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Automated mineralogy is a software addition usually seen on scanning electron microscopes designed to provide rapid insight into sample chemistry and texture in routine petrology workflows. The specific purpose of automated mineralogy is to provide mineral classifications to uniquely identified phases typically using energy dispersive spectroscopy, thus removing laborious and time‐consuming human input for routine tasks. These mineral classifications can then be applied to image data to quantify which mineral is associated with any particular texture. Automated mineralogy systems were primarily designed to generate quantitative textural analysis of particle samples to the mining industry and have remained a critical technique in this setting for the last several decades. Automated mineralogy has become more widely used in academia, and this has changed the focus of the technique, applying it to a broader range of workflows and applications. Here we show petrology examples focussing where combined geochemical and textural analysis are widely used. Critically, the use of quantitative geochemical data means that mineral classifications are based on their quantitatively measured chemistry. By making both the chemical and textural analysis quantitative, automated mineralogy can become highly flexible and provide a unique system for petrologists in both industry and academia. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Odontologica Latinoamericana: AOL is the property of Acta Odontologica Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Accurate segmentation of 3D micro CT scans is a key step in the process of analysis of the microstructure of porous materials. In polar ice core studies, the environmental effects on the firn column could be detected if the microstructure is digitized accurately. The most challenging task is to obtain the microstructure parameters of the bubbly ice section. To identify the minimum, necessary resolution, the bubbly ice micro CT scans with different resolutions (120, 60, 30, 12 μm) were compared object-wise via a region pairing algorithm. When the minimum resolution was found to be 60 μm, for generating the training/validation dataset, 4 ice core samples from a depth range of 96 to 108 meters (bubbly ice) were scanned with 120 μm (input images) and another time with 4 times higher resolution (30 μm) to build ground truth. A specific pipeline was designed with non-rigid image registration to create an accurate ground truth from 4 times higher resolution scans. Then, two SOTA deep learning models (3D-Unet and FCN) were trained and later validated to perform super-resolution segmentation by taking input of 120μm resolution data and giving the output of binary segmented with two times higher resolution (60μm). Finally, the outputs of CNN models were compared with traditional rule-based and unsupervised methods on blind test data. It is observed the 3D-Unet can segment low-resolution scans with an accuracy of 96% and an f1-score of 80.8% while preserving microstructure having less than 2% error in porosity and SSA.

Tortuosity (τ ) is one of the key parameters controlling flow and transport in porous media. Although the concept of tortuosity is straightforward, its estimation in porous media has yet been challenging. Most models proposed in the literature are either empirical or semiempirical including some parameters whose values and their estimations are in prior unknown. In this study, we modified a previously presented geometric tortuosity ( τ g ) model based on percolation theory and validated it against a methodology based on the pathfinding A* algorithm. For this purpose, we selected 12 different porous materials including four sandstones, three carbonates, one salt, and four synthetic media. For all samples, five sub-volumes at different lengths with fifty iterations were randomly selected except one carbonate sample for which three sub-volumes were extracted. Pore space properties, such as pore radius, throat radius, throat length, and coordination number distributions were determined by extracting the pore network of each sub-volume. The average and maximum coordination numbers and minimum throat length were used to estimate the τ g . Comparison with the A* algorithm results showed that the modified model estimated the τ g accurately with absolute relative errors less than 28%. We also estimated the τ g using two other models presented in the literature as well as the original percolation-based tortuosity model. We found that our proposed model showed a significantly higher accuracy. Results also indicated more precise estimations at the larger length scales demonstrating the effect of uncertainties at the smaller scales. [ABSTRACT FROM AUTHOR]

Continuous monitoring of implanted vascular implants poses challenges due to the inherent toxicity and instability of contrast agents within the body. The use of biocompatible materials with radiopaque properties offers a solution for continuous monitoring of implanted artificial grafts together with early detection of vascular prosthesis dysfunction, which mitigates the risk of catastrophic failures from leakages or aneurysms. Here, we aimed to develop an artificial vascular graft with enhanced radiopacity to facilitate postsurgery monitoring. To achieve this goal, MXene (Ti3C2 nanosheets) was incorporated into poly-(methyl methacrylate) (PMMA)/polydimethylsiloxane (PDMS) nanofibers via an electrospinning technique, to enhance radiopacity without compromising biocompatibility. The integration of MXene into the nanofiber resulted in an increase in the hydrophilicity of the samples, leading to enhanced cell attachment. Microcomputed tomography imaging was used to verify the radiopacity properties of the samples, showing excellent contrast characteristics. The biocompatibility and hemocompatibility of the samples showed that 50 wt % MXene is the optimal concentration, demonstrating no cytotoxic effects. This is due to the encapsulation of MXene inside the PMMA/PDMS nanofibers preventing the interaction of MXene nanosheets with the physiological environment in vitro while maintaining their radiopacity. This approach herein holds promise as a platform for the long-term monitoring of implanted polymeric materials, thereby addressing a critical unmet need in the field. [ABSTRACT FROM AUTHOR]

BACKGROUND: Low to moderate intensity aerobic exercise can help protect knee cartilage. Long-chain non-coding RNAs are crucial for gene regulation. Among them, HOTAIR can activate numerous transcriptional co-repressors to repress the activation of certain genes. OBJECTIVE: To detect the expression levels of HOX transcript antisense RNA (HOTAIR) and other related factors in chondrocytes of high fat-fed mice and after low to moderate intensity exercise intervention, and to investigate their role in cartilage injury and sports rehabilitation. METHODS: Thirty C57BL/6 male mice were randomly divided into control group (normal feeding), high fat feeding group and high fat feeding plus treadmill exercise group, with 10 mice in each group. The mice in the high fat feeding plus treadmill exercise group were subjected to an 8-week low to middle intensity treadmill exercise, and the mice in the other two groups were caged. During this period, body mass was weighed every week on Sunday. After the 8-week exercise, both lower extremities of mice were taken, and the knee joint was scanned using Micro CT to make a 3D femoral condyle image to obtain relevant parameters. Hematoxylin-eosin and safranin O-fast green staining of the knee joint were performed for Mankin and Osteoarthritis Research Society International (OARSI) scoring. RT-PCR was performed to detect the mRNA levels of cartilage metabolic indicators and lipid metabolism indicators, including type II collagen, matrix metalloproteinase 13, interleukin 1, low-density lipoprotein receptor-related protein 5, HOTAIR and its downstream factor lysine specific demethylase 1. RESULTS AND CONCLUSION: The body mass of high fat-fed mice were higher than that of the control group (P < 0.01), and the body mass of the high fat feeding plus treadmill exercise group was lower than that of the high fat feeding group (P < 0.05). The connectivity density of high fat-fed mice was higher than that of the control group (P < 0.01). Mankin and OARSI scores of the high fat feeding were higher than those of the control group (P < 0.01) and high fat feeding plus treadmill exercise group (P < 0.05). The mRNA level of type II collagen was higher in the control group than the high fat feeding plus treadmill exercise group (P < 0.05) and high fat feeding group (P < 0.01) as well as higher in the high fat feeding plus treadmill exercise group than the high fat feeding group (P < 0.01). The mRNA levels of matrix metalloproteinase 13, interleukin 1, low-density lipoprotein receptor-related protein 5, HOTAIR and lysine specific demethylase 1 were higher in the high fat feed group than the control group and high fat feeding plus treadmill exercise group (P < 0.01). To conclude, high fat feeding can increase the bone substance of the femoral condyle, lead to knee cartilage wear, and cause chondrocyte metabolism disorder. HOTAIR is highly expressed in this process. An 8-week low to middle intensity treadmill exercise can reduce body mass, alleviate knee cartilage wear, improve chondrocyte function and down-regulate HOTAIR expression in mice. [ABSTRACT FROM AUTHOR]

