277 results match your criteria curing distance

Predicting transmitted irradiance through CAD/CAM resin composite crowns in a simulated clinical model.

Dent Mater 2021 Apr 6. Epub 2021 Apr 6.

Department of Operative/Restorative Dentistry, Periodontology and Pedodontics, Ludwig-Maximilians University Munich, Goethestrasse 70, 80336 Munich, Germany. Electronic address:

Objective: To predict the clinically relevant transmitted irradiance that is available for luting when a CAD/CAM restoration is inserted. The influence of irradiance, exposure distance, light curing unit (LCU) angulation and direction of polymerization is analyzed when curing through crowns of different thicknesses.

Methods: Three modern CAD/CAM resin-based composites (RBCs) were used to produce 45 crown-shaped specimens. Read More

View Article and Full-Text PDF

Estimation of the tolerance threshold for the irradiance of modern LED curing units when simulating clinically relevant polymerization conditions.

Dent Mater J 2021 Mar 5. Epub 2021 Mar 5.

Department of Conservative Dentistry and Periodontology, University Hospital.

The study aims to characterize various LED light curing units (LED-LCU) in order to determine the tolerance threshold for varying the polymerization conditions. Two violet-blue and two blue LED-LCUs were analyzed by using a laboratory-grade spectrophotometer system. Fifty-five curing conditions were simulated in each LED-LCU by varying the position (centered and with an offset of 3-mm to the left, right, lower and upper direction) and the exposure distance (0 mm to 10 mm in 1-mm steps). Read More

View Article and Full-Text PDF

Construction of Nanocrystalline Cellulose-Based Composite Fiber Films with Excellent Porosity Performances via an Electrospinning Strategy.

ACS Omega 2021 Feb 11;6(7):4958-4967. Epub 2021 Feb 11.

State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, P. R. China.

Cellulose nanocrystals (CNCs) not only have environmental protection characteristics of being lightweight, degradable, green, and renewable but also have some nanocharacteristics of high strength, large specific surface area, and obvious small size effect, so they are often used as a reinforcing agent in various polymers. However, the hydrogen bonding between CNC molecules is relatively strong, and they can easily aggregate and get entangled with each other. In this work, several large-porosity composite nanofiber films, KH550-CNC/waterborne polyurethane (WPU)/poly(vinyl alcohol) (PVAL) with KH550-modified CNCs, are prepared using poly(vinyl alcohol) (PVAL) solution and electrospinning technology. Read More

View Article and Full-Text PDF
February 2021

Effects of curing lights on human gingival epithelial cell proliferation.

J Am Dent Assoc 2021 Apr 23;152(4):260-268. Epub 2021 Feb 23.

Background: Light-emitting diode (LED) and quartz-tungsten-halogen (QTH) curing lights are used commonly in clinics. The aim of this study was to assess the effect of these lights on the proliferation of human gingival epithelial cells.

Methods: Smulow-Glickman (S-G) cells were exposed to a VALO LED (Ultradent) or an XL3000 QTH (3M ESPE) light at 1 millimeter or 6 mm distance for 18, 39, 60, and 120 seconds. Read More

View Article and Full-Text PDF

Implementation of the Use of Ethnomedicinal Plants for Curing Diseases in the Indian Himalayas and Its Role in Sustainability of Livelihoods and Socioeconomic Development.

Int J Environ Res Public Health 2021 02 5;18(4). Epub 2021 Feb 5.

Ethnobotanical Society of Nepal, Kathmandu 44600 Nepal.

In recent times, the use of traditional herbal medicines in healthcare has declined, particularly amongst the rural population. This implies a risk of losing vital information from previous generations regarding plants and their use in traditional medicine. The objective of this study is to catalog the ways employed by inhabitants of the Garhwal Himalayas as part of their traditional approaches to healthcare. Read More

View Article and Full-Text PDF
February 2021

Are we curing by cutting? A call for long-term follow up and outcomes research in global surgery interventions - perspective.

Int J Surg 2021 Mar 26;87:105885. Epub 2021 Jan 26.

Department of Surgery, Plastic and Reconstructive Surgery Division, Stanford University School of Medicine, Stanford, CA, USA; ReSurge International, Sunnyvale, CA, USA.

