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Contractions of the uterus play an important role in menstruation and fertility, and contractile dysfunction can lead to chronic diseases such as endometriosis. However, the structure and function of the uterus are difficult to interrogate in humans, and thus animal studies are often employed to understand its function. In rats, anatomical studies of the uterus have typically been based on histological assessment, have been limited to small segments of the uterine structure, and have been time‐consuming to reconstruct at the organ scale. This study used micro‐computed tomography imaging to visualise the muscle structures in the entire non‐pregnant rat uterus and assess its use for 3D virtual histology. An assessment of the rodent uterus is presented to (i) quantify muscle thickness variations along the horns, (ii) identify predominant fibre orientations of the muscles and (iii) demonstrate how the anatomy of the uterus can be mapped to 3D volumetric meshes via virtual histology. Micro‐computed tomography measurements were validated against measurements from histological sections. The average thickness of the myometrium was found to be 0.33 ± 0.11 mm and 0.31 ± 0.09 mm in the left and right horns, respectively. The micro‐computed tomography and histology thickness calculations were found to correlate strongly at different locations in the uterus: at the cervix, r = 0.87, and along the horn from the cervical end to the ovarian end, respectively, r = 0.77, r = 0.89 and r = 0.54, with p < 0.001 in every location. This study shows that micro‐computed tomography can be used to quantify the musculature in the whole non‐pregnant uterus and can be used for 3D virtual histology. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the effect of remineralization agents such as fluoride varnish and P11-4, alone and in combination with Er: YAG laser, on in-vitro hard tissue repair in artificial enamel lesions. Materials and methods: A total of sixty enamel surfaces of 4 × 5 mm in size were created on both the buccal and lingual sides of thirty extracted wisdom teeth. Remineralization agents were applied to the specimens that were grouped as follows: Group 1, control; Group 2, fluoride varnish (FV); Group 3, P11-4; Group 4, laser; Group 5, laser + FV; and Group 6, laser + P11-4. The fluorescence level was determined with DiagnoDent. The enamel mineral density, area and volume, and caries lesion area and volume were determined with micro-computed tomography (µCT), surface features were evaluated using scanning electron microscopy (SEM), and elemental analysis was performed using energy dispersive x-ray spectroscopy (EDS). Results: For specimens treated only with self-assembling peptide P11-4, the caries lesion area (mm2) values were 38.19 and 21.62, and the caries lesion volume (mm3) values were 6.27 and 2.99, respectively for pre- and post-treatment. In combination usage of self-assembling peptide P11-4 and laser, the caries lesion area (mm2) values were 38.39 and 16.91, and the caries lesion volume (mm3) values were 11.15 and 3.64, respectively for pre- and post-treatment. In the application of the P11-4 alone and in combination with laser, there was a statistically significant decrease in DiagnoDent values, an increase in enamel volume(mm3),enamel area(mm2) and mineral density(g/cm3) values and a decrease in caries lesion volume(mm3) and area(mm2) obtained by µCT, and an increase in %Ca and %F values obtained by SEM/EDS analysis (p < 0.05). It was discovered that the samples treated with P11-4 had a considerably higher rise in the Ca/P ratio than the samples treated with FV (p < 0.05). The calcium content increased significantly more when P11-4 application was combined with laser irradiation (p < 0.05). Conclusions: The combined use of self-assembling peptide P11-4 and laser accelerated the remineralization process and increased the remineralization capacity. Clinical relevance: FV and P11-4, alone or in combination with laser, can be successfully used as remineralization agents in initial enamel caries. [ABSTRACT FROM AUTHOR]

This research aims to detect and analyze critical internal and surface defects in metal components manufactured by powder bed fusion of metals using a laser beam (PBF‐LB/M). The aim is to assess their impact on the fatigue behavior. Therefore, a combination of methods, including image processing of micro‐computed tomography (μCT) scans, fatigue testing, and machine learning, was applied. A workflow was established to contribute to the nondestructive assessment of component quality and mechanical properties. Additionally, this study illustrates the application of machine learning to address a classification problem, specifically the categorization of pores into gas pores and lack of fusion pores. Although it was shown that internal defects exhibited a reduced impact on fatigue behavior compared with surface defects, it was noted that surface defects exert a higher influence on fatigue behavior. A machine learning algorithm was developed to predict the fatigue life using surface defect features as input parameters. Highlights: Established workflow for extracting surface and internal features.Developed pore classification ML algorithm with 92.4% accuracy.Effectively developed ML algorithm for predicting fatigue life. [ABSTRACT FROM AUTHOR]

The femoral head is one of the most commonly used bones for allografts and biomechanical studies. However, there are few reports on the trabecular bone microarchitectural parameters of freshly harvested trabecular bones. To our knowledge, this is the first study to characterize the microstructure of femoral heads tested immediately after surgery and compare it with the microstructure obtained with conventional freezing. This study aims to investigate whether freezing at −80 °C for 6 weeks affects the trabecular microstructure of freshly harvested bone tissue. This study was divided into two groups: one with freshly harvested human femoral heads and the other with the same human femoral heads frozen at −80 °C for 6 weeks. Each femoral head was scanned using an X-ray microcomputed tomography scanner (µCT) to obtain the microarchitectural parameters, including the bone volume fraction (BV/TV), the mean trabecular thickness (Tb.th), the trabecular separation (Tb.sp), the degree of anisotropy (DA), and the connectivity density (Conn.D). There was no statistically significant difference between the fresh and the frozen groups for any of the parameters measured. This study shows that freezing at −80 °C for 6 weeks does not alter bone microstructure compared with freshly harvested femoral heads tested immediately after surgery. [ABSTRACT FROM AUTHOR]

Background: The existence of voids within the mineral trioxide aggregate (MTA) composition is one of the factors that can influence the treatment outcome. The primary objective of this study was to quantitatively assess and compare the MTA orthograde obturation quality in severe curved root canals using two different MTA compaction techniques: manual compaction with K-file, or Auger technique using micro-computed tomography (micro-CT) imaging. Methods: For this study, 26 mandibular first molar teeth with severely curved mesiobuccal root canals were selected. These samples were randomly divided into two groups. All root canals were instrumented using ProTaper Gold rotary files up to the F3 file at the working length. In one group, OrthoMTA was compacted using a stainless steel K-file, while in the other group, the Auger technique was employed for compaction into the root canals. Once the MTA had completely set, the filled root canals were subjected to scanning using a high-resolution micro-CT scanner. The porosity volume was determined as a percentage in relation to the overal volume of the canal, and the collected data were subjected to analysis using SPSS software, with the significance level set at P < 0.05. Results: The two techniques had no significant difference in open, closed, and total mean porosity. In both groups, the mean of open porosity was significantly more than closed porosity. Conclusions: According to the results of the present study, neither of these two techniques is preferred to the other, and factors such as working time, etc., can be considered to choose the more appropriate clinical technique. [ABSTRACT FROM AUTHOR]

Chip formation is considered one important indicator to evaluate machining processes. In particular, geometric features of chips may provide important insights for the assessment of machining stability and productivity. In fixed-abrasive machining processes, such as grinding and honing, chips are simultaneously produced by many of the geometrically undefined cutting edges. Despite being "undefined," geometric features of abrasive grains can still be statistically characterized or described. Accordingly, it can be assumed that, under stable machining conditions, the geometric features of abrasive chips may also conform to certain statistical patterns. However, statistical characterization of abrasive chips can be very challenging due to their large quantity, irregular shapes, minuscule size, and sometimes tangled condition. In this study, an analysis method combining metallographic preparation and micro-computed tomography (micro-CT) has been developed to characterize abrasive chips produced by a honing stone. The results regarding the geometric characteristics of the obtained massive abrasive chips, i.e., their sizes and shapes, were presented and statistically described. It was found most chips had a size around 50 µm and the shape being a slightly elongated and curved cone. Most of the geometric features could meet a positive skewness distribution. [ABSTRACT FROM AUTHOR]