This study aims to suggest a new method for predicting 3D sphericity through traditional 2D image processing through a novel sieving analysis. The 3D sphericity indices of grains (over 3000 particles for each material) from seven irregular granular materials are determined using μCT slices. These indices are then compared with existing 2D indices obtained through SEM image processing. Additionally, seven synthetic materials (semi-regular in size and shape) are also assessed to account for unusual particle shapes. The findings shed light on the role of sphericity in the rate at which particles pass through sieve openings. The results indicate that the initial passing rate of grains is strongly correlated with the 3D sphericity indices, which significantly decrease as sphericity decreases. The proposed method involves a sequential sieving test, performed similarly to the conventional sieving test but conducted sequentially at different time steps. Several correlations between 3D sphericity and its 2D counterparts are presented, which can successfully predict the 3D sphericity indices. Additionally, two empirical equations are proposed to predict the most frequent flatness and elongation aspect ratios, used in the Zingg diagram. Furthermore, the grading analysis derived from both 2D and 3D image processing is compared with sieve analysis. The results show that, unlike the 2D results, the grading curves obtained from 3D image processing are in excellent agreement with the sieve analysis. A corrected grading curve, derived from traditional 2D image processing, is proposed to align with 3D grading curves. [ABSTRACT FROM AUTHOR]

Over the past decade, studies published on the evaluation of intraoral scanners (IOSs) have mainly considered two parameters, precision and trueness, to determine accuracy. The third parameter, resolution, not much studied, seems essential for an application in dentistry. Objective: The objective of this preliminary study is to create an original method - a Resolution-Trueness-Precision (RTP) protocol to evaluate these three main parameters - resolution trueness and precision - at the same time. Material and Method: A ceramic tip with particular and calibrated dimensions is determined as the reference object and its mesh recorded with a scanning microtomograph, and compared with the one extracted to the IOS. It is the particular geometric shape of the object that will make it possible to simultaneously assess: resolution, trueness and precision. Results: The results have shown a mean resolution of 79.2 μm, a mean for trueness of 17.5 and a mean for precision of 12.3 μm. These values are close to previous results published for this camera. So, the RTP protocol is the first including the three parameters at the same time. Simple, fast and precise, its application can be useful for comparisons between IOSs within research laboratories or test organizations. Finally, this study could be a first step to create a reference kit for practitioners allowing them to control the quality of their IOS over time. [ABSTRACT FROM AUTHOR]

Faster and predictable osseointegration is crucial for the success of dental implants, especially in patients with compromised local or systemic conditions. Despite various surface modifications on the commercially available Titanium (Ti) dental implants, the bioactivity of Ti is still low. Thus, to achieve both biological and therapeutic activity on titanium surfaces, surface modification techniques such as titanium nanotubes have been studied as nanotube surfaces can hold therapeutic drugs and molecules. The main aim of the present research work is to study the early osseointegration around the novel Simvastatin drug eluting nanotubular dental implant. In the present research, the titanium nanotubes were fabricated on the screw-shaped dental implant surface and the Simvastatin drug was loaded into the nanotubes using the ultrasonication dip method. In vitro and In vivo studies were carried out on the modified dental implants. In vitro cell culture study reported enhanced osteogenic activity on the drug-loaded nanotube surface implants. The in vivo animal studies were evaluated by micro-CT, histopathology, and reverse torque removal analysis methods. The test results showed faster osseointegration with the strong interface on the Simvastatin drug-loaded implant surface at 4 weeks of healing as compared to the control implants.

The vast majority of cephalopods of the order Tarphyceratida are known from regions that were located at mid- or low palaeolatitudes during the Ordovician (mainly Baltica, Laurentia, and Chinese palaeoblocks). Only a handful of tarphyceratid specimens are known from high palaeolatitude regions of peri-Gondwana and Gondwana. Here, we describe the two best-preserved trocholitid cephalopods known to date from the Ordovician of the Prague Basin. The first is from the late Darriwilian/early Sandbian Dobrotivá Formation and is assigned to Trocholites fugax, a species previously recorded from roughly coeval strata of Iberia, France, and Bohemia. The specimen thus strengthens previous hypotheses regarding the interchange of non-benthic faunas between Baltica and different regions of peri-Gondwana during the Middle/ Late Ordovician boundary interval. The second specimen, assigned to a new species of Trocholites chaloupkai sp. nov., is from the late Sandbian–early Katian Zahořany Formation and thus represents one of the stratigraphically youngest Trocholites in the Ordovician of peri-Gondwana. Internal structures of the shell of the holotype of the new species were studied using micro-CT tomography. This revealed that T. chaloupkai sp. nov. closely resembles the stratigraphically older (Darriwilian) species Trocholites depressus from Estonia.

Osteogenesis imperfecta (OI) is an inherited congenital disorder, characterized primar- ily by decreased bone mass and increased bone fragility. Bone morphogenetic protein-2 (BMP-2) is a potent cytokine capable of stimulating bone formation, however, its rapid degradation and unanticipated in vivo effects restrict its application. The sustained release characteristic of silk fibroin (SF) microspheres may potentially address the aforementioned challenges, nevertheless they have not previously been tested in OI treatment. In the current investigation, recombinant BMP-2 (rBMP-2) loaded SF (rBMP-2/SF) microspheres-based release carriers were prepared by physical adsorption. The SF microparticles were characterized by scanning electron microscopy (SEM) and were investigated for their cytotoxicity behavior as well as the release profile of rBMP-2. The rBMP-2/SF microspheres were administered via femoral intramedullary injection to two genotypes of OI-modeled mice daily for two weeks. The femoral microstructure and histological performance of OI mice were evaluated 2 weeks later. The findings suggested that rBMP-2/SF spheres with a rough surface and excellent cytocompatibility demonstrated an initial rapid release within the first three days (22.15 ± 2.88% of the loaded factor), followed by a transition to a slower and more consistent release rate, that persisted until the 15th day in an in vitro setting. The factor released from rBMP-2/SF particles exhibited favorable osteoinductive activity. Infusion of rBMP-2/SF microspheres, as opposed to blank SF spheres or rBMP-2 monotherapy, resulted in a noteworthy enhancement of femoral microstructure and promoted bone formation in OI-modeled mice. This research may offer a new therapeutic approach and insight into the management of OI. However, further investigation is required to determine the systematic safety and efficacy of rBMP-2/SF microspheres therapy for OI. [ABSTRACT FROM AUTHOR]

