Network Analysis and Natural Language Processing to Obtain a Landscape of the Scientific Literature on Materials Applications.

Recent progress in natural language processing (NLP) enables mining the literature in various tasks akin to knowledge discovery. Obtaining an updated birds-eye view of key research topics and their evolution in a vast, dynamic field such as materials science is challenging even for experienced researchers. In this Perspective paper, we present a landscape of the area of applied materials in selected representative journals based on a combination of methods from network science and simple NLP strategies. We found a predominance of energy-related materials, e.g., for batteries and catalysis, organic electronics, which include flexible sensors and flexible electronics, and nanomedicine with various topics of materials used in diagnosis and therapy. As for the impact calculated through standard metrics of impact factor, energy-related materials and organic electronics are again top of the list across different journals, while work in nanomedicine has been found to have a lower impact in the journals analyzed. The adequacy of the approach to identify key research topics in materials applications was verified indirectly by comparing the topics identified in journals with diverse scopes, including journals that are not specific to materials. The approach can be employed to obtain a fast overview of a given field from the papers published in related scientific journals, which can be adapted or extended to any research area.

A complex network approach to political analysis: Application to the Brazilian Chamber of Deputies.

In this paper, we introduce a network-based methodology to study how political entities evolve over time. We constructed networks of voting data from the Brazilian Chamber of Deputies, where deputies are nodes and edges are represented by voting similarity among deputies. The Brazilian Chamber of deputies is characterized by a multi-party political system. Thus, we would expect a broad spectrum of ideas to be represented. Our results, however, revealed that plurality of ideas is not present at all: the effective number of communities representing ideas based on agreement/disagreement in propositions is about 3 over the entire studied time span. The obtained results also revealed different patterns of coalitions between distinct parties. Finally, we also found signs of early party isolation before presidential impeachment proceedings effectively started. We believe that the proposed framework could be used to complement the study of political dynamics and even applied in similar social networks where individuals are organized in a complex manner.

Detection of Fractured Endodontic Instruments in Root Canals: Comparison between Different Digital Radiography Systems and Cone-beam Computed Tomography.

INTRODUCTION: This study compared the detection of fractured instruments in root canals with and without filling by periapical radiographs from 3 digital systems and cone-beam computed tomographic (CBCT) images with different resolutions. METHODS: Thirty-one human molars (80 canals) were used. Root canals were divided into the following groups: the control group, without fillings; the fracture group, without fillings and with fractured files; the fill group, filled; and the fill/fracture group, filled and with fractured files. Digital radiographs in ortho-, mesio-, and distoradial directions were performed in 2 semidirect systems (VistaScan [Dürr Dental, Beitigheim-Bissinger, Germany] and Express [Instrumentarium Imaging, Tuusula, Finland]) and a direct system (SnapShot [Instrumentarium Imaging]). CBCT images were acquired with 0.085-mm and 0.2-mm voxel sizes. All images were assessed and reassessed by 4 observers for the presence or absence of fractured files on a 5-point scale. The sensitivity, specificity, and accuracy were calculated. RESULTS: In the absence of filling, accuracy values were high, and there were no statistical differences among the radiographic techniques, different digital systems, or the different CBCT voxels sizes. In the presence of filling, the accuracy of periapical radiographs was significantly higher than CBCT images. In general, SnapShot showed higher accuracy than VistaScan and Express. CONCLUSIONS: Periapical radiographs in 1 incidence were accurate for the detection of fractured endodontic instruments inside the root canal in the absence or presence of filling, suggesting that this technique should be the first choice as well as the direct digital radiographic system. In the presence of filling, the decision to perform a CBCT examination must take into consideration its low accuracy.

Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal.

PURPOSE: The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. MATERIALS AND METHODS: Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. RESULTS: In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. CONCLUSION: CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region.

Erratum to: Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal.

[This corrects the article on p. 159 in vol. 46, PMID: 27672611.].

Prevalence of suggestive images of carotid artery calcifications on panoramic radiographs and its relationship with predisposing factors.

Panoramic radiographs (PR) can display radiopaque images suggestive of calcified atheroma in the carotid artery in asymptomatic patients. The aim of this study was to evaluate the prevalence of these images on PR and their linkage with hypertension, obesity, age, gender and smoking habits. PR of 505 patients were evaluated. They were older than 30 years old and their PR had been taken for different clinical reasons. Their body mass index was calculated; their waist circumference was also taken into consideration. Information about smoking habits and hypertension was obtained. The observers analyzed the presence of radiopaque mass in the region of the cervical vertebrae C3-C4 through the PR, confirmed by an antero-posterior (AP) radiograph. The results showed a 7.92% prevalence of suggestive images of calcifications on PR and on AP radiograph. The adjusted Odds Ratio showed association with age and smoking habits. The calcification process is almost nine times higher for the elderly when compared to the young. As far as smokers are concerned, this process is twice worse when compared to no smokers. In conclusion, 7.92% of the group studied presented suggestive images of carotid atherosclerosis on PR, which is directly associated with the age and smoking habits.

