class of approximately 100 students was divided into ten teams of ten each, and a topic on oral and maxillofacial lesions was assigned to each team. The teams researched their assigned topics, created PowerPoint presentations, and posted them on the course management system Blackboard site. The instructor posted on Blackboard eight to ten cases representing various lesions on that topic. Minimal clinical history was released at that point. Students reviewed the teams' PowerPoint presentations and the cases, answered the questions for each case, and turned in written assignments to be graded. The diagnoses were discussed in class. An end-of-course survey found that 71 percent of the students felt the case-based instruction helped them learn the content in a more comprehensive manner and 77 percent felt the in-class discussion increased their knowledge of radiographic interpretation. Some students said they felt uncomfortable being called on randomly during the class discussion. National Board Dental Examination results for the classes of 2009 and 2010 showed slight improvement when compared to national scores. As a result of student feedback, the course continues to be offered in the case-based, team-based format.

Comparison between cone-beam computed tomography and intraoral digital radiography for assessment of tooth root lesions.

INTRODUCTION: Cone-beam computed tomography (CBCT) might be more accurate in identifying radicular surface lesions compared with digital periapical radiography. In this study, we compared these techniques in detecting simulated root resorption lesions. METHODS: A porcine mandible was used to support 10 human maxillary central incisors. CBCT and digital periapical radiographic images were generated before and after the introduction of standardized and sequentially larger root defects on either the mesial or the lingual root surfaces. The images were randomly labeled and evaluated by 3 examiners. Each image was classified according to defect size (0, none; 1, mild; 2, moderate; 3, severe). RESULTS: Interrater reliability was acceptable (0.856 ≤ P ≤ 0.981). The location of the root defect (mesial vs lingual) had no significant effect on the evaluation of defect size. Both periapical radiographs and CBCT were slightly better at detecting lingual defects than mesial defects (75% vs 65% and 65% vs 60%, respectively), but these effects were not statistically significant (P = 0.49 and P = 0.74, respectively). The mean percentages of correctly diagnosed defect sizes were 65% for CBCT and 75% for periapical radiographs. Examiners using CBCT images tended to overestimate defect sizes (κ = 0.481) and correctly categorized teeth with no, mild-moderate, and severe defects 80%, 45%, and 90% of the time, respectively. Examiners using periapical radiographs tended to underestimate defect sizes (κ = 0.636) and categorized teeth with no, mild-moderate, and severe defects 100%, 50%, and 100% of the time, respectively. CONCLUSIONS: There was no difference in accuracy of identifying defects between periapical radiographs and CBCT images.

Efficacy of cone-beam computed tomography as a modality to accurately identify the presence of second mesiobuccal canals in maxillary first and second molars: a pilot study.

INTRODUCTION: The achievement of successful nonsurgical endodontic therapy relies on the location, disinfection, and obturation of all canals in the root canal system. This study evaluated the ability of the i-CAT cone-beam computed tomography (CBCT) unit (Imaging Sciences International, Hatfield, PA) to accurately identify the presence or absence of the second mesiobuccal canal (MB2) in maxillary first and maxillary second human molars. METHODS: Twenty completely intact maxillary first and second molars were used as test subjects. The existence of the MB2 canal was evaluated by the following three methods: (1) periapical radiograph evaluation, (2) CBCT evaluation, and (3) clinical sectioning evaluation. The evaluation methods were used to compare the accuracy of CBCT scanning and clinical sectioning (gold standard) in the identification of the MB2 canal. RESULTS: The i-CAT CBCT unit accurately identified the presence or absence of the MB2 canal in 78.95% of samples. Statistical analysis showed that there was no significant difference in the ability of CBCT scanning to detect the MB2 canal when compared with the gold standard of clinical sectioning (p > 0.5). CONCLUSION: The results of this in vitro investigation may be interpreted to show that CBCT scanning is a reliable method to detect the MB2 canal when compared with the gold standard of physical sectioning of the specimen.

In vivo comparison of conventional and cone beam CT synthesized cephalograms.

OBJECTIVE: To compare measurements from synthesized cone-beam computed tomography (CBCT) lateral cephalograms using orthogonal and perspective projections with those from conventional cephalometric radiographs. MATERIALS AND METHODS: Thirty-one patients were imaged using CBCT and conventional cephalometry. CBCT volume data were imported in Dolphin 3D. Orthogonal and perspective lateral cephalometric radiographs were created from three-dimensional (3D) virtual models. Twelve linear and five angular measurements were made on synthesized and conventional cephalograms in a randomized fashion. Conventional image measurements were corrected for known magnification. Linear and angular measurements were compared between image modalities using repeated measures analysis of variance. Statistical significance was defined as an alpha level of .01. RESULTS: With the exception of the Frankfort-mandibular plane angle (P < .0001), angular measurements were not statistically different for any modality (P > .01). Linear measurements, whether based on soft or hard tissue landmarks, were not statistically different (P > .01). CONCLUSIONS: Measurements from in vivo CBCT synthesized cephalograms are similar to those based on conventional radiographic images. Thus, additional conventional imaging may generally be avoided when CBCT scans are acquired for orthodontic diagnosis.

Bisphosphonate-related osteonecrosis of the jaws: a report of three cases demonstrating variability in outcomes and morbidity.

BACKGROUND: Bisphosphonates are used widely to manage skeletal disorders resulting from malignancies that destroy bone and from some metabolic bone diseases. A strong association between bisphosphonate treatment and the appearance of painful exposed nonvital bone in the mandible and maxilla after oral surgery has been reported in the last decade. Extensive reviews have appeared in the dental literature regarding bisphosphonate-related osteonecrosis of the jaws (BRONJ), including protocols for diagnosis, management and diagnostic imaging for early detection; feature definition; and determination of extent of the disease. CASE DESCRIPTION: The authors provide three case reports to show the contrast in treatment outcomes and morbidity in patients with BRONJ. The cases involved diagnostic imaging modalities commonly used in the practice of dentistry: panoramic radiography and cone-beam volumetric computed tomography. CLINICAL IMPLICATIONS: These case reports demonstrate the usefulness of dental diagnostic imaging in the detection and management of BRONJ, corroborate the increasing number of reports regarding high levels of morbidity associated with various BRONJ treatments, and underscore the danger of performing invasive dental procedures for patients receiving bisphosphonate therapy.