Functional Biomimetic Dental Restoration

Bioinspired functionally graded approach is an innovative material technology, which has rapidly progressed both in terms of materials processing and computational modeling in recent years. Bioinspired functionally graded structure allows the integration of dissimilar materials without formation of severe internal stress and combines diverse properties into a single material system. It is a remarkable example of nature’s ability to engineer functionally graded dental prostheses. Therefore, this novel technology is designed to improve the performance of the materials in medical and dental fields. Thus, this chapter book reviews the current status of the functionally graded dental prostheses and biomimetic process inspired by the human bone, enamel and dentin-enamel junction (DEJ) structures and the linear gradation in Young’s modulus of the human bone, enamel and dentin-enamel junction, as a new material design approach, to improve the performance compared to traditional dental prostheses. Notable research is highlighted regarding application of biomimetic prostheses into various fields in dentistry. The current chapter book will open a new avenue for recent researches aimed at the further development of new dental prostheses for improving their clinical durability

Niveles de percepción y confianza entre estudiantes de odontología y pasantes en la realización de diversos procedimientos de endodoncia.

Aim: The present study aimed to collect information from senior students and new interns enrolled at the College of Dentistry, University of Science and Technology (UST), regarding their confidence levels in performing endodontic treatments. Materials and Methods: Anonymous surveys were distributed to 40 senior students and 37 new interns at UST, in Sana'a, Yemen. They were asked to indicate their self-confidence level using a Likert scoring system ranging from 1 and 5. Mann-Whitney U test and chi-squared test were used to determine statistical significance between the studied groups. Results: 37.5% of students and 35.1% of interns rated endodontic practice as difficult. Only 55% of students found that the number of treated cases were satisfactory, similar to that reported by interns (56.8%). There were no statistically significant differences between both groups regarding self-confidence levels for most endodontic procedures (p<0.05). Placing of a rubber dam, followed by managing inter-appointment flare-ups were procedures in which both groups reported the lowest confidence. On the other hand, both groups felt the lowest confidence in the treatment of maxillary followed by mandibular molars. Statistically significant differences were reported between the two groups for performing root canal treatments (RCT) (p< 0.05). Self-confidence levels on the management of most different indications showed no statistically significant differences between both groups (p>0.05) with exception to the management of irreversible pulpitis, necrotic pulp, asymptomatic apical periodontitis, chronic abscess, and traumatic cases, in which significant differences were noticed (p<0.05). Immature apices, root resorption, endodontic-periodontal (EP) lesions, trauma, symptomatic apical periodontitis and acute abscess were ranked as the cases in which both groups reported the lowest confidence. Canal blockage and ledge formation were the main mishaps encountered during practice among students and interns. Conclusion: Students and interns displayed neutral confidence in performing endodontic treatments.Objetivo: El presente estudio tuvo como objetivo recopilar información de estudiantes de último año y nuevos pasantes inscritos en la Facultad de Odontología, Universidad de Ciencia y Tecnología (UST), con respecto a sus niveles de confianza en la realización de tratamientos de endodoncia. Materiales y métodos: se distribuyeron encuestas anónimas a 40 estudiantes de último año y 37 nuevos pasantes en UST, en Sana'a, Yemen. Se les pidió que indicaran su nivel de confianza en sí mismos utilizando un sistema de puntuación Likert que oscilaba entre 1 y 5. Se utilizaron la prueba U de Mann-Whitney y la prueba de ji al cuadrado para determinar la significación estadística entre los grupos estudiados. Resultados: el 37.5% de los estudiantes y el 35.1% de los pasantes calificaron la práctica de endodoncia como difícil. Solo el 55% de los estudiantes encontró que el número de casos tratados fue satisfactorio, similar al reportado por los pasantes (56.8%). No hubo diferencias estadísticamente significativas entre ambos grupos con respecto a los niveles de autoconfianza para la mayoría de los procedimientos de endodoncia (p<0.05). La colocación de una presa de goma, seguida de la gestión de brotes entre citas, fueron procedimientos en los que ambos grupos informaron la menor confianza. Por otro lado, ambos grupos sintieron la menor confianza en el tratamiento del maxilar seguido de los molares mandibulares. Se informaron diferencias estadísticamente significativas entre los dos grupos para realizar tratamientos de conducto radicular (ECA) (p<0.05). Los niveles de autoconfianza en el manejo de la mayoría de las indicaciones diferentes no mostraron diferencias estadísticamente significativas entre ambos grupos (p>0.05) con excepción del manejo de pulpitis irreversible, pulpa necrótica, periodontitis apical asintomática, absceso crónico y casos traumáticos, en los cuales se notaron diferencias (p<0.05). Los ápices inmaduros, la reabsorción radicular, las lesiones endodóncicas-periodontales (EP), los traumatismos, la periodontitis apical sintomática y el absceso agudo se clasificaron como los casos en que ambos grupos informaron la menor confianza. El bloqueo del canal y la formación de repisas fueron los principales percances encontrados durante la práctica entre estudiantes y pasantes. Conclusión: los estudiantes y los pasantes mostraron una confianza neutral en la realización de tratamientos de endodoncia

