Long-term efficacy, safety and biocompatibility of a novel sirolimus eluting iron bioresorbable scaffold in a porcine model.

Iron is considered as an attractive alternative material for bioresorbable scaffolds (BRS). The sirolimus eluting iron bioresorbable scaffold (IBS), developed by Biotyx Medical (Shenzhen, China), is the only iron-based BRS with an ultrathin-wall design. The study aims to investigate the long-term efficacy, safety, biocompatibility, and lumen changes during the biodegradation process of the IBS in a porcine model.

Biomaterials science and surface engineering strategies for dental peri-implantitis management.

Peri-implantitis is a bacterial infection that causes soft tissue inflammatory lesions and alveolar bone resorption, ultimately resulting in implant failure. Dental implants for clinical use barely have antibacterial properties, and bacterial colonization and biofilm formation on the dental implants are major causes of peri-implantitis. Treatment strategies such as mechanical debridement and antibiotic therapy have been used to remove dental plaque.

Antennal and proboscis sensilla characteristics of Paranthrene tabaniformis (Lepidoptera: Sesiidae).

The poplar clearwing moth, Paranthrene tabaniformis (Lepidoptera: Sesiidae) is a serious wood-boring pest of several trees. The ultramorphology of the antennae and proboscis sensilla of adult P. tabaniformis was examined using scanning electron microscope to determine their structures and sex-specific differences.

Biodegradation behavior of micro-arc oxidation coating on magnesium alloy-from a protein perspective.

Protein exerts a critical influence on the degradation behavior of absorbable magnesium (Mg)-based implants. However, the interaction mechanism between protein and a micro-arc oxidation (MAO) coating on Mg alloys remains unclear. Hereby, a MAO coating was fabricated on AZ31 Mg alloy.

Corrosion resistance and antibacterial activity of zinc-loaded montmorillonite coatings on biodegradable magnesium alloy AZ31.

A Zinc-loaded montmorillonite (Zn-MMT) coating was hydrothermally prepared using Zn ion intercalated sodium montmorillonite (Na-MMT) upon magnesium (Mg) alloy AZ31 as bone repairing materials. Biodegradation rate of the Mg-based materials was studied via potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and hydrogen evolution tests. Results revealed that both Na-MMT and Zn-MMT coatings exhibited better corrosion resistance in Dulbecco's modified eagle medium (DMEM) + 10% calf serum (CS) than bare Mg alloy AZ31 counterparts.

Design, synthesis and characterization of poly (methacrylic acid-niclosamide) and its effect on arterial function.

We have found that niclosamide induced relaxation of constricted artery. However, niclosamide is insoluble, the low bioavailability and the resultant low plasma concentration limit its potential exertion in vivo. The aim of the present study is to synthesize a soluble poly (methacrylic acid-niclosamide) polymer (PMAN) and study the effects of PMAN on arterial function in vitro and the blood pressure and heart rate of rats in vivo.

Azo polymeric micelles designed for colon-targeted dimethyl fumarate delivery for colon cancer therapy.

Unlabelled: Colon-targeted drug delivery and circumventing drug resistance are extremely important for colon cancer chemotherapy. Our previous work found that dimethyl fumarate (DMF), the approved drug by the FDA for the treatment of multiple sclerosis, exhibited anti-tumor activity on colon cancer cells. Based on the pharmacological properties of DMF and azo bond in olsalazine chemical structure, we designed azo polymeric micelles for colon-targeted dimethyl fumarate delivery for colon cancer therapy.

In Vitro Corrosion and Cytocompatibility of a Microarc Oxidation Coating and Poly(L-lactic acid) Composite Coating on Mg-1Li-1Ca Alloy for Orthopedic Implants.

Manipulating the degradation rate of biomedical magnesium alloys poses a challenge. The characteristics of a microarc oxidation (MAO), prepared in phytic acid, and poly(L-lactic acid) (PLLA) composite coating, fabricated on a novel Mg-1Li-1Ca alloy, were studied through field emission scanning electron microscopy (FE-SEM), electron probe X-ray microanalysis (EPMA), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The corrosion behaviors of the samples were evaluated via hydrogen evolution, potentiodynamic polarization and electrochemical impedance spectroscopy in Hanks' solution.

ProFile Vortex and Vortex Blue Nickel-Titanium Rotary Instruments after Clinical Use.