The vast majority of cephalopods of the order Tarphyceratida are known from regions that were located at mid- or low palaeolatitudes during the Ordovician (mainly Baltica, Laurentia, and Chinese palaeoblocks). Only a handful of tarphyceratid specimens are known from high palaeolatitude regions of peri-Gondwana and Gondwana. Here, we describe the two best-preserved trocholitid cephalopods known to date from the Ordovician of the Prague Basin. The first is from the late Darriwilian/early Sandbian Dobrotivá Formation and is assigned to Trocholites fugax, a species previously recorded from roughly coeval strata of Iberia, France, and Bohemia. The specimen thus strengthens previous hypotheses regarding the interchange of non-benthic faunas between Baltica and different regions of peri-Gondwana during the Middle/ Late Ordovician boundary interval. The second specimen, assigned to a new species of Trocholites chaloupkai sp. nov., is from the late Sandbian–early Katian Zahořany Formation and thus represents one of the stratigraphically youngest Trocholites in the Ordovician of peri-Gondwana. Internal structures of the shell of the holotype of the new species were studied using micro-CT tomography. This revealed that T. chaloupkai sp. nov. closely resembles the stratigraphically older (Darriwilian) species Trocholites depressus from Estonia. [ABSTRACT FROM AUTHOR]

This current paper aims to review the literature on the root canal configuration (RCC) and root structure of permanent mandibular premolars. To find the published scientific literature on the RCC of mandibular premolars up to July 2022, a systematic search of four electronic databases was performed. The studies were selected, rendering to a predetermined point of reference: "mandibular 2nd premolar", "root and canal system", "morphology of root and canal", "root and canal configuration", and "morphology", along with "anatomy" and "mandibular premolars". Cross-referencing along with screening through the bibliographies of the chosen articles resulted in the identification of further studies. In the current study, we examined 30 different articles, and we chose them based on the quality of research investigations. From 3471 retrieved studies, a total of 15981 mandibular 2nd premolars were observed in 30 studies. The mean JBI score for studies assessing the structure of the root, as well as the root canal of the mandibular 2nd premolar, was 7.78 ± 0.81. We have found a pooled prevalence of 91.82% for Vertucci class I root canal morphology and 78.63% pooled prevalence of single-rooted mandibular second premolar. A total of 8677 mandibular 1st premolars were observed in 22 studies. The mean JBI score for studies assessing the structure and anatomy of the root, as well as root canal of mandibular 1st premolar, was 7. 95 ± 0.85. We have found a pooled prevalence of 74.34% for Vertucci class I root canal morphology and 85.20% pooled prevalence of single-rooted mandibular 1st premolar. Mandibular first and second premolars were mostly single-rooted teeth (89.5–100%). The most frequently seen RCC is a 1-1-2-/2 (type V–Vertucci's), followed by 1-1-2-/1 (type IV– Vertucci's; type III–Weine's), and finally RCC 2-2-2-1 (type IV–Vertucci's; type III–Weine's). Presently, the imaging of CBCT is the most used research approach for studying Mn2Ps' structural characteristics. [ABSTRACT FROM AUTHOR]

The use of sintered-wick heat pipes in heat exchanger performance-related studies gained popularity owing to the simplicity and affordability of heat pipes. Evaluation of the system performance may be based on various arrangements and numbers of heat pipes applicable to the literature. Wick porosity and permeability are critical parameters for the investigation of wick capillary pumping, which will ultimately determine heat pipe performance. Despite the significance of these parameters to thermal performance, they are difficult to obtain, as the methods for obtaining these parameters before installing the heat pipes are time-consuming and destructive. This study aims to investigate the feasibility of Micro Tomography (Micro CT) to observe the porosity of copper sintered-wick heat pipes. Visual data from three heat pipe samples, namely HP1, HP2, and HP3 are quantified and analyzed. Analysis of the average porosity of HP1 and HP2 samples showed a similar value of 47.6 and 48.1%, respectively; however, the value of porosity along the length of the scanned area shows a bigger range of 42–54%. The accuracy of Micro CT was tested by testing three porosity samples with designed porosity of 26%, 22.3%, and 16.6% which were 3D printed using atomic diffusion additive manufacturing technology. Each sample was designed with pore shapes hexagonal, circular, and elliptical, respectively. Micro CT visualization and analysis showed the porosity reduction of the 3D printed porosity samples compared to the CAD design. Due to the smallest reduction of porosity after the sintered process, the 3D printed sample with a hexagonal pore shape, and the designed porosity of 26%, this sample was recommended for sintered wick fabrication using this technology and to test the accuracy of Micro CT.

Purpose: The structural integrity of the resin cement layer, the bond strength, and the biomechanical behavior of different fiberglass post cementation techniques were evaluated. Methods: Thirty-three bovine incisors were divided into three groups (n = 11): conventional fiberglass post (CFP), conventional fiberglass post in flared root canals (CFL), and relined fiberglass post (RFP). Six specimens from each group were submitted for high-resolution microcomputed tomography (μCT) to evaluate the integrity and presence/volume of voids at the resin cement layer. Finite element analysis (FEA) of two three-dimensional (3D) models of each group were conducted, one considered ideal (without interface defects) and another containing the conditions identified in the μCT analysis. Push-out bond strength tests were conducted for all specimens. Results: The CFL group had the greatest mean values of void (Thirds cervical: 73.67; middle: 95.67; apical: 47.33) and gap concentration (Thirds cervical: 14.67; middle: 15.83; apical: 8.33) compared with CFP and RFP. A significant difference in bond strength was observed between the cervical (1.33 MPa) and middle thirds (1.85 MPa) compared with the apical third (4.85 MPa) of the CFL. A significant difference was observed in the bond strength in the CFL (1.33 MPa) and RFP (3.29 MPa) in the cervical third, which were statistically similar to the bond strength of the CFP. The tensile stress distributions were similar in most structures, localized in the cervical region on the lingual surface. Conclusions: Structural defects in the interface layer might influence the bond strength and biomechanical behavior under the different fiberglass post cementations. [ABSTRACT FROM AUTHOR]

Development and application of hybrid membranes containing multi-component materials are increasing day by day in the fields of environmental protection and water treatment. In this research, the efficiency of titania nanowire (TiO2 NW)-based self-supported hybrid membranes was investigated in the removal of Escherichia coli (E. coli) bacteria and MS2 bacteriophages from contaminated water mimicking the microorganism suspension. Furthermore, toxicology tests on the as-prepared membranes were also performed. TiO2 NWs were coated with iron(III) oxide (Fe2O3) and copper(II) oxide (CuO) nanoparticles, respectively, and cellulose was used as reinforcement material. It was found that, the functionalisation strongly affected the MS2 removal ability of as-prepared membranes, which can be due to the electrostatic interactions between the surface of hybrid membrane and the bacteriophages. The most efficient removal (greater than or equal to 99.99%) was obtained with the TiO2 NW-CuO-cellulose membrane at pH 7.0. The fabricated hybrid membranes were characterized by micro computed tomography (μCT), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), contact angle measurement and inductively coupled optical emission spectrometry (ICP-OES) techniques. This study shows a simple route of the usage of novel and effective inorganic nanowire-based hybrid membranes for bacteria and virus removal, providing new pathways in the field of water filtration technologies.