Aim: To assess the efficacy of heterologous fibrin biopolymer (HFB) in promoting alveolar bone healing after tooth extraction in rats. Materials and Methods: The upper right incisors of 48 Wistar rats were extracted. Toothless sockets were filled with HFB (HFBG, n = 24) or blood clot (BCG, n = 24). The tooth extraction sites were subjected to micro‐computed tomography (micro‐CT), histological, histomorphometric and immunohistochemical (for Runt‐related transcription factor 2/Runx2 and tartrate‐resistant acid phosphatase/TRAP) analyses on days 0, 7, 14 and 42 after extraction. Results: Socket volume remained similar between days 0 and 14 (69 ± 5.4 mm3), except in the BCG on day 14, when it was 10% lower (p =.043). Although the number of Runx2+ osteoblasts was high and similar in both groups (34 × 102 cells/mm2), the HFBG showed lower inflammatory process and osteoclast activity than BCG at 7 days. On day 14, the number of Runx2+ osteoblasts remained high and similar to the previous period in both groups. However, osteoclast activity increased. This increase was 55% lower in the HFBG than BCG. In the BCG, the presence of an inflammatory process and larger and numerous osteoclasts on day 14 led to resorption of the alveolar bone ridge and newly formed bone. On day 42, numbers of Runx2+ osteoblast and TRAP+ osteoclasts decreased dramatically in both groups. Although the BCG exhibited a more mature cortical bone formation, it exhibited a higher socket reduction (28.3 ± 6.67%) and smaller bone volume (37 ± 5.8 mm3) compared with HFBG (socket reduction of 14.8 ± 7.14% and total bone volume of 46 ± 5.4 mm3). Conclusions: HFB effectively suppresses osteoclast activity and reduces alveolar bone resorption compared with blood clot, thus preventing three‐dimensional bone loss, particularly during the early healing period. HFB emerges as a promising biopharmaceutical material for enhancing healing processes after tooth extraction. [ABSTRACT FROM AUTHOR]

This study assessed the ability of Twisted File Adaptive (TFA), TruNatomy (TRN) and VDW.Rotate (VR) instruments activated by continuous rotation (CR) and adaptive motion (AM) to shape curved root canals. Thirty mandibular molars with two separate mesial canals 20°–40° curved were collected and scanned using micro‐computed tomography (μCT). The canals were then randomly assigned into six groups (n = 10): TRN, VR or TFA instruments activated by CR or AM. TRN groups 17.02, 20.04 and 26.04; VR groups 15.04, 20.05 and 25.06; TFA groups were shaped consecutively using 15K‐file, 20.04 and 25.06. After they were shaped, the canals were scanned again. The volume of removed dentin, canal transportation and centring ratio were calculated μCT images. All data were analysed using the Kruskal–Wallis test or one‐way analysis of variance (p < 0.05). With both kinematics, the TRN instrument removed the least amount of dentin, the VR‐CR and the TFA‐AM removed the most (p < 0.05). The transportation and centring ratios among all groups were similar (p > 0.05). The volume of dentin removed, the diameter or design features of the instruments and different kinematics did not affect the centring ratio and the amount of transportation and remained within safe limits. All three instruments activated by either kinematics were found to have similar effectiveness in shaping curved root canals. [ABSTRACT FROM AUTHOR]

This study investigated the root canal morphology of fused‐rooted mandibular second molars based on the pulp chamber floor (PCF) and analysed the correlation between the external morphology of the radicular groove, and the internal morphology of the PCF and root canal configuration. A total of 291 fused‐rooted teeth collected from the Chinese population were scanned using micro‐computed tomography and a dental operating microscope was used for observing the PCFs. The classification of the PCF and root canal configuration were identified according to modified Min et al.'s and Gao et al.'s classifications, respectively. Additionally, a new radicular groove classification was proposed. The correlation among these morphological characteristics was investigated using the chi‐square test and Fisher's exact test (p < 0.05). The results showed that 74.2% of teeth had C‐shaped PCFs, while 21.0% had non‐C‐shaped PCFs. As for the root canal configurations, 37.5% of teeth were merging type, 40.9% were symmetrical type, and 14.8% were asymmetrical type. Statistical analysis revealed a significant correlation between the PCF types and the root canal configurations (p < 0.001). The dominant root canal types for teeth with C‐shaped PCFs were merging and symmetrical types, while the asymmetrical type was not identified in non‐C‐shaped PCFs. In addition, significant morphological association between the root canals and radicular grooves was also revealed (p < 0.001). Teeth with different PCF morphologies exhibit specific patterns of root canal category distribution. Understanding the morphological nuances of the root canal based on the PCF can assist clinicians in predicting and identifying the canal configuration beneath the visible orifice. [ABSTRACT FROM AUTHOR]

Aim Methodology Results Conclusion The present study investigated the influence of apical periodontitis (AP) on the severity of rheumatoid arthritis (RA) using a Wistar rat model.Forty male Wistar rats were distributed across four groups (n = 10) based on the induction of RA and AP: Control, RA, AP, and RA + AP. RA was induced through two immunisations with type II collagen emulsified in incomplete Freund's adjuvant, followed by one immunisation with complete Freund's adjuvant. After 21 days of RA induction, AP was induced by exposing the pulp of four molars. Animals were euthanized after 28 days of pulp exposure. Through the experiment, visual and behavioural assessments tracked RA development and the knees and hind paw joints were measured. Micro‐computed tomography scans of knees and hind paws, as well as mandibles and maxillae, were conducted to evaluate RA severity and the presence of AP, respectively. Serum samples were collected to analyse proinflammatory cytokines (IL‐1β, IL‐2, IL‐17, and TNF‐α). Non‐parametric data were analysed using the Kruskal‐Wallis test followed by Student–Newman–Keuls test, while one‐way anova followed by Tukey's test was performed for parametric data. A significance level of 5% was employed.All molars submitted to access cavity developed AP. All joints subjected to arthritis induction developed the disease, with AP + RA demonstrating a higher arthritis severity when compared to the RA group (p < .05). RA + AP group displayed a significantly larger hind paw and knee circumference compared to the RA group (p < .05). Micro‐CT images of RA and RA + AP groups revealed joints with erosions and bone deformities, with a significantly lower bone surface density, lower trabecular number and higher trabecular separation in the hind paw and a significantly lower percent bone volume and higher trabecular separation in the knees of RA + AP group compared to RA group (p < .05). RA + AP group exhibited a significantly higher level of TNF‐α and a lower level of IL‐2 compared to all other groups (p < .05). Both RA and RA + AP groups had significantly higher IL‐17 levels (p < .05), while there was no significant difference in IL‐1β levels among the groups (p > .05).The findings from this study underscore a possible relationship between apical periodontitis and the exacerbation of rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Pedipalps – chelate 'pincers' as the second pair of prosomal appendages – are a striking feature of scorpions and are employed in varied biological functions. Despite the distinctive morphology and ecological importance of these appendages, their anatomy remains underexplored. To rectify this, we examined the pedipalps of the Australian black rock scorpion, Urodacus manicatus , using a multifaceted approach consisting of microcomputed tomography, scanning electron microscopy, energy dispersive X-ray spectroscopy, and live pinch force measurements. In doing so, we document the following aspects of the pedipalps: (1) the musculature in three dimensions; (2) the cuticular microstructure, focusing on the chelae (tibial and tarsal podomeres); (3) the elemental construction of the chelae teeth; and (4) the chelae pinch force. We recognise 25 muscle groups in U. manicatus pedipalps, substantially more than previously documented in scorpions. The cuticular microstructure – endo-, meso-, and exocuticle – of U. manicatus pedipalps is shown to be similar to other scorpions and that mesocuticle reinforces the chelae for predation and burrowing. Elemental mapping of the chelae teeth highlights enrichment in calcium, chlorine, nickel, phosphorus, potassium, sodium, vanadium, and zinc, with a marked lack of carbon. These elements reinforce the teeth, increasing robustness to better enable prey capture and incapacitation. Finally, the pinch force data demonstrate that U. manicatus can exert high pinch forces (4.1 N), further highlighting the application of chelae in subduing prey, as opposed to holding prey for envenomation. We demonstrate that U. manicatus has an array of adaptions for functioning as a sit-and-wait predator that primarily uses highly reinforced chelae to process prey. [ABSTRACT FROM AUTHOR]

