Review of High Level Endodontic Research in PubMed Index Journals from Iran

Introduction: This study aimed to evaluate patents as well as high level researches including systematic reviews/meta-analyses and randomized controlled clinical trials (RCT) published in scientific journals by Iranians endodontic. Materials and Methods: The study started with targeted searches of PubMed as well as World Intellectual Property Organization and United State Patent and Trademark Office. Results: There were 4 filed/granted patents, 2 systematic reviews/meta-analyses and 25 RCTs. Patents were related to endodontic/dental (bio)materials. Performing a topic sorting, 15 RCTs were about vital pulp therapy and 8 about anesthesia and pain. More than 55% of these articles originated from three University of Medical Sciences: Shahid Beheshti (22.2%), Kerman (18.5%) and Mashad (14.8%). Conclusion: Vital pulp therapy was the most important topic amongst endodontic high level evidence articles

Spatial, temporal, and spectral control towards quantitative tissue spectroscopic imaging in the spatial frequency domain

Spatial Frequency Domain Imaging (SFDI) is a non-contact wide-field spectroscopy technique that employs sinusoidal patterns of spatially modulated light as the excitation source. By obtaining the effective modulation transfer function of the diffusively reflected light from a turbid medium, it considers the contribution of reduced scattering and absorption coefficient to this function allowing for decoupling of the optical properties. The extracted optical properties at several wavelengths can provide quantitative information on concentration of tissue chromophores such as hemoglobin, fat, and water. It also delivers information on the arrangement of tissue structural components, mainly cells and extracellular matrix proteins. The technique has been utilized to investigate many phenomena in brain, kidney, and skin tissues.Enhancing spatial, temporal, and spectral information content in SFDI can give insight to tissue constituents, their dynamics, and distribution. In this work, we developed and validated three variations of SFDI instruments with design considerations to match specific applications:1. High Speed SFDI instrument that detects rat cortex dynamic optical and physiological properties at 17 frames per second following cardiac arrest and resuscitation.2. Hyperspectral SFDI instrument which measures tissue optical properties at 1000 spectral bins over a broad range, 580-950 nm, and can spatially resolve concentrations of oxy- deoxy- and met- hemoglobin as well as water and fat fractions. It utilizes principles of spatial scanning of the spectrally dispersed output of a supercontinuum laser.3. Single pixel SFDI instrument which takes advantage of high bandwidth available for spectral encoding using a single-element detector and sparse sampling based on compressed sensing to characterize tissue optical properties over a wide field of view, 35 mm × 35 mm

An efficient GPU implementation of cyclic reduction solver for high-order compressible viscous flow simulations

In this paper, the performance of the Cyclic Reduction (CR) algorithm for solving tridiagonal systems is improved with the aid of efficient global memory transactions on Graphics Processing Units (GPU). To achieve maximum memory throughput with a lower computational runtime, two different Sort algorithms are introduced for reordering the initial system of equations: direct and step-by-step. It is shown that the latter method is well-fitted to modern GPUs and achieves speedup of up to 3.47× in single precision and 2.1× in double precision compared to the CPU Thomas algorithm. By benefiting from the new global memory implementation, the CR solver could run 2×–100× faster compared to previous works on parallel tridiagonal solvers. The CR solver is also applied to 2D & 3D compressible viscous flow simulations using the high-order compact finite-difference scheme. In this matter, the procedure of filtering, primitive variables, and flux derivative calculations are carried out by using the parallel tridiagonal solver on the GPU device. The GPU-accelerated calculations achieve speedups between 1.9×–15.2× in 2D and 6.4×–20.3× in 3D simulations for different grid sizes compared to CPU computations. The computations are performed on the NVIDIA GTX480 GPU. The obtained results are compared to those achieved on a single core of Intel Core 2 Duo (2.7 GHz, 2 MB cache) in terms of calculation runtime

Sealing Ability of Three Commercial Mineral Trioxide Aggregates and an Experimental Root-End Filling Material

INTRODUCTION: The purpose of this study was to compare the sealability of three different commercial types of mineral trioxide aggregate (MTA) and calcium enrichment mixture (CEM) cement as an experimental root-end filling material. MATERIALS AND METHODS: Forty-six single rooted teeth were cleaned, shaped, and obturated. The apical 3 mm of each root was resected and root-end cavities with 3 mm depth were prepared. The samples were randomly divided into 4 experimental groups comprised of 10 roots each. The cavities were filled with CEM cement and MTAs. Six roots were used as positive and negative controls. Samples were prepared and then immersed in 1% methylene blue dye for 3 days. Roots were split longitudinally and examined under stereomicroscope. RESULTS: Positive and negative controls responded as expected. CEM cement showed the least mean dye penetration value. ANOVA revealed no statistically significant differences among experimental groups. CONCLUSION: It was concluded that the experimental CEM cement exhibited similar sealing property as commercial types of MTA