Success in global surgery interventions cannot be claimed until consistent long-term follow up is achieved and corresponding outcomes are studied. However, post-operative outcomes remain inconsistently collected and analyzed in the setting of global surgery, with current efforts largely focused on the delivery of surgical care. Barriers in low- and middle-income countries include patient cost and distance, low surgical workforce capacity, poor patient health literacy, lack of affordable technology availability, inconsistent documentation, and structural deficiencies. Read More

View Article and Full-Text PDF

Correlation of the mechanical and biological response in light-cured RBCs to receiving a range of radiant exposures: Effect of violet light.

J Dent 2021 02 29;105:103568. Epub 2020 Dec 29.

Department of Dental Clinical Sciences, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada.

Objective: This study correlates the mechanical and biological response of commercially available resin-based composites (RBCs) to clinically relevant light-curing conditions.

Methods: Two RBCs (Venus and Venus Pearl; Kulzer) that use different monomer and photo-initiator systems, but have a similar filler volume and shade, were exposed to either just blue light, or violet and blue light from two different LCUs (Translux Wave and Translux 2Wave; Kulzer). Distance and exposure times were adjusted so that both LCUs delivered 5 similar levels of radiant exposures (RE) between 1. Read More

View Article and Full-Text PDF
February 2021

Cuspal Deflection and Temperature Rise of MOD Cavities Restored through the Bulk-Fill and Incremental Layering Techniques Using Flowable and Packable Bulk-Fill Composites.

Materials (Basel) 2020 Dec 11;13(24). Epub 2020 Dec 11.

Department of Prosthodontics and Dental Materials, University of Siena, 53100 Siena, Italy.

: The aim of this study was to investigate cuspal deflection caused by material shrinkage and temperature rise occurring in the pulp chamber during photopolymerization. The aim of this study was also to investigate the effect of flowable and packable bulk-fill composites on cuspal deflection occurring in mesio-occlusal-distal (MOD) cavities restored through the bulk-fill or through the incremental layering technique. Additionally, mechanical and thermal properties of bulk-fill composites were considered. Read More

View Article and Full-Text PDF
December 2020

The importance of the surface roughness and running band area on the bottom of a stone for the curling phenomenon.

Sci Rep 2020 Nov 26;10(1):20637. Epub 2020 Nov 26.

Professor Emeritus, Kitami Institute of Technology, 165 Koencho, Kitami, Hokkaido, 090-8507, Japan.

Curling is a sport in which players deliver a cylindrical granite stone on an ice sheet in a curling hall toward a circular target located 28.35 m away. The stone gradually moves laterally, or curls, as it slides on ice. Read More

View Article and Full-Text PDF
November 2020

Hands-on training based on quantifying radiant exposure improves how dental students cure composites: Skill retention at 2-year follow-up.

Eur J Dent Educ 2020 Nov 21. Epub 2020 Nov 21.

Dental Biomedical Science PhD Program, University of Maryland School of Dentistry, Baltimore, MD, USA.

Introduction: The durability and longevity of composite restoration are much dependent on the accurate delivery of the energy required to polymerise the material. This study aimed to investigate the extent to which undergraduate dental students acquire and retain light-curing skills following hands-on training.

Materials And Methods: Hands-on training comprises faculty tutoring for critical aspects of the light-curing procedure, such as distance and angulation of the light-curing tip. Read More

View Article and Full-Text PDF
November 2020

Chitosan Epoxidized Natural Rubber Biocomposites for Sorption and Biodegradability Studies.

ACS Omega 2020 Nov 28;5(44):28760-28766. Epub 2020 Oct 28.

School of Distance Education, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.

The slow-release mechanism of copper into soil followed by soil biodegradation was studied using the chitosan (CTS)/epoxidized natural rubber (ENR) biocomposite. The biocomposite was prepared by homogenizing CTS in ENR50 (ENR with about 50% epoxy content) latex in the presence of curing agents and acetic acid. It was found that the adsorption property of the biocomposite was very much influenced by chitosan loading, where 20phrCTS-t-ENR biocomposite can absorb 76. Read More

View Article and Full-Text PDF
November 2020

Color stability of a bulk-fill composite resin light-cured at different distances.

Braz Oral Res 2020 30;34:e119. Epub 2020 Oct 30.

Faculdade São Leopoldo Mandic - SLMandic, School of Dentistry , Department of Restorative Dentistry, Campinas , SP , Brazil .

