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Objectives: Primary hyperparathyroidism (PHPT) is a disorder marked by chronic parathyroid hormone hypersecretion, which affects bone turnover and remodelling processes. With a loss of bone density and an increase in bone porosity, the cortical compartment is most severely impacted. The study's goal is to assess PHPT's effects on the volumetric bone mineral density (vBMD) of the femur's trabecular compartment as well as the vBMD and thickness of the cortical bone. Methods: This is a retrospective case–control study, valuating age, biochemical doses, anthropometric measurements, and bone measurements. Between 2011 and 2016, 74 Caucasian Italian women and men with PHPT were sought out. Biochemical analyses were added to bone mineral density (BMD) values found in the lumbar spine and femoral neck. Proximal femur parameters such as cortical and trabecular volumetric (v) BMD, cortical thickness (CTh) and surface (s) BMD were analyzed by 3D-DXA software (3D-SHAPER Medical, Spain). Results: The findings showed a negative correlation between PHPT patients and controls, which was equally affecting the cortical and trabecular compartments. This correlation was especially evident in the areal BMD (aBMD) and vBMD measurements. Nonetheless, no appreciable correlation was found between the cortical level and the thickness of the cortical bone. Conclusions: Parathormone (PHT) levels had an adverse effect on the cortical, trabecular volumetric density in this investigation, as was expected. Cortical thickness, however, is unaffected significantly. The literature and these findings are consistent. [ABSTRACT FROM AUTHOR]

During their development, some species of salmonids may occasionally experience skeletal deformations. Several methodologies are currently being used for the diagnosis of such malformations, among which X-rays, histological techniques, diaphanization coupled either with Alizarin Red or Alcian Blue stains, as well as Scanning Electron Microscopy (SEM) can be mentioned. Each one of those methods presents inherent advantages and disadvantages. The purpose of this study was twofold: Firstly, to evaluate and compare the effectiveness of microcomputed tomography (Micro-CT) technology for anatomical analysis, three-dimensionally reconstructing the obtained images; and secondly, to contrast those images with the results obtained through the diaphanization technique. The caudal fins of five specimens of the Oncorhynchus kisutch salmon were analyzed: Two specimens were subjected to diaphanization and three were processed for Micro-CT analysis, using the BRUKER SkyScan 1272 equipment. The Micro-CT technology demonstrated superiority in the resolution of bone structures, facilitating a detailed exploration of morphological variations, as well as the distribution of mineral density. This experimental approach allowed us to identify anomalies in the morphology and growth of the last vertebrae and dorsal lepidotrichiae, as well as an increased mineral density in the malformed dorsal lepidotrichiae. The higher resolution provided by Micro-CT not only enhances our understanding of the fish ontogeny and its adaptation to diverse environments, but also opens innovative perspectives for the study of the evolution of locomotor strategies and adaptive responses to environmental changes. [ABSTRACT FROM AUTHOR]

ObjectivesThe lack of standardized X-ray imaging remains a challenge for comparative studies on spatial scans acquired from different clinic-specific X-ray scanners. The central objectives of this study are: 1) to delineate mineral density (MD) values, and 2) generate spatial MD maps of various physiologic and pathologic biominerals, and 3) propose a standardization protocol within the safe-operating zone of a CT scanner that underpins normalization of absorbed dose to shape and density of tissues.MethodsA systematic approach to propose a standardization protocol for CT imaging in vivo included: 1) estimation of pathologic MD ranges by performing a comparative meta-analysis on 2009-2019 data from the PubMed database; 2) calibration of cone-beam CT (CBCT) and micro-CT scanners with phantoms of known mineral densities (0, 250, 500, 750 and 3000 mg/cc) and shapes (cylinders and polyhedrons); 3) scanning craniofacial bones (N = 5) and dental tissues (N = 5), and ectopic minerals from humans (N = 3 each, pulp, salivary gland, kidney and prostrate stones, and penile and vascular plaques); 4) underscoring the effect of shape-factor (surface area-to-volume ratio) on MD of biominerals.ResultsHigher MDs of physiologic and pathologic cortical bones (504-1009 mg/cc) compared to trabecular bone (82-212 mg/cc) were observed. An increase in shape-factor increased the CBCT error in MD measurement and revealed that the scanner resolution is dependent on the absorbed dose and shape-factor of detectable features.SignificanceCT scanners should be calibrated with phantoms containing segments of known shape-factors and mineral densities to identify safe-operating zones. The calibrated approach will narrow the gap between length-scale dependent measurements, and will permit spatiotemporal quantitative and reliable detection of pathologies.