Abstract Objective to determine the presence of marginal bacterial microfiltration in the IAI in different implant/abutment systems, in vitro. Material and methods Fifty‐six implants from seven different brand names, 4 with cone and 3 with straight connections were used, implant and abutment were connected using the Ncm tightening as indicated by each of the manufacturers and then were sealed. The samples were subjected occlusal load and thermal cycling, a first sample of each group was observed by micro CT and in a second sample (both samples randomly selected) length of connection was measured, while the rest of the samples were mounted on devices according to the bacterial microfiltration model with Porphyromonas gingivalis. Results Two of the conical connection system groups did not present bacterial microfiltration, one of the three straight connection groups only microfiltered in one sample, while the other two conical as well as the two straight connection samples showed different and important levels of bacterial microfiltration, all groups presented a direct relationship between the implant‐abutment adjustment determined by micro‐CT and bacterial microfiltration levels, not related to the connection length. Conclusion: Only two conical connection systems presented no bacterial microfiltration.

In order to study the mechanical behavior of solid rocket motor charge bonding interface under uniaxial tensile loading, the bonding interface of HTPB propellant/liner/insulator during uniaxial tensile process was scanned and reconstructed based on micro‐CT in‐situ loading, and the variation of porosity and interface debonding rate with strain was analyzed. A damage‐containing constitutive model based on the evolution of meso‐characteristic parameters was established for bonded interfacial components. The experimental analysis shows that the initial defects have a great influence on the location and evolution direction of the interface damage, and the interface damage can be quantitatively characterized by the interface debonding rate and porosity, and the interface debonding rate can better reflect the damage evolution process of micro‐pores and cracks near the propellant/liner interface. The damage‐containing constitutive model based on the evolution of mesoscopic characteristic parameters can effectively establish the structure‐activity relationship between mesoscopic parameters and macroscopic mechanical properties, and can predict the mechanical behavior of charge interface. [ABSTRACT FROM AUTHOR]

Three sets of snow specimens with different initial densities ranging from 311 to 486 kg m−3, which were collected from depths of 7, 40 and 57 cm at Summit, Greenland (72°35′ N, 38°25′ W) in June 2017, were subjected to the temperature gradient (TG) of ~160 K m−1 in opposing directions. The snow metamorphism was characterized using both X‐ray micro computed tomography and optical microscopy. The formation of depth hoar is evident as the snow grains transformed from the initial approximately rounded particles to needles, broad‐plates, columns and cup‐shapes. The de‐densification process of snow is also reflected in various microstructural parameters, viz., the density and the structure thickness (the feature size of ice particle) generally decreased with time, while the area‐equivalent circle diameter (the feature size of pore), the total porosity, the specific surface area and the structure model index (a measure of convexity/concavity of ice surface) increased. Based on an ice‐sphere pair of equal size, a vapour transport model, which depends on the initial particle radius, rp$$ {r}_p $$, and the ratio of the initial particle‐bond radius to the initial particle radius, α$$ \alpha $$, was constructed to simulate the main characteristics of change in the density with time under the TG metamorphism. We found critical values of rp$$ {\mathrm{r}}_p $$ = 0.1 mm and α$$ \alpha $$ = 0.1 that determine how fast the geometric coefficient, ψ$$ \psi $$ (a tuning parameter used in this model at the cone angle θ=45°$$ \theta =45{}^{\circ} $$ between the two ice spheres), changes. We propose a conceptual model in which an ice‐sphere pair can be regarded as a volume element of morphogenesis of depth hoar. This model can be used to explain the formation of the needle‐like, broad‐plate and column depth hoar by combining particle‐by‐particle with inter‐layer vapour transport. [ABSTRACT FROM AUTHOR]

Background and Objective: Different bone remodeling algorithms are used to predict bone adaptation and to understand how bones respond to the mechanical stimuli altered by implants. This paper introduces a novel micro-scale bone remodeling algorithm, which deviates from conventional methods by focusing on structure-based bone adaptation instead of density-based approaches., Methods: The proposed model simulated cellular activities such as bone resorption, new bone formation, and maturation of newly formed bone. These activities were assumed to be triggered by mechanical stimuli. Model parameters were evaluated for the 3D geometries of trabecular bone from intact femur developed from micro computed tomography (CT) scan data. Two different hip implants, solid and porous were used, and two different bone remodeling methods were performed using the proposed and conventional methods., Results: Results showed that micro CT scan-based finite element (FE) models accurately captured the microarchitecture and anisotropy of trabecular bone. The predicted bone resorption rate at the peri-prosthetic regions for the solid and porous implants was in the range of 17-27% and 4.5-7.3%, respectively, for a simulated period of four years., Conclusions: The results obtained from FE analysis strongly align with clinical findings, confirming the effectiveness of the proposed algorithm. By emphasizing the structural aspect of bone adaptation, the proposed algorithm brings a fresh perspective on bone adaptation at the peri-prosthetic bone. This method can help researchers and clinicians to improve implant designs for better clinical outcomes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Periodontitis is a common oral disease mainly caused by bacterial infection and inflammation of the gingiva. In the prevention or treatment of periodontitis, anti-bacterial agents are used to inhibit pathogen growth, despite increasing levels of bacterial resistance. Sapindus mukorossi Gaertn (SM) seed oil has proven anti-bacterial and anti-inflammation properties. However, the possibility of using this plant to prevent or treat periodontitis has not been reported previously. The aim of this study was to evaluate the effects of SM oil on experimental periodontitis in rats by using micro-CT and microbiota analysis. The distance between cementoenamel junction (CEJ) and alveolar bone crest (ABC) on the sagittal micro-CT slide showed that total bone loss (TBL) was significantly lower in CEJ-ABC distances between SM oil and SM oil-free groups on Day 14. Histology data also showed less alveolar bone resorption, a result consistent result with micro-CT imaging. The microbiota analyzed at phylum and class levels were compared between the SM oil and SM oil-free groups on Day 7 and Day 14. At the phylum level, Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria were the dominant bacterium. Firmicutes in box plot analysis was significantly less in the SM oil group than in the SM oil-free group on Day 7. At the class level, Bacteroidia, Gammaproteobacteria, Bacilli, Clostridia, and Erysipelotrichia were the dominant bacteria. The bacteria composition proportion of Bacilli, Clostridiay, and Erysipelotrichia could be seen in the SM oil group significantly less than in t SM oil-free group on Day 7. Overall, the present results show that topical application of SM oil can reduce bone resorption and change bacteria composition in the ligature-induced periodontitis model. According to these results, it is reasonable to suggest SM oil as a potential material for preventing oral disease. [ABSTRACT FROM AUTHOR]