Can the Incorporation of a Lead Foil on the Backside of Digital Receptors Produce a Better Endodontic Diagnosis? / ¿Puede la Incorporación de una Lámina de Plomo en la Parte Posterior de los Receptores Digitales Producir un Mejor Diagnóstico Endodóntico?

This study evaluated influence of addition of lead foil coupled to different types of digital receptors on image noise and on diagnosis of fractured instruments in teeth without and with root filling. Twenty-six molars had their root canals (n=67) cleaned and shaped and were divided into groups with and without root filling and with and without fractured instruments. Images were acquired in PSP and CMOS sensor, with and without addition of a lead foil coupled to the digital receptors. Diagnostic values were obtained by the area under the ROC curve, and one-way ANOVA compared the groups. Noise in images was measured by the standard deviation of mean gray values in images with and without the lead foil, and compared by two-way ANOVA (a=0.05). Addition of lead foil did not interfere in the diagnostic accuracy for both digital systems (p>0.05) and did not decrease noise in the images (p>0.05). However, independently of the addition of the lead foil, the phosphor-storage plate presented higher noise compared to the sensor (p ?0.05). Addition of lead foil to the digital receptor did not interfere in image noise and with the diagnostic accuracy for detecting fracured endodontic instrument in ex-vivo conditions.

Este estudio evaluó la influencia de láminas de plomo acopladas a diferentes tipos de receptores digitales sobre el ruido de la imagen y el diagnóstico de instrumentos fracturados en dientes sin y con obturación radicular. Se limpiaron y moldearon 26 molares (n = 67), se dividieron en grupos con y sin relleno radicular y con y sin instrumentos fracturados. Las imágenes se adquirieron en el sensor PSP y CMOS, con y sin adición de una lámina de plomo acoplada a los receptores digitales. Los valores diagnósticos se obtuvieron por el área bajo la curva ROC y con ANOVA de una vía comparó los grupos. El ruido en las imágenes se midió mediante la desviación estándar de los valores medios de gris en las imágenes con y sin la lámina de plomo, y se comparó mediante ANOVA bidireccional (a = 0,05). La adición de lámina de plomo no interfirió en la precisión diagnóstica de ambos sistemas digitales (p> 0,05) y no disminuyó el ruido en las imágenes (p> 0,05). Sin embargo, independientemente de la adición de la lámina de plomo, la placa de almacenamiento de fósforo presentó mayor ruido en comparación con el sensor (p?0,05). La adición de lámina de plomo al receptor digital no interfirió con el ruido de la imagen y con la precisión diagnóstica para detectar el instrumento endodóntico fracturado en condiciones ex vivo.

Bisphosphonate-related osteonecrosis of the jaw: a review of the literature.

Bisphosphonates (BPs) are a class of drugs used to treat osteoporosis and malignant bone metastasis. BPs show high binding capacity to the bone matrix, especially in sites of active bone metabolism. The American Society for Bone and Mineral Research defines BRONJ as "an area of exposed bone in the maxillofacial region that has not healed within 8 weeks after identification by a healthcare provider in a patient who is receiving or has been exposed to a bisphosphonate and has not had radiation therapy to the craniofacial region." Bisphosphonate-related osteonecrosis of the jaw (BRONJ) can adversely affect quality of life, as it may produce significant morbidity. The American Association of Oral and Maxillofacial Surgeons (AAOMS) considers as vitally important that information on BRONJ be disseminated to other dental and medical specialties. The purpose of this work is to offer a perspective on how dentists should manage patients on BPs, to show the benefits of accurately diagnosing BRONJ, and to present diagnostic aids and treatments strategies for the condition.

Prevalence of suggestive images of carotid artery calcifications on panoramic radiographs and its relationship with predisposing factors / Prevalência de imagens sugestivas de calcificações da artéria carótida em radiografias panorâmicas e sua relação com fatores predisponentes

Abstract Panoramic radiographs (PR) can display radiopaque images suggestive of calcified atheroma in the carotid artery in asymptomatic patients. The aim of this study was to evaluate the prevalence of these images on PR and their linkage with hypertension, obesity, age, gender and smoking habits. PR of 505 patients were evaluated. They were older than 30 years old and their PR had been taken for different clinical reasons. Their body mass index was calculated; their waist circumference was also taken into consideration. Information about smoking habits and hypertension was obtained. The observers analyzed the presence of radiopaque mass in the region of the cervical vertebrae C3-C4 through the PR, confirmed by an antero-posterior (AP) radiograph. The results showed a 7.92% prevalence of suggestive images of calcifications on PR and on AP radiograph. The adjusted Odds Ratio showed association with age and smoking habits. The calcification process is almost nine times higher for the elderly when compared to the young. As far as smokers are concerned, this process is twice worse when compared to no smokers. In conclusion, 7.92% of the group studied presented suggestive images of carotid atherosclerosis on PR, which is directly associated with the age and smoking habits.