Diagnostic Value of Serum Neuron-Specific Enolase Level in Patients With Acute Ischemic Stroke; A Systematic Review and Meta-Analysis

Background: We aim to assess the predictive value of serum neuron-specific enolase (NSE) level in patients with acute ischemic stroke referring to the emergency department.Methods: This systematic review and meta-analysis performed, considering the PRISMA and MOOSE statement guidelines. A computerized literature search of the known medical database conducted by using the relevant keywords. We included studies published before November 2016 in which stroke patients compared with non-stroke controls and also studies evaluating the serum levels of NSE in the study groups. Statistical analysis was pooled in a random effect model analysis using the Comprehensive Meta-Analysis software.Results: We included 12 articles in the qualitative and quantitative analysis, that their quality acceptable based on the Newcastle Ottawa Scale (NOS scale). The pooled effect estimates showed that NSE is significantly higher in ischemic stroke patients in comparison with their controls with a high effect estimate [OR 9.68, 95% CI (3.06 to 30.6)]. The effect estimate remained statistically significant under the fixed and random effects model.Conclusion: Our results show higher levels of NSE in patients with stroke than in the control group, indicating that NSE plays a role in the diagnosis of stroke. In terms of prognosis, there is evidence regarding the direct and indirect relationship; and it founded that serum levels of NSE is higher in larger stroke volume, which needs further research

Prevalence of cesarean section on demand in Assiut Governorate, Egypt

Background: The current study aims to evaluate the prevalence of CS on demand in Women's health hospital, Assiut University and Abnob Central Hospital in Assiut Governorate, Egypt.Methods: A cross sectional study conducted in Assiut Women Health Hospital and Abnob central hospital from January 2017 to December 2017. The total number of cesarean section done was 180 cases and the number of CS on demand was 64 (35.6%). The demographic data were collected by one of the study investigators. Women were asked about the causes of requesting CS before surgery.Results: The study group was 64 women with age ranging from 18-40 years old, 40 primipara and 24 multipara. Of those 24 women, 21 of them previously delivered vaginally and only 3 women delivered by emergency CS. Twenty- six women had a history of previous abortion. Fear of pain was the main cause for CS on demand in the whole study participants (57.8%). In primipara, the main cause for requesting CS is fear of pain in 62.5% of participants followed by fear on the baby in 45 % of women. On the other hand, in multipara, the main cause for CS on demand was bad history of previous experience (60%) followed by fear of pain in 50% of cases. There was statistical significant difference between both groups in only two causes; fear of pelvic floor injuries (50% in multipara vs. 20% in primipara, p=0.02) and bad history of previous experience (60% in multipara vs. 0% in primipara, p=0.001). Other causes were not statistically different.Conclusions: The incidence of cesarean sections performed on request without medical indications is rising. The reasons for this are not only for perceived medical benefit, but also due to social, cultural, and psychological factors

Tensile stress distribution in maxillary central incisors restored with cast-made and prefabricated dental posts.