Objective Materials and Methods Results Conclusion To investigate the early impact of plaque accumulation in a buccal dehiscence defect on peri‐implant marginal bone resorption.In six male Mongrel dogs, four dental implants were placed in the posterior maxilla on both sides (two implants per side). Based on the group allocation, each implant was randomly assigned to one of the following four groups to decide whether buccal dehiscence defect was prepared and whether silk ligation was applied at 8 weeks post‐implant placement for peri‐implantitis induction: UC (no defect without ligation); UD (defect without ligation); LC (no defect with ligation); and LD (defect with ligation) groups. Eight weeks after disease induction, the outcomes from radiographic and histologic analyses were statistically analyzed (p < .05).Based on radiographs, the exposed area of implant threads was smallest in group UC (p < .0083). Based on histology, both the distances from the implant platform to the first bone‐to‐implant contact point and to the bone crest were significantly longer in the LD group (p < .0083). In the UD group, some spontaneous bone fill occurred from the base of the defect at 8 weeks after implant placement. The apical extension of inflammatory cell infiltrate was significantly more prominent in the LD and LC groups compared to the UC group (p < .0083).Plaque accumulated on the exposed implant surface had a negative impact on maintaining the peri‐implant marginal bone level, especially when there was a dehiscence defect around the implant. [ABSTRACT FROM AUTHOR]

For the first time, this paper explores the role of hydration kinetics on microcrack development in cement mortars using the μ-CT technique with a resolution of 2.2 µm. Three binders were tested: fine-grained ordinary Portland cement (OPC) with Blaine fineness of 391 m2/kg, coarse-grained OPC made from the same clinker with Blaine fineness of 273 m2/kg, and H-cement as a representative of the alkali-activated binder. It was found that most microcracks have a width in the range of 5–10 µm, increasing their occurrence with the progress of sealed hydration. While H-cement and coarse-grained OPC showed a comparable number of microcracks, fine-grained OPC exhibited more than twice the number of microcracks. In this sense, high hydration kinetics induce more microcracks, promoting later coalescence into visible cracks and disintegration of concrete at the end. Therefore, durable concrete with minimum microcracks should be derived from slow hydration kinetics or alkali-activation processes. [ABSTRACT FROM AUTHOR]

Subchondral bone remodeling, mediated by osteocytes within the lacuno-canalicular network, plays a crucial role in osteoarthritis (OA) progression. Following cell death, lacunae preserve integrity, offering insights into bone remodeling mechanisms. Limited and controversial data on osteocyte lacuna morphology in OA result from small sample sizes and two-dimensional (2D) techniques that have been used thus far. This study aimed to quantify three-dimensional (3D) osteocyte lacunar characteristics at well-defined tibial plateau locations, known to be differently affected by OA. Specifically, 11 tibial plateaus were obtained from end-stage knee-OA patients with varus deformity. Each plateau provided one sample from the less affected lateral compartment and two samples from the medial compartment, at minimum and maximum bone volume fraction (BV/TV) locations. High-resolution desktop micro-computed tomography (micro-CT) at 0.7 μm voxel resolution imaged the 33 samples. Lacuna number density (Lc.N/BV) and lacuna volume density (Lc.TV/BV) were significantly lower (p < 0.02) in samples from the medial side with maximum BV/TV compared to lateral side samples. In the medial compartment at maximum local BV/TV, mean lacuna volume (Lc.V), total lacuna volume (Lc.TV), and Lc.TV/BV were significantly (p < 0.001) lower than in the region with minimum BV/TV. Lc.N/BV was also significantly lower (p < 0.02) at the maximum local BV/TV location compared to the region with minimum BV/TV. Our findings suggest that subchondral bone lacunae adapt to the changing loads in end-stage OA. [ABSTRACT FROM AUTHOR]

Morphological species identification is the traditional way to identify species. More recently, biodiversity studies have depended on DNA barcoding for species identification. Mismatches between morphological and genetic species identification caused by voucher specimen misidentifications lead to ambiguous species identification. We used barnacles of the genera Amphibalanus and Balanus to investigate this issue. The purpose of this study was to assess the accuracy of the Barcoding of Life database and determine the true species affinity of three inconsistent barnacle barcode index numbers using an integrative taxonomic approach. To this end, we re-identified barcoded voucher specimens, or we identified specimens based on a dichotomous key that we barcoded subsequently. We found that 75% of Barcoding of Life clades representing genetic species showed inconsistent species assignments. One clade (BOLD: AAG0069), containing mostly unidentified Balanus sp. individuals, was morphologically and genetically Balanus balanus (Linneaus, 1758); a second clade (BOLD: AAB1410), containing specimens mostly identified as B. balanus , turned out to be morphologically and genetically Balanus crenatus Bruguière, 1789; and a third clade (BOLD: AAE2482), containing different species of Amphibalanus , was Amphibalanus improvisus (Darwin, 1854). This study showed that morphological species identification and taxonomic expertise can resolve the widespread misidentification in barcoding data. To prevent this problem in the future, morphological taxonomy and molecular species identification need to interact more closely. [ABSTRACT FROM AUTHOR]

Bone microdamage is common at subchondral bone (SCB) sites subjected to repeated high rate and magnitude of loading in the limbs of athletic animals and humans. Microdamage can affect the biomechanical behaviour of bone under physiological loading conditions. To understand the effects of microdamage on the mechanical properties of SCB, it is important to be able to quantify it. The extent of SCB microdamage had been previously estimated qualitatively using plain microcomputed tomography (μCT) and a radiocontrast quantification method has been used for trabecular bone but this method may not be directly applicable to SCB due to differences in bone structure. In the current study, SCB microdamage detection using lead uranyl acetate (LUA) and quantification by contrast‐enhanced μCT and backscattered scanning electron microscopy (SEM) imaging techniques were assessed to determine the specificity of the labels to microdamage and the accuracy of damaged bone volume metrices. SCB specimens from the metacarpus of racehorses, with the hyaline articular cartilage (HAC) removed, were grouped into two with one group subjected to ex vivo uniaxial compression loading to create experimental bone damage. The other group was not loaded to preserve the pre‐existing in vivo propagated bone microdamage. A subset of each group was stained with LUA using an established or a modified protocol to determine label penetration into SCB. The μCT and SEM images of stained specimens showed that penetration of LUA into the SCB was better using the modified protocol, and this protocol was repeated in SCB specimens with intact hyaline articular cartilage. The percentage of total label localised to bone microdamage was determined on SEM images, and the estimated labelled bone volume determined by μCT in SCB groups was compared. Label was present around diffuse and linear microdamage as well as oblique linear microcracks present at the articular surface, except in microcracks with high‐density mineral infills. Bone surfaces lining pores with recent mineralisation were also labelled. Labelled bone volume fraction (LV/BV) estimated by μCT was higher in the absence of HAC. At least 50% of total labels were localised to bone microdamage when the bone area fraction (B.Ar/T.Ar) of the SCB was greater than 0.85 but less than 30% when B.Ar/T.Ar of the SCB was less than 0.85. To adjust for LUA labels on bone surfaces, a measure of the LV/BV corrected for bone surface area (LV/BV BS−1) was used to quantify damaged SCB. In conclusion, removal of HAC and using a modified labelling protocol effectively stained damaged SCB of the metacarpus of racehorses and represents a technique useful for quantifying microdamage in SCB. This method can facilitate future investigations of the effects of microdamage on joint physiology. [ABSTRACT FROM AUTHOR]