The article discusses the use of race and ethnicity in fracture risk assessment, highlighting disparities in osteoporosis screening and treatment in the US. It questions the validity of race and ethnicity adjustments in fracture risk prediction models like US-FRAX, suggesting a need for more inclusive and population-based approaches. The ASBMR Task Force recommends removing race and ethnicity adjustments from fracture risk prediction models and emphasizes the importance of diverse data collection to improve fracture risk prediction for all individuals, especially those historically underrepresented in skeletal research. [Extracted from the article]

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department 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.)

Abstract Backgrounds We aimed to explore the relationship between diabetes status and bone mineral density (BMD) among adults with pre-diabetes and diabetes. Methods We collected and analyzed five cycles (2005–2006, 2007–2008, 2009–2010, 2013–2014, and 2017–2018) data from NHANES. We removed the individuals containing missing values. The linear regression models were used to explore the relationship between diabetes status and bone mineral density. Finally, we performed subgroup analyzes by age, sex and race to find special populations. Result Finally, 9661 participants with complete data were involved in the study. 944 were diagnosed with pre-diabetes, and 2043 were with diabetes. We found that bone mineral density in the hip, femoral neck, and lumbar spine showed an upward trend in both prediabetic and diabetic patients in the three linear regression models. Further, after subgroup analysis, we found that this trend was more prominent in whites race, women, and those over 50 years old. Conclusion Using NHANES data from 2005 to 2018, we found that patients with abnormal glucose metabolism had increased bone mineral density.

This study aimed to compare the mean mineral density difference (mMDD) and surface morphology of 10- and 60-s silver diamine fluoride (SDF)-applied dentin carious lesions and to study the effect of an additional 20-s light curing (LC) on SDF-treated teeth. Forty primary molar blocks with natural dentin carious lesions were measured for baseline lesion depth and mineral density using Image-Pro Plus software. The samples were randomly distributed into 4 groups; 38% SDF applied for 1) 10-s (10SDF), 2) 60-s (60SDF), 3) 10-s + LC (10SDF + LC), 4) 60-s + LC (60SDF + LC) and an additional control group to assess the outcome of pH-cycling only. Then all the groups underwent a 7-d bacterial pH-cycling. The dentin carious lesions' mMDD was determined by digital subtraction radiographic analysis. The surface morphology and elemental profile were assessed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The mMDD of the dentin lesions was analyzed using two-way ANOVA, generalized linear models analysis. Light curing was the only factor that affected the mMDD (p = 0.007). The mMDD in the 10SDF + LC and 60SDF + LC groups were significantly higher than those without light curing (p = 0.041 and 0.041, respectively). The 60SDF + LC group demonstrated a significantly higher mMDD than the 10SDF group (p = 0.010), while that in the 10SDF + LC group was similar to the 60SDF group (p = 1.00). Scanning electron microscopy revealed denser mineral content layers, which were likely silver and chloride, in the 10SDF + LC and 60SDF + LC groups than in the 10SDF and 60SDF groups, respectively. In conclusion, shortened application time with light curing enhanced SDF remineralization similarly to the conventional method. [ABSTRACT FROM AUTHOR]