Abstract: Aim: To analyze and compare the tensile stress distribution in endodontically treated teeth restored with cast-made (Ni-Cr and gold) and prefabricated (titanium and glass fibre) dental posts. Methodology: Four three-dimensional finite element (FE) models of a maxillary central incisor restored with Ni-Cr cast-made (Model Ni-Cr), gold cast-made (Model GO), prefabricated titanium (Model TI) and prefabricated glass fibre (Model FP) posts were constructed. An oblique loading of 100N was applied to each three-dimensional model. Tensile stress distribution within the root dentine and at the post and surrounding structure interfaces were analysed. Results: In all the FE models studied, a higher magnitude of tensile stresses was observed on the palatal aspect of the cervical dentin as compared to the labial aspect and progressively decreases from the outer to the inner part of the root. The gold cast-made and glass fibre post models showed significantly less tensile stress concentration in the post-core component than the other experimental models. The maximum tensile stress was seen on the palatal aspect of the Ni-Cr compared to other posts. The higher magnitude interfacial tensile stress concentration was observed in a pulpless tooth restored with a Ni-Cr cast-made post, followed by titanium and gold cast-made posts, respectively. However, the minimum interfacial tensile stress was noticed in a pulpless tooth restored with a glass fibre post. Conclusion: Glass fibre posts tend to transfer tensile stress more homogenously within the tooth and at interfaces than the other types of investigated posts

Impact Of Breast Feeding Versus Formula Feeding On Surgical Wound Healing In Infants During The First Three Months Of Age

Breast milk has antimicrobial and healing properties that actually can help the wound healing. Surgical infants are at a much higher risk for malnutrition as a result of increased metabolic demands from surgery, nutrient losses, and sepsis. Many methods of feeding are used postoperatively for infants; oral feeding (breast or formula milk), enteral, or parenteral feeding. Aim of this work was to assess the effect of breast-feeding versus formula feeding on surgical wound healing in infant during the first three months. Methods and materials: Comparative descriptive research design was used to carry out this study. It comprised 100 infants aged less than 3 months, they were divided into two equal groups as the following: Group 1: received breast milk feeding, Group 2: received formula milk feeding. Tools were developed by the researcher, after that the researcher fulfill assessment sheet and took anthropometric measurements for each infant then the photographs were taken by the researcher on the 7th postoperative day and reassessed for second time on the 14th day. Results: Out of the included breast-fed infants, 78 % were boys, while 22% were girls

Double negative alpha beta T cells in pediatric hemophagocytic syndromes

Introduction: Autoimmune lymphoproliferative syndrome (ALPS) and hemophagocytic lymphohistiocytosis (HLH) share clinical and laboratory features including lymphadenopathy, splenomegaly, and pancytopenia. We sought to measure αβ double negative T cells (αβ DNT) in a group of patients with established diagnosis of HLH in relation to disease activity and severity.Methods: We conducted a follow-up, controlled study that comprised 25 patients with HLH and 25 healthy matched controls. Patients were subjected to clinical evaluation and flowcytometric measurement of αβ DNT Cells at presentation and 9 weeks after start of HLH induction treatment.Results: In 17 (68%) patients, infection was the trigger of HLH while the cause was malignancy in three (12%), and rheumatological disorders in two patients (8%). At enrollment, 15 patients (60%) had αβ DNT cells levels [median (IQR): 1.71 (1.25-2.12)] that were significantly higher than the control values [median (IQR): 0.7 (0.4-0.8)] (p<0.001). The αβ DNT counts of patients were also higher at enrollment as compared to values at the end of week 9 [median (IQR): 0.76 (0.45-1.17)]; p=0.018. Survivors (n=8) and non-survivors (n=17) had comparable levels of αβ DNT cells at enrollment (p=0.861). αβ DNT cell count correlated positively with ALT (p=0.019) and negatively with CD4/CD8 ratios (p=0.023).Conclusion: Elevated αβ DNT cell counts might be related to the HLH process and this implies that mild elevation can exist in HLH and are not specific to ALPS. Wider scale studies with longer periods of follow up are needed to validate the results and properly outline the correlation between both medical conditions.Keywords: Hemophagocytic lymphohistiocytosis, Double negative T cells, mortality, ALP

Towards Developing Mid-Infrared Photonics Using Mxenes

Recent research and development in the mid-infrared (IR) wavelength range (2-20 um) for a variety of applications, such as trace gas monitoring, thermal imaging, and free space communications have shown tremendous and fascinating progress. MXenes, which mainly refer to two-dimensional (2D) transition-metal carbides, nitrides, and carbonitrides, have drawn a lot of interest since their first investigation in 2011. MXenes project enormous potential for use in optoelectronics, photonics, catalysis, and energy harvesting fields proven by extensive experimental and theoretical studies over a decade. MXenes offers a novel 2D nano platform for cutting-edge optoelectronics devices due to their interesting mechanical, optical, and electrical capabilities, along with their elemental and chemical composition. We here discuss the key developments of MXene emphasizing the evolution of material synthesis methods over time and the resulting device applications. Photonic and optoelectronic device design and fabrication for mid-IR photonics are demonstrated by integrating MXene materials with various electrical and photonic platforms. Here, we show the potential of using Mxene in photonics for mid-IR applications and a pathway toward achieving next-generation devices for various applications.Comment: 50 Pages, 21 figure