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Abstract Background The existence of voids within the mineral trioxide aggregate (MTA) composition is one of the factors that can influence the treatment outcome. The primary objective of this study was to quantitatively assess and compare the MTA orthograde obturation quality in severe curved root canals using two different MTA compaction techniques: manual compaction with K-file, or Auger technique using micro-computed tomography (micro-CT) imaging. Methods For this study, 26 mandibular first molar teeth with severely curved mesiobuccal root canals were selected. These samples were randomly divided into two groups. All root canals were instrumented using ProTaper Gold rotary files up to the F3 file at the working length. In one group, OrthoMTA was compacted using a stainless steel K-file, while in the other group, the Auger technique was employed for compaction into the root canals. Once the MTA had completely set, the filled root canals were subjected to scanning using a high-resolution micro-CT scanner. The porosity volume was determined as a percentage in relation to the overal volume of the canal, and the collected data were subjected to analysis using SPSS software, with the significance level set at P

Objective: The aim of this study is to evaluate the effectiveness of 38% silver diamine fluoride (SDF) in preventing secondary caries formation by comparing it with other fluoride-containing remineralization agents such as sodium fluoride and titanium tetrafluoride in vitro.Material and Methods: Cavities of 4x2x2 mm were prepared on the mesial, distal, buccal and lingual surfaces of the extracted 12 intact human third molars. 38% silver diamine fluoride solution was applied to the first group, 2% NaF solution to the 2nd group, 2% TiF4 solution to the 3rd group and deionized water to the 4th group. After the solutions were applied, the cavities were restored with composite resin. Then, all samples were aged by thermal cycle method and sterilized by autoclave. The volume of the lesions formed by keeping the samples in 5% sucrose solution containing Streptococcus mutans and Lactobacillus acidophilus for 28 days was evaluated by micro computed tomography method. Data analysis of the study was performed using SPSS 21.0 V (IBM, Chicago, USA) statistical package program. Group results were compared using one-way analysis of variance (ANOVA) test (p>0.05). Results: Although the secondary caries lesion volume was found to be lower in the silver diamine fluoride applied group compared to the other groups, there was no statistically significant difference between the groups. Conclusion: These results show that the effectiveness of silver diamine fluoride to prevent secondary caries formation in composite resin restorations should be investigated with longer-term studies.

Significance: Leakage in the interfaces between restorative materials and tooth structure allows for fluid and bacterial acid infiltration, causing restoration failure due to secondary caries. Dentists spend more time replacing composite restorations than placing new ones. Previous in vitro and in vivo studies on enamel and root surfaces using shortwave-infrared (SWIR) and thermal imaging during dehydration with forced air have been promising for assessing lesion activity. Aim: We hypothesized that SWIR reflectance and thermal imaging methods can be used to monitor the activity of secondary caries lesions around composite restorations. The objective of this study was to employ these methods to measure the rate of fluid loss from lesions during dehydration with forced air to assess lesion activity. Approach: Sixty-three extracted human teeth with total of 109 suspected secondary lesions were examined using SWIR and thermal imaging during dehydration. The thickness of the highly mineralized transparent surface layer (TSL) at lesion interfaces indicative of lesion activity was measured by optical coherence tomography (OCT). Micro-computed tomography (MicroCT) was used to further confirm lesion severity and structure. OCT and MicroCT measurements of lesion structure, depth, and severity were correlated with fluid loss rates measured with SWIR reflectance and thermal imaging. Results: TSL thickness measured with OCT correlated with both SWIR reflectance and thermal measurements of rates of fluid loss ( p < 0.05 ). Increasing TSL thickness led to decreased permeability of lesions, potentially indicating full lesion arrest at TSL ≥ 70    μ m . SWIR performed better than thermal imaging for secondary lesion activity assessment, although both methods performed best on smooth surface lesions. Conclusions: Nondestructive SWIR reflectance and OCT imaging methods are promising for clinically monitoring the activity of secondary caries lesions.

Abstract Idiopathic Pulmonary Fibrosis (IPF) is a debilitating and fatal lung disease characterized by the excessive formation of scar tissue and decline of lung function. Despite extensive research, only two FDA-approved drugs exist for IPF, with limited efficacy and relevant side effects. Thus, there is an urgent need for new effective therapies, whose discovery strongly relies on IPF animal models. Despite some limitations, the Bleomycin (BLM)-induced lung fibrosis mouse model is widely used for antifibrotic drug discovery and for investigating disease pathogenesis. The initial acute inflammation triggered by BLM instillation and the spontaneous fibrosis resolution that occurs after 3 weeks are the major drawbacks of this system. In the present study, we applied micro-CT technology to a longer-lasting, triple BLM administration fibrosis mouse model to define the best time-window for Nintedanib (NINT) treatment. Two different treatment regimens were examined, with a daily NINT administration from day 7 to 28 (NINT 7–28), and from day 14 to 28 (NINT 14–28). For the first time, we automatically derived both morphological and functional readouts from longitudinal micro-CT. NINT 14–28 showed significant effects on morphological parameters after just 1 week of treatment, while no modulations of these biomarkers were observed during the preceding 7–14-days period, likely due to persistent inflammation. Micro-CT morphological data evaluated on day 28 were confirmed by lung histology and bronchoalveolar lavage fluid (BALF) cells; Once again, the NINT 7–21 regimen did not provide substantial benefits over the NINT 14–28. Interestingly, both NINT treatments failed to improve micro-CT-derived functional parameters. Altogether, our findings support the need for optimized protocols in preclinical studies to expedite the drug discovery process for antifibrotic agents. This study represents a significant advancement in pulmonary fibrosis animal modeling and antifibrotic treatment understanding, with the potential for improved translatability through the concurrent structural–functional analysis offered by longitudinal micro-CT.

Abstract Objectives To evaluate in the absence of teeth the variability of the mylohyoid line (ML), the microarchitecture of the adjacent bone, and whether the variable prominence/width of the ML is associated with the quality of the adjacent bone. Methods µCT scans of 28 human mandibles from anatomical specimens were analyzed. The following parameters were assessed in four edentulous areas (first and second premolar (PM), first, second, and third molar (M1/2/3)): ML width, cortical thickness (CtTh), average cortical- (Avg.Ct.BV/TV), and trabecular bone volume fraction (Avg.Tb.BV/TV). Results The ML width increased from the PM towards the M2 region, which also showed the highest variance (range: 0.4–10.2 mm). The CtTh showed a decrease in the M3 region, while Avg.Ct.BV/TV and Avg.Tb.BV/TV hardly differed among the regions. In the multivariable model on the effect of the various parameters on the ML width, only gender and tooth region were significant. Specifically, male specimens were associated with a wider ML width compared to female specimens and the M2 region was associated with a wider ML width compared to the other tooth regions. Conclusion The ML width was not associated with the cortical and trabecular bone quality in the adjacent bone, while gender and tooth region had a significant effect. Specifically, the ML width was lower in female, but peaked in the M2 region with a median width of 3–4 mm. Clinical relevance From a clinical point of view, it was confirmed that the ML is in general a highly variable structure, especially in the M2 region, but the ML width does not allow any conclusions on the bone quality. Altogether, this underlines the need for an individual and accurate diagnostic prior to any surgical intervention.