Purpose: Diabetes Mellitus (DM) is a systemic disease that can effect tissues and their physiological functions at molecular and biochemical levels. Diabetic osteoporosis is one of the chronic diseases of bone metabolism effected by and characterized by augmented risk of osteoporotic fractures and destroying of bone microarchitecture. It was aimed to investigate the alterations in femoral bone structure that may take place as a complication of DM by using the antioxidant properties of eugenol and quercetin, which are phenolic compounds, in streptozotocin nicotinamide (STZ-NA) induced rats as an experimental type 2 DM (T2 DM) model. Methods: The antioxidant effect of eugenol and quercetin in case of DM development was determined by GSH ELISA kit. The effect of DM on alterations in bone structure was analyzed by micro CT. BMD, Tb.Bv/Tb.Tv, Tb.N, Tb.Th, Ct.Th, Tb.Sp and SMI data were calculated with the software CTAn. Results: Serum GSH levels, Tb.Th and Tb.Bv/Tb.Tv values statistically decreased, and SMI values statistically increased in diabetic group compared with controls. Serum GSH levels in eugenol group were higher than diabetic group, and Tb.Bv/Tb.Tv values in eugenol group were lower than controls. Quercetin group had higher serum GSH levels and Tb.Th values compared with diabetic group, while SMI values were lower in quercetin group compared with diabetic group. Conclusion: Eugenol and quercetin were revealed to have antioxidant, antidiabetic and osteoprotective effects on the repair of bone structure in experimental STZ-NA T2 DM model. [ABSTRACT FROM AUTHOR]

The combination of a bone and an implant surface is a dynamic biological process. By improving the osseointegration efficiency of the bone tissue around the implant surface, the implant can obtain long-term stability. In this study, we have investigated the potential applications of dual-wavelength lasers (Er:YAG laser and Nd:YAG laser) in implantations and observed their possible efficacy in promoting tissue repair around the implant. The animal experimental model of a rabbit femoral defect implant was used to simulate the process of tissue reconstruction around the implant in humans. The results indicated that by micro-CT observation, it was obvious that the bone mineral density (BMD) values of the dual-wavelength laser group were significantly higher than those of other groups. Furthermore, VG staining clearly showed that there was no obvious physiological gap detected between the implant and the surrounding bone tissues in the dual-wavelength laser group. HE staining further revealed that no significant influx of inflammatory cells was observed around the implants. Immunohistochemical staining of OCN and VEGF showed that the positive area percentages of the dual-wavelength laser group were significantly higher than other groups at the same time point. Therefore, the application of a dual-wavelength laser in implantations can exhibit a positive effect on promoting the reconstruction of bone tissues.

To observe the effect of black sesame oil lecithin solution on bone metabolism in naturally grown aging mice and compare with vitamin E.8-month-old SPF Kunming mice were randomly divided into normal saline group (NS group),vitamin E group (VE group),black sesame oil group (Oil group).The experiment lasted for 10 weeks.At the end of the experiment,the mice were sacrificed.The right femurs were taken for Micro CT scan,and the left ulna for bone component content determination.Compared with the NS group,the bone calcium and bone magnesium contents in the Oil group were significantly increased,and the SMI was significantly reduced,while BV/TV,Density and Conn-Dens were increased,but the difference was not statistically significant; compared with the VE group,The content of bone calcium and bone magnesium in the Oil group were significantly increased; the three-dimensional map showed that the bone trabeculae were arranged evenly and tightly,with small gaps and good continuity.After 10 weeks of naturally-growing old mice given black sesame oil,the bone mass and microstructure of the femur of the mice increased,suggesting the potential applications for anti-osteoporosis.

Introduction: About 1 in 11 Americans will experience a kidney stone, but underlying causes remain obscure. The objective of the present study was to separate idiopathic calcium oxalate stone formers by whether or not they showed positive evidence of forming a stone on Randall's plaque (RP). Materials and Methods: In patients undergoing either percutaneous or ureteroscopic procedures for kidney stone removal, all stone material was extracted and analyzed using micro-CT imaging to identify those attached to RP. Twenty-four-hour urine samples were collected weeks after the stone removal procedure and patients were off of medications that would affect urine composition. The endoscopic video was analyzed for papillary pathology (RP, pitting, plugging, dilated ducts, and loss of papillary shape) by an observer blinded to the data on stone type. The percent papillary area occupied by RP and ductal plugging was quantified using image analysis software. Results: Patients having even one stone on RP (N = 36) did not differ from non-RP patients (N = 37) in age, sex, BMI, or other clinical characteristics. Compared with the non-RP group, RP stone formers had more numerous, but smaller, stones, more abundant papillary RP formation, and fewer ductal plugs, both by quantitative measurement of surface area (on average, three times more plaque area, but only 41% as much plug area as in non-RP patients) and by semiquantitative visual grading. Serum and blood values did not differ between RP and non-RP stone formers by any measure. Conclusions: Growth of many small stones on plaque seems the pathogenetic scheme for the RP stone-forming phenotype, whereas the non-RP phenotype stone pathogenesis pathway is less obvious. Higher papillary plugging in non-RP patients suggests that plugs play a role in stone formation and that these patients have a greater degree of papillary damage. Underlying mechanisms that create these distinctive phenotypes are presently unknown. [ABSTRACT FROM AUTHOR]

BACKGROUND: There are many factors in the pathological process of osteoarthritis, including synovial inflammation, cartilage loss, subchondral bone damage, bone hyperplasia and so on. The specific mechanism is not yet clear. Micro CT is a non-destructive imaging tool, which can form high-resolution 3D images of samples, and realize the research of related structures and functions of bone and cartilage, quantitative evaluation of disease progression and treatment, and contrast-enhanced soft tissue imaging. Micro CT scanning of osteoarthritis animal model can clarify the pathological changes of joints, articular cartilage, subchondral bone, synovium, blood vessels and other tissues in the course of osteoarthritis, which is conducive to the study of the pathological progress of osteoarthritis. OBJECTIVE: To summarize the imaging methods and research prospects of micro CT in joints, cartilage, subchondral bone, synovium and intraosseous vessels of osteoarthritis animal model, so as to provide a new method for the study of the pathological mechanism of osteoarthritis. METHODS: By searching the databases of CNKI, Web of Science, Embase, PubMed and Wanfang, the Chinese and English keywords were “osteoarthritis, micro CT, pathology”. The qualified articles with strong correlation and relatively new publication years were selected for review. RESULTS AND CONCLUSION: (1) Micro CT has good imaging performance in joints, cartilage, subchondral bone, and intraosseous vessels. The imaging method is mature, which changes the shortcomings of traditional pathological sections on destroying tissue integrity and cumbersome steps. (2) Micro CT has not been reported in the literature on the imaging of synovium, but it has a good performance in the imaging of soft tissues, such as fat and tumor. The imaging of synovium has a research prospect in the future. (3) Micro CT can carry out three-dimensional reconstruction of specimens, break through the limitations of conventional two-dimensional pathological sections, and provide a new model for the study of the pathological mechanism of osteoarthritis. [ABSTRACT FROM AUTHOR]