Evaluación de la prescripción y uso de medicamentos supresores de ácido en hospitales centrales en la región de Abha, Arabia Saudita

Objective: The aim of this study was to study and assess the indications of acid suppressive drugs and to find out percentage of irrational prescriptions with acid suppressive drugs. Material/Methods: It is a prospective observational study conducted in the Armed Forces Hospitals Southern Region and Abha Maternity Hospital, both in Abha in Assir region (Saudi Arabia). The sample size of study was 185 patients. The case sheets of the patients’ prescription order were reviewed for acid suppressive drugs prescription and relevant data was taken. Patients’ age above 18 were identified. The duration of study was 8 weeks, between May and June 2017. Results: Our results showed that the majority of the prescriptions of proton pump inhibitors (68.1%) were unjustifiable and that proton pump inhibitor was the most commonly prescribed acid suppressive drugs for the patients (97.8%). The frequency of prescribing for the autism spectrum disorders in our study was found to be higher in patients with an existing risk factor and was mostly recommended by physicians as concomitant medications (67.6%). The most common concomitant medications used with the proton pump inhibitors were non-steroidal anti-inflammatory drugs (29.2%) in which aspirin composed 13.5% of the non-steroidal anti-inflammatory drugs prescribed followed by antimicrobials (9.2%). Conclusion: Acid suppressive drugs are the most commonly prescribed drugs with no proper indications hence irrational. Based on the results of this study, creating awareness about reasonable use of acid suppressive drugs is a necessity.Objetivo: El objetivo de este estudio fue estudiar y evaluar las indicaciones de los medicamentos supresores de ácidos y averiguar el porcentaje de recetas irracionales con medicamentos supresores de ácidos. Material / Métodos: es un estudio observacional prospectivo realizado en los Hospitales de las Fuerzas Armadas del Sur y en el Hospital de Maternidad Abha, ambos en Abha en la región de Assir (Arabia Saudita). El tamaño muestral del estudio fue de 185 pacientes. Se revisaron las hojas de casos de orden de prescripción de los pacientes para la prescripción de medicamentos supresores de ácido y se tomaron los datos pertinentes. Se identificó la edad de los pacientes mayores de 18 años. La duración del estudio fue de 8 semanas, entre mayo y junio de 2017. Resultados: nuestros resultados mostraron que la mayoría de las prescripciones de inhibidores de la bomba de protones (68,1%) eran injustificables y que este era el fármaco supresor de ácido más comúnmente prescrito para los pacientes (97,8%). La frecuencia de prescripción para los trastornos del espectro autistas en nuestro estudio, fue mayor en pacientes con un factor de riesgo existente y fue recomendada principalmente por los médicos como medicamentos concomitantes (67,6%). Los medicamentos concomitantes más comunes que se usaron con los inhibidores de la bomba de protones fueron los antiinflamatorios no esteroideos (29.2%) en los cuales la aspirina supuso el 13,5% de los antiinflamatorios no esteroideos prescritos, seguidos por los antimicrobianos (9.2%) Conclusión: los medicamentos supresores de ácido son los medicamentos más comúnmente recetados sin indicaciones adecuadas, por lo que son irracionales. Basado en los resultados de este estudio, crear conciencia sobre el uso razonable de los medicamentos supresores del ácido es una necesidad

Meroterpenoids: A Comprehensive Update Insight on Structural Diversity and Biology.

Funder: This research was funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University through the Fast-track Research Funding ProgramMeroterpenoids are secondary metabolites formed due to mixed biosynthetic pathways which are produced in part from a terpenoid co-substrate. These mixed biosynthetically hybrid compounds are widely produced by bacteria, algae, plants, and animals. Notably amazing chemical diversity is generated among meroterpenoids via a combination of terpenoid scaffolds with polyketides, alkaloids, phenols, and amino acids. This review deals with the isolation, chemical diversity, and biological effects of 452 new meroterpenoids reported from natural sources from January 2016 to December 2020. Most of the meroterpenoids possess antimicrobial, cytotoxic, antioxidant, anti-inflammatory, antiviral, enzyme inhibitory, and immunosupressive effects