ObjectiveEvaluating the canal-centering and apical transportation ability of endodontic file systems working with different kinematics but of similar cross section. Materials and MethodsSixty human maxillary first molar mesiobuccal (MB) roots were assigned to three experimental groups based on instrumentation techniques: Reciproc Blue (RB), Mtwo (M2), and OneShape (OS). Pre- and post-instrumentation micro-computed tomographic analysis was performed. Centering ability and apical transportation were analyzed at 3 mm, 6 mm, and 9 mm short of the apex. Statistical analysis was conducted using Mann–Whitney U test and Kruskal–Wallis test. ResultsOS showed better canal-centering ability than RB and M2 at 3 mm, 6 mm, and 9 mm. No significant difference among the tested groups was observed during the assessment of apical transportation (P < 0.05). ConclusionThe systems evaluated safely prepared curved MB canals with minimal canal transportation. OS showed superior canal-centering ability compared to the other two groups.

Abstract Background Mammalian skeletons are largely formed before birth. Heterochronic changes in skeletal formation can be investigated by comparing the order of ossification for different elements of the skeleton. Due to the challenge of collecting prenatal specimens in viviparous taxa, opportunistically collected museum specimens provide the best material for studying prenatal skeletal development across many mammalian species. Previous studies have investigated ossification sequence in a range of mammalian species, but little is known about the pattern of bone formation in Carnivora. Carnivorans have diverse ecologies, diets, and biomechanical specializations and are well-suited for investigating questions in evolutionary biology. Currently, developmental data on carnivorans is largely limited to domesticated species. To expand available data on carnivoran skeletal development, we used micro-computed tomography (micro-CT) to non-invasively evaluate the degree of ossification in all prenatal carnivoran specimens housed in the Harvard Museum of Comparative Zoology. By coding the presence or absence of bones in each specimen, we constructed ossification sequences for each species. Parsimov-based genetic inference (PGi) was then used to identify heterochronic shifts between carnivoran lineages and reconstruct the ancestral ossification sequence of Carnivora. Results We used micro-CT to study prenatal ossification sequence in six carnivora species: Eumetopias jubatus (Steller sea lion, n = 6), Herpestes javanicus (small Indian mongoose, n = 1), Panthera leo (lion, n = 1), Urocyon cinereoargenteus (gray fox, n = 1), Ursus arctos arctos (Eurasian brown bear, n = 1), and Viverricula indica (small Indian civet, n = 5). Due to the relatively later stage of collection for the available specimens, few heterochronic shifts were identified. Ossification sequences of feliform species showed complete agreement with the domestic cat. In caniforms, the bear and fox ossification sequences largely matched the dog, but numerous heterochronic shifts were identified in the sea lion. Conclusions We use museum specimens to generate cranial and postcranial micro-CT data on six species split between the two major carnivoran clades: Caniformia and Feliformia. Our data suggest that the ossification sequence of domestic dogs and cats are likely good models for terrestrial caniforms and feliforms, respectively, but not pinnipeds.

The present study explores rare but taxonomically and geographically widespread cases of anterior body axial bifurcation in adult sea cucumbers (Echinodermata: Holothuroidea). One individual of Holothuria (Halodeima) grisea, a common intertidal species along the Atlantic coast of Brazil, was studied externally and internally. Individuals of Apostichopus californicus from the northeastern Pacific coast of Washington (USA), H. (Mertensiothuria) leucospilota in the Indian Ocean off La Réunion, H. (Panningothuria) forskali from the Atlantic coast of Spain, and Parastichopus tremulus from the northeastern Atlantic off Norway were also reported to display similar anterior body axial bifurcation. In each of these species, the anterior body presented two mouths with their respective crown of tentacles. In vivo observations of H. (Halodeima) grisea showed that the two tentacle crowns and mouths were independently functional. Micro‐computed tomography (μCT) revealed that the anterior region of the body (up to the pharynx) was duplicated. Internally, two aquapharyngeal bulbs were found, each with their own calcareous ring (one with two plates missing), madreporite, and Polian vesicles. The body presented a normal set of five longitudinal muscle bands, some of which bifurcated orally to support more than one calcareous ring plate. This is the first report of such abnormalities in Holothuroidea and hypotheses that may explain such phenomenon are discussed. [ABSTRACT FROM AUTHOR]

Objective Materials and Methods Results Conclusion To determine whether combining cross‐linked (CL) collagen‐integrated xenogeneic bone blocks stabilized with the fixation of resorbable collagen membranes (CM) can enhance guided bone regeneration (GBR) in the overaugmented calvarial defect model.Four circular defects with a diameter of 8 mm were prepared in the calvarium of 13 rabbits. Defects were randomly assigned to receive one of the following treatments: (i) non‐cross‐linked (NCL) porcine‐derived collagen‐embedded bone block covered by a CM without fixation (NCL + unfix group); (ii) NCL bone block covered by CM with fixation using bone‐tack (NCL + fix group); (iii) cross‐linked (CL) porcine‐derived collagen‐embedded bone block covered by CM without fixation (CL + unfix group); and (iv) CL bone block covered by CM with fixation using bone‐tack fixation (CL + fix group). The efficacy of GBR was assessed through histological and molecular analyses after 2 and 8 weeks.At 2 weeks, there were no significant differences in histologically measured areas of newly formed bone among the groups. At 8 weeks, however, the CL + fix group exhibited a larger area of new bone (5.08 ± 1.09 mm2, mean ± standard deviation) compared to the NCL + unfix (1.62 ± 0.42 mm2; p < .0083), NCL + fix (3.97 ± 1.39 mm2) and CL + unfix (2.55 ± 1.04 mm2) groups. Additionally, the expression levels of tumour necrosis factor‐alpha, fibroblast growth factor‐2, vascular endothelial growth factor, osteocalcin and calcitonin receptor were significantly higher in the CL + fix group compared to the other three groups (p < .0083).Cross‐linked bone blocks stabilized with collagen membrane fixation can significantly enhance GBR. [ABSTRACT FROM AUTHOR]

Electro-conductive fabrics are key materials for designing and developing wearable smart textiles. The properties of textile materials depend on the production method, the technique which leads to high conductivity, and the structure. The aim of the research work was to determine the factors affecting the electrical conductivity of woven fabrics and elucidate the mechanism of electric current conduction through this complex, aperiodic textile material. The chemical composition of the material surface was identified using scanning electron microscopy energy dispersion X-ray spectroscopy. The van der Pauw method was employed for multidirectional resistance measurements. The coefficient was determined for the assessment of the electrical anisotropy of woven fabrics. X-ray micro-computed tomography was used for 3D woven structure geometry analysis. The anisotropy coefficient enabled the classification of electro-conductive fabrics in terms of isotropic or anisotropic materials. It was found that the increase in weft density results in an increase in sample anisotropy. The rise in thread width can lead to smaller electrical in-plane anisotropy. The threads are unevenly distributed in woven fabric, and their widths are not constant, which is reflected in the anisotropy coefficient values depending on the electrode arrangement. The smaller the fabric area covered by four electrodes, the fewer factors leading to structure aperiodicity. [ABSTRACT FROM AUTHOR]