The aim of this in vitro study was to evaluate the color stability of a bulk-fill (Filtek One Bulk Fill, 3M ESPE) and a conventional (Filtek Z350 XT, 3M ESPE) composite resin light-cured at different distances, before and after being submitted to staining with a coffee solution. Sixty specimens of each composite resin were prepared and light-cured at distances of 0, 2 and 4 mm, using a LED light-curing unit (Valo, Ultradent). The specimens were separated (n = 10) for immersion in either distilled water or coffee solution (10 minutes a day for 8 days) to stimulate staining. Read More

View Article and Full-Text PDF
November 2020

Absence of convection in solid tumors caused by raised interstitial fluid pressure severely limits success of chemotherapy-a numerical study in cancers.

Math Biosci Eng 2020 09;17(5):6128-6148

Competence Center Bioinformatics, Institute for Applied Computer Science, University of Applied Sciences Stralsund, Zur Schwedenschanze 15, 18435 Stralsund, Germany.

In comparison with lymphomas and leukemias, chemotherapy of solid neoplasms, i.e., cancer, has much more limited success in curing the patient. Read More

View Article and Full-Text PDF
September 2020

Effect of light-curing distance and curing time on composite microflexural strength.

Dent Mater J 2021 Jan 1;40(1):202-208. Epub 2020 Oct 1.

Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indiana University Purdue University Indianapolis.

This study investigated the influence of curing distance on µ-flexural strength (µ-FS) of a nano-hybrid composite, cured using the manufacturer-recommended curing time (MCT), compared to a consistent radiant exposure (CRE) using three different light-curing units (LCUs). Beams (6×2×1 mm) were cured using the MCT or CRE with a quartz-tungsten-halogen (QTH); a single-emission-peak light-emitting-diode (SLED), or a multiple-emission-peak light-emitting-diode (MLED) LCU. Specimens were cured at 0-, 2- or 8-mm distances (n=10) and the bottom irradiance and CRE were measured using a Managing Accurate Resin Curing-Resin Calibrator spectrometer. Read More

View Article and Full-Text PDF
January 2021

[Effect of orthodontic traction on the microstructure of dental enamel].

Nan Fang Yi Ke Da Xue Xue Bao 2020 Aug;40(8):1165-1171

School of Stomatology, Lanzhou University, Lanzhou 730000, China.

Objective: To investigate the effect of orthodontic traction on the microstructure of dental enamel.

Methods: Forty-eight isolated premolars were randomly divided into 6 groups (=8), including Group A (blank control group), in which the teeth were bonded with the orthodontic brackets without any loading force; Groups B1, B2, and B3 where the teeth were bonded with the orthodontic brackets using clinical adhesives and loaded with 50 g force for 6 months, 200 g force for 6 months, and 200 g force for 1 month, respectively; and Groups C1 and C2, where the teeth were bonded with straight wire brackets using light curing bonding and chemical curing bonding techniques, respectively. All the teeth were embedded with non-decalcified epoxy resin. Read More

View Article and Full-Text PDF

Gut bacterial communities and their contribution to performance of specialist Altica flea beetles.

Microb Ecol 2020 Nov 3;80(4):946-959. Epub 2020 Sep 3.

Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beichen West Road, Chaoyang District, Beijing, 100101, China.

Host plant shifts are a common mode of speciation in herbivorous insects. Although insects can evolve adaptations to successfully incorporate a new host plant, it is becoming increasingly recognized that the gut bacterial community may play a significant role in allowing insects to detoxify novel plant chemical defenses. Here, we examined differences in gut bacterial communities between Altica flea beetle species that feed on phylogenetically unrelated host plants in sympatry. Read More

View Article and Full-Text PDF
November 2020

Temperatures in the pulpal cavity during orthodontic bonding using an LED light curing unit : An in vitro pilot study.

J Orofac Orthop 2020 Nov 1;81(6):396-406. Epub 2020 Sep 1.

Department of Orthodontics, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.

Purpose: During bracket bonding, patients often report about thermosensitivity. The reason could be that modern light emitting diode (LED) light curing units run with intensities up to 3200 mW/cm. In this in vitro pilot study with nonpulpal circulation approaches, the temperatures in the pulpal cavity were measured. Read More

View Article and Full-Text PDF
November 2020

Performance and Sociodemographic Determinants of Excess Outpatient Demand of Rural Residents in China: A Cross-Sectional Study.

Int J Environ Res Public Health 2020 08 17;17(16). Epub 2020 Aug 17.

School of Medicine and Health Management, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.

