Mechanical Properties of Dual-Cured Resin Luting Agents for Ceramic Restoration

Purpose: The aim of the present study was to evaluate the mechanical properties including surface hardness, flexural strength, and flexural modulus of two dual-cured resin luting agents (New Resin Cement [NRC] and Variolink II [VLII]) irradiated through four different thickness of leucite ceramics (0, 1, 2, and 3 mm) and their shear bond strength to zirconia ceramic (Cercon) using each ceramic primer. Materials and Methods: Knoop hardness was measured on a thin layer of resin luting agent on the ceramic surface. Three-point bending tests were performed after 24 h storage at 37°C. Two different-shaped zirconia ceramic specimens with or without sandblasting with alumina were treated with each primer. The specimens were then cemented together with each resin luting agent. Half of the specimens were stored in water at 37°C for 24 h and the other half were thermocycled 5,000 times. Results: VLII revealed statistically higher Knoop hardness and flexural modulus than NRC for each thickness of ceramic. No significant differences in flexural strength were observed between VLII and NRC for each ceramic spacer. Reduction of the mechanical properties with increase of ceramic thickness varied for each property. However, these properties were similar between the two materials. Blasting with alumina was significantly effective for increasing shear bond strength of both resin luting agents before and after thermal cycling. The use of New Ceramic Primer showed the highest shear bond strength and maintained bond durability after 5,000 thermocycles. Conclusion: Mechanical properties of NRC dual-cured resin luting agent appear adequate for ceramic restorations.This is an electronic version of an Article published in Journal of Prosthodontics 16(5): 370-376, 2007

Susceptibility and Response of Human Blood Monocyte Subsets to Primary Dengue Virus Infection

Human blood monocytes play a central role in dengue infections and form the majority of virus infected cells in the blood. Human blood monocytes are heterogeneous and divided into CD16− and CD16+ subsets. Monocyte subsets play distinct roles during disease, but it is not currently known if monocyte subsets differentially contribute to dengue protection and pathogenesis. Here, we compared the susceptibility and response of the human CD16− and CD16+ blood monocyte subsets to primary dengue virus in vitro. We found that both monocyte subsets were equally susceptible to dengue virus (DENV2 NGC), and capable of supporting the initial production of new infective virus particles. Both monocyte subsets produced anti-viral factors, including IFN-α, CXCL10 and TRAIL. However, CD16+ monocytes were the major producers of inflammatory cytokines and chemokines in response to dengue virus, including IL-1β, TNF-α, IL-6, CCL2, 3 and 4. The susceptibility of both monocyte subsets to infection was increased after IL-4 treatment, but this increase was more profound for the CD16+ monocyte subset, particularly at early time points after virus exposure. These findings reveal the differential role that monocyte subsets might play during dengue disease

Macrophage biology in development, homeostasis and disease

Macrophages the most plastic cells of the hematopoietic system are found in all tissues and exhibit great functional diversity. They have roles in development, homeostasis, tissue repair, and immunity. While anatomically distinct, resident tissue macrophages exhibit different transcriptional profiles, and functional capabilities, they are all required for the maintenance of homeostasis. However, these reparative and homeostatic functions can be subverted by chronic insults, resulting in a causal association of macrophages with disease states. In this review, we discuss how macrophages regulate normal physiology and development and provide several examples of their pathophysiologic roles in disease. We define the “hallmarks” of macrophages performing particular functions, taking into account novel insights into the diversity of their lineages, identity, and regulation. This diversity is essential to understand because macrophages have emerged as important therapeutic targets in many important human diseases

Testing a Cloud-Based Model for Active Surveillance of Medical Devices with Analyses of Coronary Stent Safety Using the Data Extraction and Longitudinal Trend Analysis (DELTA) System

