- Comparison of color stability and fracture resistance of two temporary fiber-reinforced fixed partial denture materials. [Journal Article]
- DRDent Res J (Isfahan) 2019 May-Jun; 16(3):185-192
- CONCLUSIONS: Coffee is considered as one of the most important factors affecting color changes in provisional FPDs, either in composite resins or in PMMAs. Fracture resistance of both composite resin and PMMA FPDs revealed no significant differences between the groups; however, there were significant differences between the nonreinforced and fiber-reinforced FPDs in both groups.
- Glass fiber supported BiOI thin-film fixed-bed photocatalytic reactor for water decontamination under solar light irradiation. [Journal Article]
- JEJ Environ Sci (China) 2019; 80:277-286
- BiOI powder has been proved to be an efficient photocatalyst, but the difficulty in removing it from water after reaction limits its application in real water treatment. To solve this problem, a thin…
BiOI powder has been proved to be an efficient photocatalyst, but the difficulty in removing it from water after reaction limits its application in real water treatment. To solve this problem, a thin-film fixed-bed reactor (TFFBR) was set-up by developing a BiOI thin film on glass fiber cloth (GFC). The composition and structure of the as-prepared films were characterized with X-ray diffraction, X-ray photoelectron spectroscopy, field emission microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The BiOI thin film was made by painting a silica sol containing BiOI on GFC, which could be tailored to desired sizes to accommodate the TFFBR. The mass of BiOI on the GFC increased with the number of iterations of the painting process. SiO2 sol glued the BiOI particles tightly onto the GFC, making the thin film strong enough to resist fluid flushing in the TFFBR. The photocatalytic activity of the BiOI thin film was investigated by degrading bisphenol A (BPA) under simulated sunlight. Ninety eight percent of BPA (20 mg/L in 2 L) was degraded by the BiOI thin film sample of seven layers (GFC-7) on the TFFBR within 8 hr irradiation. The GFC-7 displayed good photocatalytic ability toward artificial sewage containing BPA in a wide pH range (5-9), and also demonstrated excellent durability and reusability. The working conditions were optimized and it was found that the thickness of the fluid film and residence time over the thin film were key factors affecting the photocatalytic efficiency.
- MEG Effects on Hydrolysis of Polyamide 66/Glass Fiber Composites and Mechanical Property Changes. [Journal Article]
- MMolecules 2019 Feb 20; 24(4)
- Polyamide66 (PA66) hydrolysis affects the mechanical properties of Polyamide66/glass fiber (PA66/GF) composites. We investigated the effects of monoethylene glycol (MEG) on the degree of hydrolysis a…
Polyamide66 (PA66) hydrolysis affects the mechanical properties of Polyamide66/glass fiber (PA66/GF) composites. We investigated the effects of monoethylene glycol (MEG) on the degree of hydrolysis and mechanical properties of four different commercial PA66/glass fiber composites. Using pyrolysis-gas chromatography/mass spectrometry (py-GC/MS), we identified the byproducts of PA66 composite hydrolysis: carboxylic acid and alkylamine substances. The degree of hydrolysis increased as the immersion time in MEG increased. However, the tensile and flexural properties decreased due to hydrolysis. The tensile strength decreased by 42⁻45%; however, elongation increased by 23⁻63%. When PA66 absorbs MEG at 130 °C, the materials molecular chains' bonding force decreased, resulting in increased elongation.
- Effect of supporting substrate on the failure behavior of a polymer-infiltrated ceramic network material. [Journal Article]
- JPJ Prosthet Dent 2019; 121(6):929-934
- CONCLUSIONS: The supporting substrate influenced the failure behavior of PICN. When the substrate had a higher elastic modulus than the restorative material, better mechanical behavior was observed.
- Strong and thermal-resistance glass fiber-reinforced polylactic acid (PLA) composites enabled by heat treatment. [Journal Article]
- IJInt J Biol Macromol 2019 May 15; 129:448-459
- Polylactic acid (PLA) is a biodegradable polymer derived from renewable resources, showing potentials in replacing traditional petroleum-based polymers, yet its brittleness and low thermal-resistance…
Polylactic acid (PLA) is a biodegradable polymer derived from renewable resources, showing potentials in replacing traditional petroleum-based polymers, yet its brittleness and low thermal-resistance limits its applications. Thus, glass fibers (GF) combined with heat treatment were used to prepare high-performance PLA. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were employed to analyze crystallization behavior of PLA/GF composite. Tensile, flexural and impact tests were conducted to investigate mechanical properties, and heat deflection temperature was measured to evaluate thermal resistance. GF can coincidently enhance strength, rigidity, and toughness of PLA. Isothermal heat treatment can further improve the mechanical properties regardless of GF content. Compared with neat PLA, the tensile strength, flexural modulus, and impact strength can be increased by 162.5%, 266.4%, 232.5%, respectively, in the presence of 20 wt% GF after isothermal heat treatment, and meanwhile heat deflection temperature can be increased from 50.6 °C to 148.8 °C. Both DSC and XRD analysis results indicated that GF can significantly enhance crystallization of PLA. Thus, not only GF but also enhanced crystallization led to the outstanding mechanical performance of PLA/GF composites. While GF shows little effect on thermal resistance, heat treatment can remarkably improve thermal stability, in particular for PLA/GF composites.