A bone scaffold added to the dental alveolus immediately after an extraction avoids bone atrophy and deformity at the tooth loss site, enabling rehabilitation with implants. Photobiomodulation accelerates bone healing by stimulating blood flow, activating osteoblasts, diminishing osteoclastic activity, and improving the integration of the biomaterial with the bone tissue. The aim of the present study was to evaluate the effect of photobiomodulation with LED at a wavelength of 850 nm on bone quality in Wistar rats submitted to molar extraction with and without a bone graft using hydroxyapatite biomaterial (Straumann® Cerabone®). Forty-eight rats were distributed among five groups (n = 12): basal (no interventions); control (extraction) (basal and control were the same animal, but at different sides); LED (extraction + LED λ = 850 nm); biomaterial (extraction + biomaterial), and biomaterial + LED (extraction + biomaterial + LED λ = 850 nm). Euthanasia occurred at 15 and 30 days after the induction of the extraction. The ALP analysis revealed an improvement in bone formation in the control and biomaterial + LED groups at 15 days (p = 0.0086 and p = 0.0379, Bonferroni). Moreover, the LED group had better bone formation compared to the other groups at 30 days (p = 0.0007, Bonferroni). In the analysis of AcP, all groups had less resorption compared to the basal group. Bone volume increased in the biomaterial, biomaterial + LED, and basal groups in comparison to the control group at 15 days (p < 0.05, t-test). At 30 days, the basal group had greater volume compared to the control and LED groups (p < 0.05, t-test). LED combined with the biomaterial improved bone formation in the histological analysis and diminished bone degeneration (demonstrated by the reduction in AcP), promoting an increase in bone density and volume. LED may be an important therapy to combine with biomaterials to promote bone formation, along with the other known benefits of this therapy, such as the control of pain and the inflammatory process. [ABSTRACT FROM AUTHOR]

We understand heterogeneous‐explosive detonation only to the extent that we can first measure the salient chemical and microstructural features. Barring an inordinate amount of trial and error, we can tailor the detonation properties of our HE formulations only to the extent that we understand (at least qualitatively) the same effects. As an insensitive high explosive, 1, 3, 5‐triamino‐2, 4, 6‐trinitrobenzene (TATB) burns more heterogeneously than conventional high explosives, making its detonation properties sensitive to microstructure. The Benziger route can produce various grain morphologies depending on the amount of water used in the amination step. So‐called dry‐aminated (DA) TATB crystals are riddled with a void structure called wormholes, which are washed out ammonium chloride (NH4Cl) inclusions that form during synthesis. So‐called wet‐aminated (WA) TATB crystals do not contain NH4Cl inclusions but possess a very convoluted external structure. Using both micro and nano‐scale CT, we explore three DA‐TATB lots that reflect evolutionary processing changes, plus one WA‐TATB material. Micro CT imaged crystal collections show the exterior grain structure, revealing its roughness and providing a crude particle size measurement. The DA‐TATB lots that test most sensitively in the LANL ECOT corner‐turning test are roughest, having the appearance of being "corroded". Nano‐scale CT reveals both internal NH4Cl inclusions and void structures. The DA‐TATB lots that tested intermediate and high sensitivity in ECOT exhibited similar wormhole structures, which were more extensive than that of the low‐sensitivity lot. The least sensitive DA‐TATB lot also retained more NH4Cl, consistent with reduced connectivity of voids to the surface. [ABSTRACT FROM AUTHOR]

Background/Aim: The aim of this study was to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) on bone metabolism during the healing period in rat tibiae bone defects using micro--computed tomography (micro CT) imaging for three-dimensional morphological evaluation. Materials and Methods: The right tibia received ultrasound exposure (US group) every day, whereas the opposite side served as a control (Control group). At 1, 2, and 3 weeks after the operation, micro CT was performed, and the volume and surface area of new bone formation in the bone defects was evaluated three-dimensionally. Results: Bone volume (BV) and bone surface (BS) in the tibiae of both the US and Control groups demonstrated the highest values 1 week after the operation, with no significant differences between the groups. At 2 weeks after the operation, the BV and BS values in both groups had decreased, but the decrease was smaller in the US group than the Control group. At 3 weeks after the operation, the BV and BS values in the Control group were significantly lower than those in the US group. Conclusion: LIPUS stimulation can prevent bone loss during the healing of bone defects. [ABSTRACT FROM AUTHOR]

Jackstone calculi, having arms that extend out from the body of the stone, were first described over a century ago, but this morphology of stones has been little studied. We examined 98 jackstones from 50 different patient specimens using micro-computed tomography (micro CT) and infrared (IR) spectroscopy. Micro CT showed that jackstone arms consisted of an X-ray lucent core within each arm. This X-ray lucent core frequently showed sporadic, thin layers of apatite arranged transversely to the axis of the arm. The shells of the jackstones were always composed of calcium oxalate (CaOx), and with the monohydrate form the majority or sole mineral. Study of layering in the shell regions by micro CT showed that growth lines extended from the body of the stone out onto jack arms and that the thickness of the shell covering of jack arms often thinned with distance from the stone body, suggesting that the arms grew at a faster radial rate than did the stone body. Histological cross-sections of decalcified jackstone arms showed the core to be more highly autofluorescent than was the CaOx shell, and immunohistochemistry showed the core to be enriched in Tamm-Horsfall protein. We hypothesize that the protein-rich core of a jack arm might preferentially bind more protein from the urine and resist deposition of CaOx, such that the arm grows in a linear manner and at a faster rate than the bulk of the stone. This hypothesis thus predicts an enrichment of certain urine proteins in the core of the jack arm, a theory that is testable by appropriate analysis. [ABSTRACT FROM AUTHOR]

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Manufacturing defects, heterogeneous microstructure, and micro-segregation of secondary laves phases are the major issues to be resolved during the fabrication of alloy Inconel 718 (IN718) fabrication through metal additive manufacturing (AM). The present study delivers the importance of post AM double aging heat treatment (HT) of alloy IN718 fabricated through laser-based powder bed fusion process (L-PBF). Initially, the as-built IN718 sample was subjected to solution annealing at 980 °C for the duration of 1 hour followed by air cooling. Then, the L-PBF sample was subjected to double aging at 720 °C for 8 hours followed by furnace cooling to 620 °C in 2 hours. The specimen was kept at 620 °C for 8 hours and then cooled to room temperature. The beneficial influence of HT on the closure of AM-induced manufacturing defects such as pores and voids, microstructural changes, and microhardness have been reported. As-built microstructure showed the presence of heterogeneous columnar dendrites along the build direction with the presence of a large number of laves phases in the interdendritic regions. HT microstructure resulted in the formation of homogeneous austenite gamma (γ) matrix in which the strengthening phases such as gamma prime (γ′) (Ni3 (Al, Ti)) and gamma double prime (γ″) (Ni3Nb) were observed. As a result of HT, laves phases ((Ni, Fe, Cr)2·(Nb, Mo, Ti)) were dissolved in the grain interiors and precipitated in the grain boundaries as delta (δ) phase (NbNi3). The δ phase in the grain boundaries arrested the grain boundary dislocation, as well as grain growth, and revealed the relatively finer and homogenous grain structures. Further, a Micro-computed tomography (micro CT) examination revealed the absence of AM-induced pores after HT. The hardness of the heat-treated samples was increased to 35% and it showed an increase in hardness from 417 to 564 HV. Dimensional analysis was performed on the alloy IN718 to study the effect of thermal loading. The volumetric shrinkage of 3.084% was noted as a result of heat treatment at the micron-scale. [ABSTRACT FROM AUTHOR]