Excess healthcare utilization is rapidly rising in rural China. This study focused on excess outpatient demand (EOD) and aimed to measure its performance and sociodemographic determinants among China's rural residents. A total of 1290 residents from four counties in central China were enrolled via multistage cluster random sampling. Read More

View Article and Full-Text PDF

The light-curing unit: An essential piece of dental equipment.

Int Dent J 2020 Dec 21;70(6):407-417. Epub 2020 Jul 21.

Faculty of Dentistry, Dalhousie University, Halifax, NS, Canada.

Introduction: This article describes the features that should be considered when describing, purchasing and using a light-curing unit (LCU).

Methods: The International System of Units (S.I. Read More

View Article and Full-Text PDF
December 2020

Assessment of the Change in Color of Maxillofacial Silicone after Curing Using a Mobile Phone Colorimeter Application.

J Contemp Dent Pract 2020 Apr 1;21(4):458-462. Epub 2020 Apr 1.

Trauma Care Center, Government Medical College, Nagpur, Maharashtra, India.

Aim: To evaluate the change in color of the maxillofacial silicone after curing using a mobile phone colorimeter application.

Materials And Methods: A two-piece metal mold was fabricated. Twenty five samples were made using M511, maxillofacial silicone. Read More

View Article and Full-Text PDF

Mechanical and Strain-Sensing Capabilities of Carbon Nanotube Reinforced Composites by Digital Light Processing 3D Printing Technology.

Polymers (Basel) 2020 Apr 22;12(4). Epub 2020 Apr 22.

Materials Science and Engineering Area, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, C/ Tulipán s/n, 28933 Móstoles, Madrid, Spain.

Mechanical and strain sensing capabilities of carbon nanotube (CNT) reinforced composites manufactured by digital light processing (DLP) 3D printing technology have been studied. Both CNT content and a post-curing treatment effects have been analyzed. It has been observed that post-curing treatment has a significant influence on mechanical properties, with an increase of Young's modulus and glass transition temperature whereas their effect in electrical properties is not so important. Read More

View Article and Full-Text PDF

Healthcare provider burn-out: A war with uncertainty.

Andrew S Valeras

Fam Syst Health 2020 Mar;38(1):96-98

Concord Hospital Family Health Center at Concord Hospital.

Referring to provider burn-out as a foe to be conquered is a palatable representation that fits within a familiar medical narrative-combating disease, fighting illness, curing and vanquishing the cancer. Even the words we use to describe our daily work-"on the front lines" or "in the trenches" or "fighting the good fight"-places us on a metaphorical battlefield. Is provider burn-out inflicted by another entity, and if so by whom or by what? Is it, by contrast, a disease or a condition? Is burn-out something that just happens or is it created? The World Health Organization International Classification of Disease (World Health Organization, 2019) added burn-out in 2019, but also made a clear statement that this is an occupational phenomenon and not a medical condition. Read More

View Article and Full-Text PDF

Monitoring film coalescence from aqueous polymeric dispersions using atomic force microscopy: Surface topographic and nano-adhesion studies.

Asian J Pharm Sci 2020 Jan 3;15(1):104-111. Epub 2018 Nov 3.

UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N1AX, UK.

The aim of the investigation was to develop the use of topographic and nano-adhesion atomic force microscopy (AFM) studies as a means of monitoring the coalescence of latex particles within films produced from a pharmaceutically relevant aqueous dispersion (EudragitNE30D). Films were prepared via spin coating and analysed using AFM, initially via tapping mode for topographic assessment followed by force-distance measurements which allowed assessment of site-specific adhesion. The results showed that colloidal particles were clearly observed topographically in freshly prepared samples, with coalescence detected on curing via the disappearance of discernible surface features and a decrease in roughness indices. Read More

View Article and Full-Text PDF
January 2020

Outcomes of ultra-fast (3 s) photo-cure in a RAFT-modified resin-composite.

Dent Mater 2020 04 13;36(4):570-579. Epub 2020 Mar 13.

School of Medical Sciences and Photon Science Institute, University of Manchester, UK.

Objective: This study evaluates critical material properties resulting from ultra-fast (3 s) photo-polymerization at high radiant emittance of a pre-production, novel bulk-fill resin-based composite (RBC) modified for reversible addition-fragmentation chain transfer (RAFT) polymerization.