Introduction: The aim of this study was to analyze the incidence and mode of ProFile Vortex and Vortex Blue instrument defects after clinical use in a graduate endodontic program and to examine the impact of clinical use on the instruments' metallurgical properties.

Methods: A total of 330 ProFile Vortex and 1136 Vortex Blue instruments from the graduate program were collected after each had been used in 3 teeth. The incidence and type of instrument defects were analyzed.

In vitro cytotoxicity of calcium silicate-containing endodontic sealers.

Introduction: The cytotoxicity of 2 novel calcium silicate-containing endodontic sealers to human gingival fibroblasts was studied.

Methods: EndoSequence BC (Brasseler, Savannah, GA), MTA Fillapex (Angelus Indústria de Produtos Odontológicos S/A, Londrina, PR, Brazil) and a control sealer (AH Plus; Dentsply DeTrey GmbH, Konstanz, Germany) were evaluated. Human gingival fibroblasts were incubated for 3 days both with the extracts from fresh and set materials in culture medium and cultured on the surface of the set materials in Dulbecco-modified Eagle medium.

Effects of 5-amino salicylic acid on the expression of multidrug resistance gene in ulcerative colitis.

Background/aims: To study the effect of drugs on the expression of multidrug resistance gene in ulcerative colitis.

Methodology: The expressions of multidrug resistance (MDR) 1 gene and its product P-Gp were detected by reverse transcription-polymerase chain reaction and immunohistochemistry to realize the impact of drugs on ulcerative colitis.

Results: MDR1 gene and P-Gp did not exhibit significant difference (P > 0.

Physical properties of 5 root canal sealers.

Introduction: The aim of this study was to evaluate the pH change, viscosity and other physical properties of 2 novel root canal sealers (MTA Fillapex and Endosequence BC) in comparison with 2 epoxy resin-based sealers (AH Plus and ThermaSeal), a silicone-based sealer (GuttaFlow), and a zinc oxide-eugenol-based sealer (Pulp Canal Sealer).

Methods: ISO 6876/2001 specifications were followed. The pH change of freshly mixed and set sealers was evaluated during periods of 1 day and 5 weeks, respectively.

Phase transformation behavior and mechanical properties of thermomechanically treated K3XF nickel-titanium instruments.

Introduction: The bending and torsional properties of thermomechanically treated K3XF (SybronEndo, Orange, CA) nickel-titanium instruments in relation to their phase transformation behavior were evaluated.

Methods: NiTi instruments K3 (SybronEndo) and K3XF, both in sizes 25/.04 and 40/.

In vitro cytotoxicity evaluation of a novel root repair material.

Introduction: This study examined the effect of a new bioactive dentin substitute material (Biodentine) on the viability of human gingival fibroblasts.

Methods: Biodentine, White ProRoot mineral trioxide aggregate (MTA), and glass ionomer cement were evaluated. Human gingival fibroblasts were incubated for 1, 3, and 7 days both in the extracts from immersion of set materials in culture medium and directly on the surface of the set materials immersed in culture medium.

Current challenges and concepts of the thermomechanical treatment of nickel-titanium instruments.

Introduction: The performance and mechanical properties of nickel-titanium (NiTi) instruments are influenced by factors such as cross-section, flute design, raw material, and manufacturing processes. Many improvements have been proposed by manufacturers during the past decade to provide clinicians with safer and more efficient instruments.

Methods: The mechanical performance of NiTi alloys is sensitive to their microstructure and associated thermomechanical treatment history.

ProFile Vortex instruments after clinical use: a metallurgical properties study.

Introduction: The aim of the study was to analyze the incidence and mode of ProFile Vortex instrument (Dentsply Tulsa Dental Specialties, Tulsa, OK) defects during a predefined schedule of clinical use by the undergraduate students in a dental school setting and to examine the metallurgical characteristics of unused and clinically used Vortex instruments.

Methods: A total of 2,203 ProFile Vortex instruments discarded after single use from the undergraduate students program over 24 months were collected and examined for defects using a stereomicrosocpe at 10× magnification. The incidence and type of instrument defects or separation were analyzed.

Mechanical properties of controlled memory and superelastic nickel-titanium wires used in the manufacture of rotary endodontic instruments.

Introduction: The aim of this study was to investigate the structure and mechanical properties of newly developed controlled memory (CM) nickel-titanium wires used in the manufacture of rotary endodontic instruments.