- Fracture Strength and Stress Distribution in Premolars Restored with Cast Post-and-Cores or Glass-Fiber Posts Considering the Influence of Ferule. [Journal Article]
- BRBiomed Res Int 2019; 2019:2196519
- CONCLUSIONS: Ferule effect was shown to be more important than post type in the analysis. Both posts showed potential to withstand functional loads irrespective of presence of ferule. However, the mean FS was lower than parafunctional loads for FPC in the absence of ferule.
- Fracture Resistance of Endodontically Treated Maxillary Premolars Restored With Different Methods. [Journal Article]
- ODOper Dent 2019 Jan/Feb; 44(1):E1-E11
- CONCLUSIONS: ETPs restored with conventional composite resin with or without horizontal fiber post, bulk-fill composite, and ceramic inlay showed fracture resistance similar to that of sound teeth. Conventional composite resin restorations exhibited the highest prevalence of unrepairable fractures, and the insertion of a horizontal fiber post decreased this prevalence. Intact teeth showed 100% of repairable fractures. It is difficult to extrapolate the results directly to a clinical situation due to the limitations of this study.
- Vital Sign Monitoring and Cardiac Triggering at 1.5 Tesla: A Practical Solution by an MR-Ballistocardiography Fiber-Optic Sensor. [Journal Article]
- SSensors (Basel) 2019 Jan 24; 19(3)
- This article presents a solution for continuous monitoring of both respiratory rate (RR) and heart rate (HR) inside Magnetic Resonance Imaging (MRI) environments by a novel ballistocardiography (BCG)…
This article presents a solution for continuous monitoring of both respiratory rate (RR) and heart rate (HR) inside Magnetic Resonance Imaging (MRI) environments by a novel ballistocardiography (BCG) fiber-optic sensor. We designed and created a sensor based on the Fiber Bragg Grating (FBG) probe encapsulated inside fiberglass (fiberglass is a composite material made up of glass fiber, fabric, and cured synthetic resin). Due to this, the encapsulation sensor is characterized by very small dimensions (30 × 10 × 0.8 mm) and low weight (2 g). We present original results of real MRI measurements (conventionally most used 1.5 T MR scanner) involving ten volunteers (six men and four women) by performing conventional electrocardiography (ECG) to measure the HR and using a Pneumatic Respiratory Transducer (PRT) for RR monitoring. The acquired sensor data were compared against real measurements using the objective Bland⁻Altman method, and the functionality of the sensor was validated (95.36% of the sensed values were within the ±1.96 SD range for the RR determination and 95.13% of the values were within the ±1.96 SD range for the HR determination) by this means. The accuracy of this sensor was further characterized by a relative error below 5% (4.64% for RR and 4.87% for HR measurements). The tests carried out in an MRI environment demonstrated that the presence of the FBG sensor in the MRI scanner does not affect the quality of this imaging modality. The results also confirmed the possibility of using the sensor for cardiac triggering at 1.5 T (for synchronization and gating of cardiovascular magnetic resonance) and for cardiac triggering when a Diffusion Weighted Imaging (DWI) is used.
- Evaluation of fiber posts vs metal posts for restoring severely damaged endodontically treated teeth: a systematic review and meta-analysis. [Meta-Analysis]
- QIQuintessence Int 2019; 50(1):8-20
- CONCLUSIONS: It was concluded that fiber posts displayed higher medium-term (3 to 7 years) overall survival rates than did metal posts when used in the restoration of endodontically treated teeth with no more than two coronal walls remaining.
New Search Next
- Do Mechanical Advantages Exist in Relining Fiber Posts with Composite Prior to its Cementation? [Journal Article]
- JAJ Adhes Dent 2018; 20(6):511-518
- CONCLUSIONS: Relined fiberglass posts reduced the stress generated by polymerization shrinkage and showed greater bond strength to dentin.