In the present study, anatomical assessment of zygomaticofacial foramina (ZFFs) and zygomatic canals communicating with ZFFs were performed using cadaver micro-computed tomography images. It was suggested that all ZFFs were located above the jugale (Ju)-zygomaxillare (Zm) line, which is the reference line connecting the Ju and Zm, and most were located in the zygomatic body area (ZBA). The anteroposterior position of the ZFF in the ZBA was within a middle to posterior region and was most often located slightly posteriorly in males and closer to the middle of the region in females. The mean distance from the Ju-Zm line to the ZFF in the ZBA was 12.36 mm (standard deviation [SD] 1.52 mm) in males and 11.48 mm (SD 1.61 mm) in females. In zygomatic canals communicating with ZFFs, most zygomatic canals were type I canals, communicating from the zygomaticoorbital foramen and harboring the zygomaticofacial nerve, and the others were type II canals, communicating from the zygomaticotemporal foramen and located near the posterior margin of the frontal process. These results provide useful anatomical information for preventing nerve injury during surgical procedures for zygomatic implant treatment. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the morphology of maxillary lateral incisors (MxLI) using micro-computed tomography (micro-CT). Materials and methods: The root canal configurations (RCC) of maxillary lateral incisors (MxLI) of a mixed Swiss-German population were examined using micro-CT, 3D imaging, and a 4-digit system code indicating the main root canal from coronal to apical thirds and the main foramina number. Results: The most frequently observed RCC of MxLI were 1-1-1/1 (Vertucci I/Ve I, 80.0%), 1-1-2/2 (Ve V, 7.3%), 1-2-1/1 (Ve III, 6.4%), 2-1-1/1 (Ve II, 1.8%), and 1-1-1/2 (1.8%)(n = 110). Three additional RCC were observed less frequently (0.9%). The MxLI showed one physiological foramen in 89.1%, two in 9.1%, and seldom three (1.8%). Most accessory canals were identified in the apical third of a root (20.0%), and no accessory canals in 72.7% of the samples. Conclusions: Detailed information on the internal morphology of MxLI of a Swiss-German population is given. The most frequently observed RCC of MxLI is 1-1-1/1 (Ve I). However, accessory canals may occur in all apical thirds, and 20% of all teeth investigated showed a challenging RCC for clinical treatment. Clinical relevance: This study offers clinicians comprehensive data on MxLI morphology, emphasizing the significance of understanding varied RCC and accessory canal presence for improving root canal treatment outcomes. Over 25% of teeth exhibited complex RCC or accessory canals, influencing decisions during root canal treatment. [ABSTRACT FROM AUTHOR]

Background and Objectives: In teeth with open apices, performing single session apexification is a challenging treatment due to the difficulty in handling mineral trioxide aggregate (MTA). Minimally invasive approaches in dentistry have also influenced the cavity designs in endodontics. Until now, different techniques have not been investigated in addition to manual condensation during the process of placing MTA in traditional (TradACs) or conservative (ConsACs) endodontic access cavities. The aim of this in vitro study was to compare and evaluate the obturation quality of MTA apical plugs placed with different techniques in TradACs or ConsACs. Materials and Methods: Sixty upper central teeth were divided into two main groups based on cavity design, and then each main group was further divided into three subgroups according to MTA placement techniques (n = 10): TradAC-manual, TradAC-manual + indirect ultrasonic activation, TradAC-manual + XP-endo Shaper (XPS), ConsAC-manual, ConsAC-manual + indirect ultrasonic activation, and ConsAC-manual + XPS. Subsequently, the porosity percentages in the MTA apical plug were analyzed using micro-computed tomography. The statistical analysis was performed using the Kruskal–Wallis H test and Mann–Whitney U test. Statistical significance was set at p < 0.05. Results: There were differences in volume of porosity percentages (%) according to cavity designs and MTA application techniques (p < 0.05). Except for the XPS group, more porosity was observed in ConsACs compared to TradACs. In TradACs, the significantly lowest open and total porosity was observed in the manual, ultrasonic, and XPS techniques, respectively. In ConsACs, the significantly lowest porosity was observed in the manual, XPS, and ultrasonic techniques, respectively (p < 0.05). Conclusions: In MTA obturation, cavity designs and application techniques had an impact on the MTA porosity. Creating an apical plug in ConsACs may result in more porosity compared to TradACs, especially when manual or indirect ultrasonic activation is preferred. Opting for the manual technique alone may be considered sufficient for controlling porosity for both TradACs and ConsACs. [ABSTRACT FROM AUTHOR]

Rhodoliths built by crustose coralline algae (CCA) are ecosystem engineers of global importance. In the Arctic photic zone, their three‐dimensional growth emulates the habitat complexity of coral reefs but with a far slower growth rate, growing at micrometers per year rather than millimeters. While climate change is known to exert various impacts on the CCA's calcite skeleton, including geochemical and structural alterations, field observations of net growth over decade‐long timescales are lacking. Here, we use a temporally explicit model to show that rising ocean temperatures over nearly 100 years were associated with reduced rhodolith growth at different depths in the Arctic. Over the past 90 years, the median growth rate was 85 μm year−1 but each °C increase in summer seawater temperature decreased growth by a mean of 8.9 μm (95% confidence intervals = 1.32–16.60 μm °C−1, p <.05). The decrease was expressed for rhodolith occurrences in 11 and 27 m water depth but not at 46 m, also having the shortest time series (1991–2015). Although increasing temperatures can spur plant growth, we suggest anthropogenic climate change has either exceeded the population thermal optimum for these CCA, or synergistic effects of warming, ocean acidification, and/or increasing turbidity impair rhodolith growth. Rhodoliths built by calcitic CCA are important habitat providers worldwide, so decreased growth would lead to yet another facet of anthropogenic habitat loss. [ABSTRACT FROM AUTHOR]