Shear Bond Strength of a Resin Cement to Different Alloys Subjected to Various Surface Treatments

Objectives: Micromechanical retention of resin cements to alloys is an important factor affecting the longevity of metal base restorations. This study aimed to compare the bond strength and etching pattern of a newly introduced experimental etchant gel namely Nano Met Etch with those of conventional surface treatment techniques for nickel-chrome (Ni-Cr) and high noble alloys.  Materials and Methods: A total of 120 discs (8×10×15 mm) were cast with Ni-Cr (n=20), high noble BegoStar (n=50) and gold coin alloys (n=50). Their Surfaces were ground with abrasive papers. Ni-Cr specimens received sandblasting and etching. High noble alloy specimens (begoStar and gold coin) received sandblasting, sandblasting-alloy primer, etching, etch-alloy primer and alloy primer alone. Cylindrical specimens of Panavia were bonded to surfaces using Tygon tubes. Specimens were subjected to micro-shear bond strength testing after storing at 37°C for 24 hours. Results: In gold coin group, the highest bond strength was achieved after sandblasting (25.82±1.37MPa, P<0.001) and etching+alloy primer (26.60 ± 5.47 MPa, P<0.01). The lowest bond strength belonged to sandblasting+alloy primer (17.79±2.96MPa, P<0.01). In BegoStar group, the highest bond strength was obtained in the sandblasted group (38.40±3.29MPa, P<0.001) while the lowest bond strength was detected in the sandblast+ alloy primer group (15.38±2.92MPa, P<0.001). For the Ni-Cr alloy, bond strength in the etched group (20.79±2.01MPa) was higher than that in the sandblasted group (18.25±1.82MPa) (P<0.01). Conclusions: For the Ni-Cr alloy, etching was more efficient than sandblasting but for the high noble alloys, higher Au content increased the efficacy of etching

Compressed single pixel imaging in the spatial frequency domain.

We have developed compressed sensing single pixel spatial frequency domain imaging (cs-SFDI) to characterize tissue optical properties over a wide field of view ( 35 ?? mm × 35 ?? mm ) using multiple near-infrared (NIR) wavelengths simultaneously. Our approach takes advantage of the relatively sparse spatial content required for mapping tissue optical properties at length scales comparable to the transport scattering length in tissue ( l tr ? 1 ?? mm ) and the high bandwidth available for spectral encoding using a single-element detector. cs-SFDI recovered absorption ( ? a ) and reduced scattering ( ? s ? ) coefficients of a tissue phantom at three NIR wavelengths (660, 850, and 940 nm) within 7.6% and 4.3% of absolute values determined using camera-based SFDI, respectively. These results suggest that cs-SFDI can be developed as a multi- and hyperspectral imaging modality for quantitative, dynamic imaging of tissue optical and physiological properties

Hyperspectral imaging in the spatial frequency domain with a supercontinuum source.

We introduce a method for quantitative hyperspectral optical imaging in the spatial frequency domain (hs-SFDI) to image tissue absorption (μa) and reduced scattering (μs) parameters over a broad spectral range. The hs-SFDI utilizes principles of spatial scanning of the spectrally dispersed output of a supercontinuum laser that is sinusoidally projected onto the tissue using a digital micromirror device. A scientific complementary metal-oxide-semiconductor camera is used for capturing images that are demodulated and analyzed using SFDI computational models. The hs-SFDI performance is validated using tissue-simulating phantoms over a range of μa and μs values. Quantitative hs-SFDI images are obtained from an ex-vivo beef sample to spatially resolve concentrations of oxy-, deoxy-, and met-hemoglobin, as well as water and fat fractions. Our results demonstrate that the hs-SFDI can quantitatively image tissue optical properties with 1000 spectral bins in the 580- to 950-nm range over a wide, scalable field of view. With an average accuracy of 6.7% and 12.3% in μa and μs, respectively, compared to conventional methods, hs-SFDI offers a promising approach for quantitative hyperspectral tissue optical imaging