Simple Summary: The tooth is composed of three mineralized tissues: enamel, dentin, and cementum. Micro-computed tomography (mCT) is an imaging technology based on X-rays that allows non-invasive morphological and quantitative analysis. The present work aimed to determine the relative mineral density (MD) of the feline tooth using mCT. The studied sample consisted of nine canines extracted from European Shorthair cats due to medical indication. These teeth were evaluated through dental radiography and, using mCT, the values of MD of the root of each tooth and of specific segments corresponding to the coronal, middle, and apical thirds of the root were determined. Mean MD of root tissues was 1.374 ± 0040 g·cm−3, and of hard root tissues 1.402 ± 0.035 g·cm−3. The study of MD could become an ancillary method for the diagnosis and characterization of dental pathology. The tooth is made up of three mineralized tissues, enamel, dentin, and cementum, which surround a non-mineralized tissue called the dental pulp. Micro-computed tomography (mCT) is an imaging technology based on X-rays that allows non-invasive visualization of objects at a microscopic scale, according to their radiopacity and in three dimensions (3D). Likewise, it allows the subsequent execution of morphological and quantitative analysis of the objects, such as, for example, the determination of the relative mineral density (MD). The present work aimed to describe the MD of feline teeth using mCT. The studied sample consisted of four European Shorthair cats, from which nine canine teeth were extracted per medical indication. These teeth were evaluated through dental radiography before and after their extraction. Using mCT and the CTAn software, the values of the relative mineral density of the root of each tooth and of specific segments corresponding to the coronal, middle, and apical thirds of the root were determined. Mean MD of root tissues was 1.374 ± 0040 g·cm−3, and of hard root, tissues was 1.402 ± 0.035 g·cm−3. Through mCT, it was possible to determine the mean MD values of feline canine teeth. The study of MD could become an ancillary method for the diagnosis and characterization of dental pathology. [ABSTRACT FROM AUTHOR]

Backgrounds: We aimed to explore the relationship between diabetes status and bone mineral density (BMD) among adults with pre-diabetes and diabetes. Methods: We collected and analyzed five cycles (2005–2006, 2007–2008, 2009–2010, 2013–2014, and 2017–2018) data from NHANES. We removed the individuals containing missing values. The linear regression models were used to explore the relationship between diabetes status and bone mineral density. Finally, we performed subgroup analyzes by age, sex and race to find special populations. Result: Finally, 9661 participants with complete data were involved in the study. 944 were diagnosed with pre-diabetes, and 2043 were with diabetes. We found that bone mineral density in the hip, femoral neck, and lumbar spine showed an upward trend in both prediabetic and diabetic patients in the three linear regression models. Further, after subgroup analysis, we found that this trend was more prominent in whites race, women, and those over 50 years old. Conclusion: Using NHANES data from 2005 to 2018, we found that patients with abnormal glucose metabolism had increased bone mineral density. [ABSTRACT FROM AUTHOR]

The development of new modalities for kidney stone prevention rests upon understanding the progression of mineralization within the renal pyramid. The progression from small foci of mineralized volumes within the renal pyramid to larger interstitial plaques that ultimately lead into clinically detectable calcium-based stones on calcium phosphate stems will be presented through correlative microscopy approach. High resolution X-ray computed tomography (micro-XCT), electron microscopy, and energy dispersive X-ray (EDX) compositional analyses of interstitial plaques, stems, and attached stones were performed. Increase in mineral density progressed with mineralization severity, with the highest mineral densities detected within mature Randall's plaque and stems to which kidney stones were attached. EDX analyses revealed variable elemental composition within interstitial plaque, stems, and stones. Micro-XCT reconstructions of stones with stems enabled visualization of unoccluded tubules within stems, with average tubule diameters corresponding to thin limbs of Henle, blood vessels, and collecting ducts. Correlative microscopy confirmed that the progression of mineralization leading to calcium-based nephrolithiasis occurs through a continuum involving four anatomically and structurally distinct biomineralization regions: 1) proximal intratubular mineralization within the renal pyramid; 2) interstitial Randall's plaque near the tip of the papilla; 3) emerging plaque (stems); and, 4) the body of heterogeneous stones.Statement of significanceNephrolithiasis is a common condition affecting nearly 1 in 11 Americans. The most common type of stone, calcium oxalate is known to form on a calcium phosphate deposit on the renal papilla known as Randall's plaque. Novel imaging techniques have identified distinct regions of biomineralization not just at the tip, but throughout the renal papilla. The classic understanding of Randall's plaque formation is reformulated using correlative imaging techniques. This study establishes a stepwise progression of anatomically-specific biomineralization events including, 1) proximal intratubular mineralization within the renal pyramid; 2) interstitial Randall's plaque near the tip of the papilla; 3) emerging plaque (stems); and, 4) the body of heterogeneous stones, and provides insights into the need for plausible site-specific therapeutic intervention.