This study assessed the effect of intentional foraminal enlargement on the foramen and the apical root canal morphology. Sixty mesial roots of mandibular molars were scanned by micro-computed tomography. Their apical foramina were photographed with a stereomicroscope before and after preparation. Three groups were formed (n = 20) according to the working length (WL). G-1: foramen - 1 mm; G0: foramen; and G+1: foramen + 1 mm. Each group originated 2 subgroups (n = 10): G-1: Buchanan's patency (size 10 K-type file) and foraminal debridement (sizes 20, 25 and 30 K-type files); G0 and G+1: rotary foraminal enlargement (ProDesign S size 25/.08) or reciprocating foraminal enlargement (R25). The area, perimeter, transportation, and noninstrumented walls of the foramen were evaluated. The root canal transportation and the centering index of preparation at 1, 3 and 5 mm from the foramen were also assessed. Data were compared statistically (α = 5%). The instruments used at the foramen and 1 mm beyond promoted foraminal enlargement and transportation. Regarding NIW, there was no difference between mechanized foraminal enlargements performed at the foramen or 1 mm beyond, similar to the manual foraminal debridement group (P >.05). There was no difference in transportation and centralization at 1-, 3-, and 5-mm apical levels, regardless of the instrumentation systems. Mechanical preparation at the foramen, or 1 mm beyond, resulted in foraminal enlargement, transportation and were not able to touch all root canal walls that delimit the foramen. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effectiveness of the XP-endo Finisher R (XPFR; FKG Dentaire, La Chaux-de-Fonds, Switzerland) or the Flatsonic ultrasonic tip (Helse Ultrasonic, Santa Rosa de Viterbo, SP, Brazil) in removing remaining filling material after the retreatment of flattened root canals using micro–computed tomographic imaging. Twenty-four flattened distal root canals of mandibular molars with a buccolingual diameter 4 or more times larger than the mesiodistal diameter were prepared with Reciproc Blue (RB) R40 (VDW GmbH, Munich, Germany) and filled using the Tagger hybrid technique. All canals were retreated with RB R40, and apical enlargement was performed with RB R50 (VDW GmbH). The specimens were randomly distributed into 2 groups: XPFR or Flatsonic (n = 12). The percentage of remaining filling material after retreatment and centralization ability was evaluated. Data were submitted to Mann-Whitney, Wilcoxon, and unpaired t tests (α = 5%). Greater capacity to remove remaining filling material in the entire canal and the cervical and middle thirds was observed for the Flatsonic compared with the XPFR (P <.05). However, both supplementary cleaning techniques showed a similar percentage of residual filling material in the apical third (P >.05). No difference was observed in the centralization ability between the techniques (P >.05). The Flatsonic promotes greater removal of remaining filling material than the XPFR in the retreatment of flattened root canals. However, both supplementary cleaning approaches were similar in the apical third. The XPFR and Flatsonic were able to maintain root canal centralization. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate in the absence of teeth the variability of the mylohyoid line (ML), the microarchitecture of the adjacent bone, and whether the variable prominence/width of the ML is associated with the quality of the adjacent bone. Methods: µCT scans of 28 human mandibles from anatomical specimens were analyzed. The following parameters were assessed in four edentulous areas (first and second premolar (PM), first, second, and third molar (M1/2/3)): ML width, cortical thickness (CtTh), average cortical- (Avg.Ct.BV/TV), and trabecular bone volume fraction (Avg.Tb.BV/TV). Results: The ML width increased from the PM towards the M2 region, which also showed the highest variance (range: 0.4–10.2 mm). The CtTh showed a decrease in the M3 region, while Avg.Ct.BV/TV and Avg.Tb.BV/TV hardly differed among the regions. In the multivariable model on the effect of the various parameters on the ML width, only gender and tooth region were significant. Specifically, male specimens were associated with a wider ML width compared to female specimens and the M2 region was associated with a wider ML width compared to the other tooth regions. Conclusion: The ML width was not associated with the cortical and trabecular bone quality in the adjacent bone, while gender and tooth region had a significant effect. Specifically, the ML width was lower in female, but peaked in the M2 region with a median width of 3–4 mm. Clinical relevance: From a clinical point of view, it was confirmed that the ML is in general a highly variable structure, especially in the M2 region, but the ML width does not allow any conclusions on the bone quality. Altogether, this underlines the need for an individual and accurate diagnostic prior to any surgical intervention. [ABSTRACT FROM AUTHOR]

Background: Mammalian skeletons are largely formed before birth. Heterochronic changes in skeletal formation can be investigated by comparing the order of ossification for different elements of the skeleton. Due to the challenge of collecting prenatal specimens in viviparous taxa, opportunistically collected museum specimens provide the best material for studying prenatal skeletal development across many mammalian species. Previous studies have investigated ossification sequence in a range of mammalian species, but little is known about the pattern of bone formation in Carnivora. Carnivorans have diverse ecologies, diets, and biomechanical specializations and are well-suited for investigating questions in evolutionary biology. Currently, developmental data on carnivorans is largely limited to domesticated species. To expand available data on carnivoran skeletal development, we used micro-computed tomography (micro-CT) to non-invasively evaluate the degree of ossification in all prenatal carnivoran specimens housed in the Harvard Museum of Comparative Zoology. By coding the presence or absence of bones in each specimen, we constructed ossification sequences for each species. Parsimov-based genetic inference (PGi) was then used to identify heterochronic shifts between carnivoran lineages and reconstruct the ancestral ossification sequence of Carnivora. Results: We used micro-CT to study prenatal ossification sequence in six carnivora species: Eumetopias jubatus (Steller sea lion, n = 6), Herpestes javanicus (small Indian mongoose, n = 1), Panthera leo (lion, n = 1), Urocyon cinereoargenteus (gray fox, n = 1), Ursus arctos arctos (Eurasian brown bear, n = 1), and Viverricula indica (small Indian civet, n = 5). Due to the relatively later stage of collection for the available specimens, few heterochronic shifts were identified. Ossification sequences of feliform species showed complete agreement with the domestic cat. In caniforms, the bear and fox ossification sequences largely matched the dog, but numerous heterochronic shifts were identified in the sea lion. Conclusions: We use museum specimens to generate cranial and postcranial micro-CT data on six species split between the two major carnivoran clades: Caniformia and Feliformia. Our data suggest that the ossification sequence of domestic dogs and cats are likely good models for terrestrial caniforms and feliforms, respectively, but not pinnipeds. [ABSTRACT FROM AUTHOR]

Bone can adapt its microstructure to mechanical loads through mechanoregulation of the (re)modeling process. This process has been investigated in vivo using time-lapsed micro-computed tomography (micro-CT) and micro-finite element (FE) analysis using surface-based methods, which are highly influenced by surface curvature. Consequently, when trying to investigate mechanoregulation in tissue engineered bone constructs, their concave surfaces make the detection of mechanoregulation impossible when using surface-based methods. In this study, we aimed at developing and applying a volumetric method to non-invasively quantify mechanoregulation of bone formation in tissue engineered bone constructs using micro-CT images and FE analysis. We first investigated hydroxyapatite scaffolds seeded with human mesenchymal stem cells that were incubated over 8 weeks with one mechanically loaded and one control group. Higher mechanoregulation of bone formation was measured in loaded samples with an area under the curve for the receiver operating curve (AUC formation) of 0.633–0.637 compared to non-loaded controls (AUC formation : 0.592–0.604) during culture in osteogenic medium (p < 0.05). Furthermore, we applied the method to an in vivo mouse study investigating the effect of loading frequencies on bone adaptation. The volumetric method detected differences in mechanoregulation of bone formation between loading conditions (p < 0.05). Mechanoregulation in bone formation was more pronounced (AUC formation : 0.609–0.642) compared to the surface-based method (AUC formation : 0.565–0.569, p < 0.05). Our results show that mechanoregulation of formation in bone tissue engineered constructs takes place and its extent can be quantified with a volumetric mechanoregulation method using time-lapsed micro-CT and FE analysis. Many efforts have been directed towards optimizing bone scaffolds for tissue growth. However, the impact of the scaffolds mechanical environment on bone growth is still poorly understood, requiring accurate assessment of its mechanoregulation. Existing surface-based methods were unable to detect mechanoregulation in tissue engineered constructs, due to predominantly concave surfaces in scaffolds. We present a volumetric approach to enable the precise and non-invasive quantification and analysis of mechanoregulation in bone tissue engineered constructs by leveraging time-lapsed micro-CT imaging, image registration, and finite element analysis. The implications of this research extend to diverse experimental setups, encompassing culture conditions, and material optimization, and investigations into bone diseases, enabling a significant stride towards comprehensive advancements in bone tissue engineering and regenerative medicine. [Display omitted] [ABSTRACT FROM AUTHOR]