Methods: The composition and the phase transformation behavior of both types of wires were examined by x-ray energy dispersive spectroscopy and differential scanning calorimetry, respectively. Conventional superelastic (SE) nickel-titanium wire was used as a control.

Ti-Ge binary alloy system developed as potential dental materials.

As-cast Ti-xGe (x = 2, 5, 10, 20 wt %) binary alloys were produced in this work, and various experiments were carried out to investigate the microstructure, mechanical properties, in vitro electrochemical and immersion corrosion behaviors as well as cytotoxicity with as-cast pure Ti as control, aiming to study the feasibility of Ti-xGe alloy system as potential dental materials. The microstructure of Ti-xGe alloys changes from single α-Ti phase to α-Ti + Ti(5)Ge(3) precipitation phase with the increase of Ge content. Mechanical tests show that Ti-5Ge alloy has the best comprehensive mechanical properties.

[Fracture analyses of casting framework removable partial dentures].

Objective: To compare the clinical fracture rates of removable partial denture (RPD) made of titanium with that of Co-Cr alloy, to analyze the fracture modes and reasons of two kinds of metal frameworks, and to explore the effect of defects on the fracture process.

Methods: Following totally 30 618 RPDs made by titanium and by Co-Cr alloy, the fracture rates in 18-month were calculated individually. The fractured surfaces of failed RPDs were examined by fractography investigations using a field emission scanning electron microscope to disclose the fracture mode and damage character.

Comparison of sildenafil with strontium fructose diphosphate in improving erectile dysfunction against upregulated cavernosal NADPH oxidase, protein kinase Cε, and endothelin system in diabetic rats.

Objectives: Phosphodiesterase type 5 inhibitors are potent in relieving erectile dysfunction (ED), however, they are less satisfactory in diabetic patients, probably due to the pro-inflammatory biomarkers caused by diabetes. Therefore, it was interesting to compare the effects of sildenafil with strontium fructose 1,6-diphosphate (FDP-Sr) on cavernosal vascular activity and expressions of pro-inflammatory biomarkers in diabetic rats.

Methods: Male Sprague-Dawley rats were injected with streptozocin (60 mg/kg, i.

Metallurgical characterization of controlled memory wire nickel-titanium rotary instruments.

Introduction: To improve the fracture resistance of nickel-titanium (NiTi) files, manufacturers have introduced new alloys and developed new manufacturing processes for the fabrication of NiTi files. This study aimed to examine the phase transformation behavior and microstructure of NiTi instruments from a novel controlled memory NiTi wire (CM wire).

Methods: Instruments of EndoSequence (ES), ProFile (PF), ProFile Vortex (Vortex), Twisted Files (TF), Typhoon (TYP), and Typhoon™ CM (TYP CM), all size 25/.

Influence of cross-sectional design and dimension on mechanical behavior of nickel-titanium instruments under torsion and bending: a numerical analysis.

Introduction: The aim of this study was to examine the influence of the cross-sectional configuration and dimensions (size and taper) on the torsional and bending behavior of nickel-titanium rotary instruments, taking into account the nonlinear mechanical properties of material.

Methods: Ten cross-sectional configurations, square, triangular, U-type, S-type (large and small), convex-triangle, and 4 proprietary ones (Mani NRT and RT2, Quantec, and Mtwo), were analyzed under torsion or bending by using a 3-dimensional finite element method. The von Mises stresses were correlated with the critical values for various phases of the nickel-titanium material.

The application of poly (glycerol-sebacate) as biodegradable drug carrier.

Poly (glycerol-sebacate) (PGS) is an elastomeric biodegradable polymer which possesses the ideal properties of drug carriers. In the present study, we prepared a series of PGS implants (5-FU-PGSs) loaded with different weight percent of 5-fluorouracil (2, 5, 7.5 and 10%).

Calcification capacity of porous pHEMA-TiO₂ composite hydrogels.

Many investigations have been attempted to promote calcification of synthetic polymers for applications as orthopaedic and dental implants. In this study, novel titanium dioxide (TiO(2)) reinforced porous poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels were synthesized. Calcification capacity of the composite polymers was examined using light microscopy, scanning electron microscopy and Fourier transform infrared spectroscopy after incubation of the materials in a simulated body fluid up to 53 days.