Objective: to determine the presence of marginal bacterial microfiltration in the IAI in different implant/abutment systems, in vitro. Material and methods: Fifty‐six implants from seven different brand names, 4 with cone and 3 with straight connections were used, implant and abutment were connected using the Ncm tightening as indicated by each of the manufacturers and then were sealed. The samples were subjected occlusal load and thermal cycling, a first sample of each group was observed by micro CT and in a second sample (both samples randomly selected) length of connection was measured, while the rest of the samples were mounted on devices according to the bacterial microfiltration model with Porphyromonas gingivalis. Results: Two of the conical connection system groups did not present bacterial microfiltration, one of the three straight connection groups only microfiltered in one sample, while the other two conical as well as the two straight connection samples showed different and important levels of bacterial microfiltration, all groups presented a direct relationship between the implant‐abutment adjustment determined by micro‐CT and bacterial microfiltration levels, not related to the connection length. Conclusion: Only two conical connection systems presented no bacterial microfiltration. [ABSTRACT FROM AUTHOR]

Liquid Composite Molding (LCM) is one of the widely used manufacturing techniques for high performance composite parts. In a simple LCM process, a pressurized liquid resin is injected inside a mold containing fibrous reinforcements. In order to create quality components using LCM processes, reinforcement characterization such as permeability and compaction response need to be performed fast and accurately. In this work, a micro CT based experimental-numerical reinforcement compaction and permeability characterization framework has been proposed which can potentially reduce process characterization cost by lowering material consumption and labor time and effort. The framework is non-destructive in nature and uses a miniaturized compression stage that can be housed in an X-ray computed tomography (XCT) system. This in-situ XCT experimental set-up is used to acquire the stress relaxation curve and XCT images of the reinforcement internal structure at multiple fiber volume fractions which are then converted into digital twins of the reinforcements. The virtual permeability of the reinforcement digital twin is computed through numerical flow simulations using realistic voxel models extracted from the stack of XCT images. The proposed approach has the capability of obtaining a plethora of information about the preform including, compaction response, statistical measurements of the internal preform geometry, and voxel models for numerical simulations. The methodology has been successfully demonstrated using two carbon fiber reinforcements with 3D woven architecture. The virtual permeability predictions were benchmarked against experimentally measured values, and were found to be in excellent agreement with the experimental data.

Heap leaching is a widely used solution mining technology that enables various kinds of low-grade ores to be processed economically. The solution flow characteristics are very important factors in the leaching process, and they influence both the overall recovery and kinetics of the system. The properties of fluid flow in porous media are associated with the pore structure, which is influenced by the grain size and shape. To study the influence of ore particle size gradation on the pore structure of the heap leaching system, a micro-CT scanning test was conducted in ore columns with two grain size gradation types, and images of the internal structure of the leaching columns were obtained. A 3D digital pore model of the two leaching columns was then established, and the spatial distribution characteristics of 2D and 3D porosity were analyzed. The pore network models of the two columns were then extracted from the reconstructed 3D binary pore structures using the maximal ball fitting method, and the effect of the ore particle size distribution on the pore throat radius, throat length, pore throat volume, shape factor, and coordination number was analyzed. The results show that the porosity of the column comprising well-graded ore particles is lower than the column with uniformly graded grains. In addition, the 2D and 3D porosities of the well-graded ores show a relatively high degree of heterogeneity compared to those of the more uniformly graded ores. The ore particle size gradation has a significant influence on pore size and pore connectivity, but it has a minimal influence on the pore throat shape factor. The number of large pores increases with a decrease in the amount of fine ore, and the pore throat radius, throat length, and pore throat volume also correspondingly increase. When the uniformity of ore particle gradation is enhanced, the proportion of isolated pores decreases and the proportion of the number of high coordination pores increases.

Introduction: Micro-CT scanner with a resolution of about 5 micrometers is one of the modalities used to create three-dimensional/two-dimensional images of urinary stones. This study aimed to optimize imaging parameters in micro-computed tomography (CT) scanner based on the signal-to-noise ratio (SNR) of urinary stones for the analysis of stone composition. Material and Methods: In this study,eight micro-CT scanning protocols were applied to five urinary stones taken from different patients. Each scanning protocol had different voltage, current, and exposure parameters. The reconstructed images were then analyzed based on image brightness and SNR. The optimized imaging parameters which were chosen were that having high SNR because the high-quality image has high SNR. Results: The results showed that two groups of urinary stones had the same mean Hounsfield Units (HU) value in the third scanning protocols (i.e., 65 kV, 123 µA, and 850 ms). Mean HU values in group one (i.e., stones numbered 1, 3, and 4) were reported as 790, 760, and 720, respectively. The second group (i.e., stones numbered 2 and 5) had mean HU values of -514 and -343, respectively. The imaging parameters (i.e., 75 kV, 106 µA, and 600 ms) had high SNR (25-34) for the first group. The SNR (12.8-13.25) was for the second group at imaging parameters (i.e., 85 kV, 94 µA, and 500 ms). Conclusion: Based on the SNR, the two optimal imaging parameters for the first and second groups were reported as 75 kV, 106 µA, and 600 ms, as well as 85 kV, 94 µA, and 500 ms, respectively.

In this paper, a nano Voxel X-ray 3D microscope is used to scan the long flame coal samples and to reconstruct the 3D pore structure by the use of microscopic computed tomography. With image segmentation technique, a model of micro-pore structure of coal is obtained from the reconstructed coal. With different planes selected as seepage inlets, a numerical simulation of low-pressure water seepage is conducted. Studies show that water pressure gradually decreases along the direction of water seepage and reaches the maximum at the pore-pipes with good connectivity near the inlet. Due to the difference between the structure and development direction of pores in the three dimensions, there is an optimal seepage outlet that is most appropriately corresponding to each seepage inlet. When different planes are selected as seepage inlets, the velocity of each seepage outlet is positively correlated with the seepage mass flow rate at the outlet.