In a recent stereotactic body radiation therapy animal model, radiation pneumonitis and radiation pulmonary fibrosis were observed at around 2 and 6 weeks, respectively. However, the molecular signature of this model remains unclear. This study aimed to examine the molecular characteristics at these two stages using RNA-seq analysis. Transcriptomic profiling revealed distinct transcriptional patterns for each stage. Inflammatory response and immune cell activation were involved in both stages. Cell cycle processes and response to type II interferons were observed during the inflammation stage. Extracellular matrix organization and immunoglobulin production were noted during the fibrosis stage. To investigate the impact of a 10 Gy difference on fibrosis progression, doses of 45, 55, and 65 Gy were tested. A dose of 65 Gy was selected and compared with 75 Gy. The 65 Gy dose induced inflammation and fibrosis as well as the 75 Gy dose, but with reduced lung damage, fewer inflammatory cells, and decreased collagen deposition, particularly during the inflammation stage. Transcriptomic analysis revealed significant overlap, but differences were observed and clarified in Gene Ontology and KEGG pathway analysis, potentially influenced by changes in interferon-gamma-mediated lipid metabolism. This suggests the suitability of 65 Gy for future preclinical basic and pharmaceutical research connected with radiation-induced lung injury. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Polymerization reactions in a new generation bulk-fill composites carried out in a short time with high irradiation, raise concerns about curing processes. With micro-computed tomographic evaluation, it is possible to investigate polymerization shrinkage, and subsequent gap and void formation in dental materials. OBJECTIVES: The aim of this study was to evaluate the void formation in bulk-fill composites light-cured with different modes using micro-computed tomography. MATERIAL AND METHODS: Class I preparations were made in 25 molars that were randomly divided into subgroups, according to resin composite and curing mode used: Tetric EvoCeram (TEC)*high power mode, TEC*turbo mode, Tetric PowerFill (TPF)*high power mode, TPF*turbo mode, and TPF*3s mode. Each tooth was scanned at two time intervals: pre- and post-cure. RESULTS: After light-curing, a significant increase in the total volume of internal void was noted for both composites cured with high power mode compared with pre-cure. The difference between the sub-groups at post-cure was also significant. While TEC exhibited similar values in terms of different curing modes, turbo and 3s modes caused a significant difference in TPF group, and the lowest void percentage was detected in 3s mode. CONCLUSIONS: Internal void formation results from an interplay of different factors, including composition of materials and curing modes. [ABSTRACT FROM AUTHOR]

A cemental tear (CeT) is a definitive clinical entity and its radiographic appearance is well known in single‐rooted teeth. However, the imaging features of CeT in multi‐rooted teeth have not been clarified. We report a case of CeT which arose in the maxillary first molar and exhibited an unusual appearance in cone‐beam computed tomography images. The torn structure was verified as cementum by micro‐computed tomography and histological analysis. The hypercementosis, most likely induced by occlusal force, might have been torn from the root by a stronger occlusal force caused by the mandibular implant. An unusual bridging structure was created between the two buccal roots. These features may occur in multi‐rooted teeth with long‐standing deep pockets and abscesses that are resistant to treatment. [ABSTRACT FROM AUTHOR]

Porous materials, such as carbonate rocks, frequently have pore sizes which span many orders of magnitude. This is a challenge for models that rely on an image of the pore space, since much of the pore space may be unresolved. In this work, sub‐resolution porosity in X‐ray images is characterized using differential imaging which quantifies the difference between a dry scan and 30 wt% potassium iodide brine saturated images. Once characterized, we develop a robust workflow to incorporate the sub‐resolution pore space into a network model using Darcy‐type elements called microlinks. Each grain voxel with sub‐resolution porosity is assigned to the two nearest resolved pores using an automatic dilation algorithm. By including these microlinks with empirical models in flow modeling, we simulate single‐phase and multiphase flow. By fine‐tuning the microlink empirical models, we match permeability, formation factor (the ratio of the resistivity of a rock filled with brine to the resistivity of that brine), and drainage capillary pressure to experimental results. We then show that our model can successfully predict steady‐state relative permeability measurements on a water‐wet Estaillades carbonate sample within the uncertainty of the experiments and modeling. Our approach of incorporating sub‐resolution porosity in two‐phase flow modeling using image‐based multiscale pore network techniques can capture complex pore structures and accurately predict flow behavior in porous materials with a wide range of pore size. Key Points: A dilation‐based algorithm adds sub‐resolution porosity, quantified by differential imaging, as microlinks to an extracted pore networkEmpirical models are used to characterize the flow properties of microlinksThe tuned multiscale network, using permeability, formation factor, and capillary pressure, matches experimental relative permeability [ABSTRACT FROM AUTHOR]

Fabric characteristics and shear deformation behaviour were analysed in four intact small-scale samples, including two disturbed and two undisturbed samples of naturally deposited sand from a shoal in the San Francisco Bay. Triaxial compression tests were performed on each sample while incrementally imaging with X-ray micro-computed tomography (XRCT). The grains in each intact sample exhibited a nearly unidirectional orientation with their long axes oriented within a narrow range of horizontal directions, in stark contrast to the randomly oriented grains of a reconstituted sample. The disturbed intact samples exhibited lower peak strengths and lower yet positive rates of dilation as compared with undisturbed samples. Higher rates of dilation corresponded with larger quantifiable decreases in the average number of grain-to-grain contacts and contact areas per grain within the shear band. The XRCT images of the shear bands were quantified by way of large incremental deviatoric strains and large incremental grain rotations. The grain orientations within the fully developed shear band of each sample reached a consistent orientation independent of their initial fabric. These results are a promising step toward a systematic study of granular deposits from different depositional environments needed for the development of more advanced models of their mechanical behaviour. [ABSTRACT FROM AUTHOR]

Premise of research. The genus Carya is a classic example of the eastern North American–eastern Asian disjunct distribution, but its biogeographic history is not well understood because many species present in the Cenozoic of Europe have ambiguous relationships to extant species. Methodogy. The morphology and anatomy of fossil nuts of C. ventricosa (Sternberg ex Brongniart) Unger from the Miocene of Salzhausen, Germany, of eight extant Carya species, and of four extant Juglans species were investigated using micro–computed tomography scanning. Carpological characteristics were analyzed using VG Studio for comparison. The morphological characters of 25 other Carya fruit fossils known from the literature were studied for comparison. Pivotal results. The peripheral course of the placental bundles within the primary septum of C. ventricosa confirms its identity to the genus Carya and distinguishes it from Juglans and from other genera of the Juglandaceae. Detailed comparison of carpological morphology and anatomy indicates that C. ventricosa is readily distinguished from extant North American species and more closely resembles the East Asian tropical C. poilanei ; both have a prominent low-density layer and/or prominent lacunae in the nutshell and contrast with other species in lacking a sharply defined pair of internal longitudinal ribs. The well-developed secondary septum in C. poilanei differs from the weakly developed, nearly absent secondary septum in C. ventricosa. The cuneate base of the locule distinguishes C. ventricosa from all extant species. Conclusions. Carya poilanei is the closest extant species to C. ventricosa. Europe might have been a key center of Cenozoic diversification and served as the ancestral area of the extant East Asian Carya lineages. [ABSTRACT FROM AUTHOR]

Increasing the amount of crushed natural and recycled fine aggregates in mortar and concrete can help to reduce depletion of resources and increase the recycling rate of construction and demolition waste. Differences in particle morphology influence fresh and hardened mortar and concrete properties. The quantitative assignment of this impact to specific characteristics, such as shape or angularity in differentiation to other mix design parameters, is currently scarcely known. Therefore, a multiple linear regression analysis was performed to investigate the impact of crushed natural and recycled fine particles on rheological and strength properties of mortar. The emphasis lies on the impact of differences in shape and angularity, which were quantified by the three-dimensional particle representation obtained from micro-computed tomography. A total of 160 mortar mixtures containing 5 sands of different origins and varying water-to-cement ratios, binder-to-aggregate ratios, and shapes of grading curves were produced. The results indicate that the particle shape and angularity of the crushed natural and recycled fine aggregates had a complex impact on fresh and hardened mortar properties and interacted with other mix design parameters. Careful composition of the aggregate fraction with respect to shape and angularity and their interaction with mix design parameters is necessary to maintain sufficient mortar properties. [ABSTRACT FROM AUTHOR]