Joseph P Drozda Jr,1,* Henry Ssemaganda,2,* Edward A Frankenberger,3,* Eric Brandt,4,* Susan Robbins,2,* Neha Khairnar,2,* Alexandra Cha,5,* Frederic S Resnic6,* 1Retiree, Mercy, Chesterfield, MO, USA; 2Comparative Effectiveness Research Institute, Lahey Hospital and Medical Center, Burlington, MA, USA; 3Freenome, South San Francisco, CA, USA; 4Research, Mercy, Chesterfield, MO, USA; 5Booz Allen Hamilton, Bethesda, MD, USA; 6Division of Cardiovascular Medicine, Lahey Hospital and Medical Center, Burlington, MA, USA*These authors contributed equally to this workCorrespondence: Joseph P Drozda Jr, Tel +1 314 308 1732, Email [email protected]: To demonstrate the use of the Data Extraction and Longitudinal Trend Analysis (DELTA) system in the National Evaluation System for health Technology’s (NEST) medical device surveillance cloud environment by analyzing coronary stent safety using real world clinical data and comparing results to clinical trial findings.Design and Setting: Electronic health record (EHR) data from two health systems, the Social Security Death Master File, and device databases were ingested into the NEST cloud, and safety analyses of two stents were performed using DELTA.Participants and Interventions: This is an observational study of patients receiving zotarolimus drug-eluting coronary stents (ZES) or everolimus eluting coronary stents (EES) between July 1, 2015 and December 31, 2017.Results: After exclusions, 3334 patients receiving EES and 1002 receiving ZES were available for study. Analysis using inverse probability weighting showed no significant difference in one-year mortality or major adverse cardiac events (MACE) for EES compared to ZES [Mortality Odds Ratio 0.94 (95% CI 0.81– 1.175); p = 0.780] [MACE Odds Ratio 1.04 (95% CI 0.92– 1.16; p = 0.551]). Analysis using propensity matching showed no significant difference in EES one-year mortality (547 of 992 alive and available after censoring) compared to ZES (546 of 992) [Log-Rank statistic 0.3348 (p = 0.563)].Conclusion: Automated cloud-based medical device safety surveillance using EHR data is feasible and was efficiently performed using DELTA. No statistically significant differences in 1-year safety outcomes between ZES and EES were identified using two statistical approaches, consistent with randomized trial findings.Plain Language Summary: What is already known on this topic–The National Evaluation System for health Technology (NEST) Coordinating Center has developed a prototype cloud-based medical device surveillance system designed to capture clinical data obtained during routine care along with automated analysis tools to monitor device safety and performance in a real-world setting. DELTA is a suite of open-source active surveillance software tools that has been successfully deployed in other data environments and was being evaluated in the NEST cloud.What this study adds–This paper reports on the validation of DELTA methods deployed in the NEST cloud environment (appendix) as well as the initial demonstration of active safety surveillance for two commonly used coronary stent devices. Electronic health record data on the two coronary stents from two health systems were ingested into the Cloud, linked to the Social Security Death Master File along with a reference device database, and analyzed with DELTA as a prototype of an active safety surveillance system.How this study might affect research, practice, or policy–Consistent with clinical trials and a prior independent analysis, no statistically significant differences in clinical outcomes were found between the two stents. Importantly, the results support the feasibility of using the NEST multi-health system cloud for monitoring medical device safety and effectiveness. The system could minimize the risks associated with late recognition of device safety issues and support assessments of medical device value in the real world.Keywords: active surveillance, safety-based medical device withdrawals, real-world evidence, cardiac devices, outcomes assessment (health care

Contemporary Dental Ceramics

Dental ceramics were increasingly introduced to restorative dentistry at the beginning of the XX century as porcelain jacket crowns. However, their limited use in clinical practice was mainly associated to the mechanical shortcomings. In the early sixties porcelain-fused to-metal restorations were developed and for years have represented the “gold standard”, thanks to their good mechanical properties and to somewhat satisfactory esthetics. In the last thirty years, the growing demand for highly esthetic restorations has led to development of new all-ceramic materials and techniques. All-ceramic restorations combine esthetic veneering porcelains (consisting of a glass and a crystalline phase of fluoroapatite, aluminum oxide, or leucite) with strong ceramic cores, mainly made of lithium-disilicate, aluminum-oxide or zirconium-oxide. The most common complication is fracture that can initiate from several different sites on the surface, at interfaces, or within the material. While conventional methods of ceramic fabrication usually contain internal porosity, CAD/CAM technology ensures almost no internal defects. Such improvements in ceramic processing have allowed better structural reliability and greatly contributed to the success of all-ceramic systems. The aim of this study was to provide an overview on development of ceramic systems used in dentistry, their processing, including computer-aided design and computer-aided (CAD/CAM) technology, applications and future perspectives in this field