Objectives: The aims of this clinical study were to compare internal three-dimensional (3D) adaptation of porcelain laminate veneers (PLV) with minimal tooth preparation and without tooth preparation (prepless) and to evaluate the clinical outcomes at baseline and following 6, 12, and 24 months after luting. Method and Materials: Thirty-one prepless PLV and 31 PLV with minimal tooth preparation were fabricated using lithium disilicate glass-ceramic material and placed in 12 patients (8 women, 4 men; 18 to 40 years old). All PLV were luted with an adhesive luting system (Variolink veneer). A silicone replica was obtained to measure internal adaptation of each PLV using a low viscosity polyvinyl siloxane impression material just before luting. Silicone replicas were scanned in x-ray micro computerized tomography (micro CT). Clinical evaluations took place at baseline (2 days after luting) and following 6,12, and 24 months after luting. Marginal integrity, marginal discoloration, secondary caries, tooth sensitivity, and fracture were evaluated following FDI criteria. Replica scores were analyzed using Mann-Whitney U and Student's t test (α = .05). Kaplan-Meier statistical analysis was done for the survival rate of PLV. FDI criteria scores were analyzed using Pearson's chi-square test (α = .05). Results: The median marginal gaps for PLV-without-tooth-preparation and PLV-with-minimal-tooth-preparation groups were 100 urn and 140 µm respectively. There was a statistically significant difference between the two groups with respect to marginal gap (P = .04). The mean internal adaptation for the PLV-without-tooth-preparation group was 217.17 ±54.72 µm, and was 170.67 ±46.54 µm for the PLV-with-minimal-tooth-preparation group. There was a statistically significant difference between the two groups (P = .001). Based on FDI criteria, 100% of the PLV were rated satisfactory during the 2-year period. Conclusions: In this in-vivo study, mean and median values of marginal gap and internal adaptation for PLV with minimal tooth preparation and PLVs without tooth preparation were within a clinically acceptable range. A 100% success rate was recorded for all PLV during the 2-year period. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) in an intricate disorder characterized by reproductive and metabolic abnormalities that may affect bone quality and strength along with the lifespan. The present study analysed the impact of postnatal androgenization (of a single dose of testosterone propionate 1.25 mg subcutaneously at day 5 of life) on bone development and markers of bone metabolism in adult female Wistar rats. Compared with healthy controls, the results of measurements of micro-computed tomography (microCT) of the distal femur of androgenized rats indicated an increased cortical bone volume voxel bone volume to total volume (VOX BV/TV) and higher trabecular number (Tb.n) with reduced trabecular separation (Tb.sp). A large magnitude effect size was observed in the levels of circulating bone formation Procollagen I N-terminal propeptide (P1NP) at day 60 of life; reabsorption cross-linked C-telopeptide of type I collagen (CTX) markers were similar between the androgenized and control rats at days 60 and 110 of life. The analysis of gene expression in bone indicated elements for an increased bone mass such as the reduction of the Dickkopf-1 factor (Dkk1) a negative regulator of osteoblast differentiation (bone formation) and the reduction of Interleukin 1-b (Il1b), an activator of osteoclast differentiation (bone reabsorption). Results from this study highlight the possible role of the developmental programming on bone microarchitecture with reference to young women with PCOS. [ABSTRACT FROM AUTHOR]

The aim is to assess the influence of fabrication techniques—conventional (CN), CAD-CAM (CC), and 3D printing (3D)—on the marginal fit, adaptation, surface roughness, and wear of interim restorations of crowns. Thirty interim crowns were fabricated using CN, CC, and 3D techniques. Sixty discs were fabricated to evaluate surface wear and surface roughness properties, with 10 disc samples in each group (n = 10). Internal adaptation and marginal integrity of interim crowns were analyzed with micro CT to detect microgaps at selected points. Average surface micro-roughness (Ra) was calculated in micrometers (μm) using an optical non-contact surface microscope under cyclic loading. Surface wear was evaluated by surface area measurements (mm3) using a micro CT. Analysis of variance (ANOVA) and Tukey's post hoc comparison tests with Pearson correlation were performed for data analysis. The highest adaptation means were for CN (269.94 ± 64 μm), and the lowest mean value was observed for 3D (197.82 ± 11.72 μm) crowns. CN and CC specimens showed comparable adaptation (p > 0.05), which were significantly higher (p < 0.05) than 3D crowns. CN crowns showed significantly higher marginal misfit compared to 3D (p < 0.05) and CC (p < 0.05) crowns. The highest mean surface roughness was observed in the 3D crowns (5.61 ± 0.33 µm), whereas the lowest was found in CC crowns (3.28 ± 0.34 µm). Better restoration Ra was observed using the CC method followed by CN. CN had the highest wear (17.79 ± 2.78 mm3), and the lowest wear was observed in the 3D (10.81 ± 2.00 mm3) specimen. Low surface wear was observed using 3D printing, followed by CN and CC techniques. The printed specimen showed comparable outcomes to CAD-CAM restoration; however, they were better than CN restoration. A positive correlation between adaptation and surface roughness was observed, indicating an effect of the fabrication technique on material physical property. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to determine the better protein for supporting optimal linear growth, as the exact composition and benefits of specific dietary proteins in supporting linear growth is unknown. In the current study, we compared the effect of soy and whey proteins, both proteins contain all essential amino acids and are considered the best proteins in their categories. Young male rats were subjected to multiple feeding protocols using iso-energetic diets containing soy or whey as the sole protein source. The rats were allowed to eat ad libitum for 11, 24, or 74 days in the first set of experiments, and the soy group was pair-fed to the whey group in the second set. The differences in weight gain, food consumption, and humeri length of the soy group that were greater at the beginning of the ad libitum experiments lessened over time. Pair-fed experiments revealed that the increased weight and humeri length resulted from the differences in food consumption. However, other parameters were protein specific. Bone quality, which was better in the soy group at 24 days, was matched by the whey group and even surpassed that of the soy group in the long-term experiment, with a significantly greater bone mineral density, cortical thickness, and growth plate. Although in the short term the levels of insulin like growth factor (IGF)-I were similar between the groups, IGF-I increased with age in the whey group, and the levels at the long-term experiment were significantly higher compared to the soy group. Furthermore, using the pair fed setup made it clear that when the difference in food consumption were no longer playing part, whey was more efficient in increasing IGF-I. There were no indications of metabolic sequelae. Although the use of soy is gaining in popularity as a sustainable protein, our findings indicate a better effect of whey on linear growth by leading to slower growth with better-organized epiphyseal growth plates and bone quality.

Vascular calcification, a common pathological phenomenon in atherosclerosis, diabetes, hypertension, and other diseases, increases the incidence and mortality of cardiovascular diseases. Therefore, the prevention and detection of vascular calcification play an important role. At present, various techniques have been applied to the analysis of vascular calcification, but clinical examination mainly depends on non-invasive and invasive imaging methods to detect and quantify. Computed tomography (CT), as a commonly used clinical examination method, can analyze vascular calcification. In recent years, with the development of technology, in addition to traditional CT, some emerging types of CT, such as dual-energy CT and micro CT, have emerged for vascular imaging and providing anatomical information for calcification. This review focuses on the latest application of various CT techniques in vascular calcification.