Methods: The output characteristics of the associated light curing unit (LCU) were measured on a laboratory-grade spectrometer. Real-time Fourier Transform Infrared Spectroscopy (FTIR) and mechanical investigations (depth-sensing indentation with a linear and spatial distribution of the measured properties, and three-point bend tests) were performed using, as reference material, an established bulk-fill RBC of comparable chemical composition. Read More

View Article and Full-Text PDF

The Effect of Exposure on the Autogenous Self-Healing of Ordinary Portland Cement Mortars.

Materials (Basel) 2019 Nov 27;12(23). Epub 2019 Nov 27.

Building Materials, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 97187 Luleå, Sweden.

Exposure conditions are critical for the autogenous self-healing process of Portland cement based binder matrixes. However, there is still a significant lack of fundamental knowledge related to this factor. The aim of this paper was to investigate and understand the effects of various potentially applicable curing solutions on the efficiency of the crack closure occurring both superficially and internally. Read More

View Article and Full-Text PDF
November 2019

Adhesive Joint Stiffness in the Aspect of FEM Modelling.

Materials (Basel) 2019 Nov 26;12(23). Epub 2019 Nov 26.

Department of Mechanical Engineering, Lublin University of Technology, 20-388 Lublin, Poland.

The paper presents the results of nanoindentation testing, carried out along the thickness of the adhesive joint joining sheets of aluminum alloy. The purpose of the tests was to determine changes in the Young's modulus in the joint resulting from the active impact of the joined aluminum alloy sheets on the adhesive during curing of the adhesive bond. Structural changes that take place during curing of the joint, especially in the boundary zone, can have a significant impact on the adhesive properties and consequently, on the adhesive joint strength. Read More

View Article and Full-Text PDF
November 2019

Influence of Light-curing Distances on Microflexural Strength of Two Resin-based Composites.

Oper Dent 2020 May/Jun;45(3):297-305. Epub 2019 Nov 21.

Objective: Our objective was to investigate the influence of different curing distances on microflexural strength and the microflexural modulus of two resin-based composites.

Methods: Two nanohybrid composites were used; Filtek Z250 (Z250) and Tetric EvoCeram (TEC). Rectangular specimens were prepared (2-mm wide × 1-mm deep × 6-mm long) light cured according to the manufacturer's instructions at 0-mm, 2-mm, and 8-mm distances (n=10) and were stored wet at 37°C for 24 hours. Read More

View Article and Full-Text PDF

UV Curable Conductive Ink for the Fabrication of Textile-Based Conductive Circuits and Wearable UHF RFID Tags.

ACS Appl Mater Interfaces 2019 Jul 22;11(30):27318-27326. Epub 2019 Jul 22.

Textile is a kind of emerging substrate for wearable printed electronics to realize recyclable smart products by versatile and low-cost screen printing. The high temperature sintering step is necessary to get high surface electrical conductivity, whereas most of the common fabrics have poor temperature endurance. Meanwhile, both rough surface and porous structure of fabrics are not beneficial to obtain high-resolution and high-quality circuits. Read More

View Article and Full-Text PDF

The Role of Superabsorbent Polymer on Strength and Microstructure Development in Cemented Dredged Clay with High Water Content.

Polymers (Basel) 2018 Sep 27;10(10). Epub 2018 Sep 27.

Institute for Underground Space and Geoenvironment, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China.

This paper presents the role of superabsorbent polymer (SAP) on strength and microstructure development in cemented clays with notably high water content. A series of unconfined compressive strength (UCS), scanning electron microscope (SEM) and X-ray diffraction (XRD) tests were performed to identify strength behavior and microstructure. Results showed that SAP significantly influenced the mechanical behavior of cemented clays with notably high water content, characterized by an increase in the unconfined compressive strength and a decrease in the after-curing water content with SAP content. Read More

View Article and Full-Text PDF
September 2018

Continuous Directional Water Delivery on the 3D-Printed Arrowhead Microstructure Array.

Materials (Basel) 2019 Mar 29;12(7). Epub 2019 Mar 29.

Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology (Zhejiang University of Technology), Ministry of Education & Zhejiang Province, Hangzhou 310014, China.

Unidirectional transport is attracting increasing attention in the field of microfluidics, because it does not require an external energy supply. However, most of the current self-driving structures are still plagued with persistent problems that restrict their practical applications. These include low transport velocity, short transport distance, and complex structure. Read More

View Article and Full-Text PDF