Resumo As radiografias panorâmicas (RP) podem exibir imagens radiopacas sugestivas de ateromas calcificados na artéria carótida em pacientes assintomáticos. O objetivo deste estudo foi avaliar a prevalência destas imagens na RP e sua relação com hipertensão, obesidade, idade, sexo e tabagismo. Foram avaliadas RP de 505 pacientes acima de trinta anos, que realizaram esse exame por diversos motivos clínicos. Seu índice de massa corpórea foi calculado; sua circunferência abdominal também foi considerada. Informações sobre hipertensão e tabagismo foram obtidas. Os observadores avaliaram as RP para a presença de massas radiopacas na região das vértebras cervicais C3-C4, confirmadas por meio de uma radiografia ântero-posterior (AP). Os resultados mostraram prevalência de 7,92% de imagens sugestivas de calcificações em RP e na radiografia AP. A razão de probabilidade (OR) ajustada mostrou associação com idade e tabagismo. O risco para as pessoas mais velhas aumenta até cerca de nove vezes quando comparado com aqueles mais jovens, enquanto para os fumantes, o risco é o dobro, quando comparado com não fumantes. Na população estudada, 7,92% de todos os sujeitos apresentaram imagens sugestivas de aterosclerose carotídea em RP e houve associação com idade e tabagismo.

Microabrasão como tratamento de esmalte fluorótico / Microabrasion as treatment of enamel fluorosis

Atualmente há forte tendência internacional a opinião favorável sobre a importância da utilização do flúor como coadjuvante na redução dos índices de cárie, tanto em países desenvolvidos quanto subdesenvolvidos. Todavia, simultaneamente os índices de fluorose dental parecem crescer em proporção inversa. Esta ocorre como resultado da intoxicação crônica por flúor, ocasionada pela ingestão acima do limite adequado por um período de tempo prolongado. A microabrasão do esmalte é um método efetivo para remover descolorações superficiais que esta condição provoca no esmalte, afetando sua estética. A utilização de ácido clorídrico a 18% associado à pedra pomes apesar de ser simples e de baixo custo foi paulatinamente substituída devido ao ácido clorídrico ser de alto risco de causar alguns danos aos tecidos periodontais. Por este motivo, este trabalho mostra um caso clínico de tratamento de fluorose de esmalte resolvido com microabrasão, usando o ácido fosfórico. A ingestão deliberada de creme dental foi a provável causa das manchas. Devido à posição do dentes na arcada e à amplitude do sorriso do paciente, selecionaram-se apenas os seis dentes anteriores superiores para receberem o tratamento proposto. Quatro sessões, intervaladas por sete dias cada, foram executadas, utilizando-se pasta de pedra pomes e ácido fosfórico a 37%. Nas duas primeiras sessões, sob isolamento absoluto do campo operatório, friccionou-se a pasta sobre o esmalte com taça de borracha acionada por micromotor de baixa rotação, e nas regiões de difícil usou-se tiras de lixa. Nas duas últimas sessões, foram feitos apenas pequenos retoques, fricionando-se a pasta com espátula de madeira manualmente.

There is currently a trend in favor of using fluoride as a coadjuvant in reducing caries indexes, as much in underdeveloped as in developed countries. However, simultaneously the indexes of dental fluorosis seem to grow in an inverse proportion. This is brought about by chronic ingestion of fluoride for a prolonged length of time or in high concentration. Enamel microabrasion is an effective method to remove superficial stains caused by this condition, which affects esthetics of that tissue. The use of 18% hydrochloric acid in association with pumice, despite being a simple and low cost method, has been gradually replaced due to its potential of causing damage to periodontal tissues. Thus, this article reports the treatment of a fluorosis clinical case solved with microabrasion using phosphoric acid 37%, because its cost-benefit is supposedly better than with chloridric acid. The deliberate ingestion of toothpaste was the probable cause of the tooth stains. Due to the location of the teeth and to the patient's smile, only the six upper anterior teeth were selected to receive the proposed treatment. Four clinical sessions, with a seven days interval between each other, were carried out using 37% phosphoric acid and pumice. Under rubber dam isolation, the two first sessions consisted of rubbing the acid-pumice mix on enamel surface using a rubber cup on slow speed, and abrasive paper strips on the interproximal tooth surfaces. On the two final sessions, only finishing touches were performed using a wooden spatula to manually rub the acid-pumice paste.