Objectives: Comparison of maxillary, mandibular, dental crown and root mineral density in human skeletons identified in historical excavations with today's human maxillary, mandibular dental crown and root., Methods: After the skull images were obtained, four groups were created: maxilla 1, mandible 1 from the old period, maxilla 2 from the images taken from today's patients, and mandible 2 from the images taken from today's patients. Seventeen skeletons were previously classified as young age, middle age, and older age. Among the archive tomography images, 17 images from young (15-35), middle (36-56) and older (57 and over) age images were included in the study. HU value of the desired region was calculated automatically by the device using Region of interest (ROI)., Results: In this study, 34 jaws and 68 teeth were evaluated, including 7 mandibles and 10 maxillae from the late Roman period, and 8 mandibles and 9 maxillae from today's people. The average HU value of the crowns of mandibular anterior teeth from the late Roman period was measured as 2406.0. The average HU value of the crowns of maxillary anterior teeth was found to be 3383.8. In the posterior aspect, the average crown HU value measured in the maxilla was found to be higher than that in the mandible., Conclusions: The finding showed that the density of dental tissues of ancient people, such as enamel and dentin forming the crown, and cementum and dentin forming the root, was significantly higher than today's people., Competing Interests: Conflict of interests The authors declare that they have no conflict of interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

This article aimed to achieve a better understanding of cementum hyperplasia in the maxillary second molars lost due to periodontitis. Six maxillary second molars with hypercementosis were measured for the mineral concentration using micro-computed tomography and calcium element distributions using electron microprobe analysis. Calcium was distributed throughout the cementum, although the mineral concentration differed based on the cementum depth. The hyperplastic cementum was of the extrinsic fiber-rich cellular mixed stratified type. These results have implications for future studies aiming to diagnose hypercementosis. Further studies are needed to investigate the composition of the cementum matrix. • Etiology of hypercementosis is unknown. • Multiple methods of investigation were used to understand cementum hyperplasia. • Micro-CT, EPMA, and histological observation were applied to hypercementosed molars lost due to periodontitis. • No difference in the Ca distribution between the superficial and deep parts of hyperplastic cementum was observed. • High and low mineral concentrations were confirmed at hyperplastic cementum in the molars lost due to periodontitis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the change in demineralisation depth (DD)and mineral density (MD) over time in primary teeth exposed to a demineralisation protocol with microcomputed tomography (microCT). Methods: Caries lesions were artificially induced on the labial surfaces of 9 primary incisors by way of a demineralisation protocol using 0.1 M lactic acid with 10% methylcellulose gel for 7 and 14 days. The specimens were scanned with microCT and CTAn software (Bruker, Billerica, MA, USA) was used to analyse the changes in DD and MD. Statistical analyses were performed using SPSS software (IBM, Armonk, NY, USA). Repeated analysis of variance (ANOVA) test and Pearson bivariate correlation were used and the level of significance was set at P < 0.05. Results: The DD ranged from 0.00 to 0.99 µm (mean ± standard deviation [SD] 0.70 ± 0.43 µm) at baseline, 11.18 to 29.5 µm (18.15 ± 5.23 µm) at 7 days and 18.00 to 55.30 µm (34.20 ± 8.70 µm) at 14 days. The MD for all specimens (n = 9) ranged from 1.48 to 1.76 g/cm³ (1.65 ± 0.08 g/cm³) at baseline, from 1.47 to 1.74 g/cm³ (1.62 ± 0.08 g/cm³) at 7 days demineralisation and 1.33 to 1.72 g/cm³ (1.54 ± 0.13 g/cm3) at 14 days. There were statistically significant differences in DD (P < 0.001) and MD (P = 0.016) between different durations of demineralisation. Conclusion: DD and MD change with time after being exposed to demineralising solution. MicroCT is a nondestructive method that allows repeated MD evaluations of the same sample. [ABSTRACT FROM AUTHOR]

Objectives: Autosomal‐dominant hypocalcified amelogenesis imperfecta (ADHCAI) shows phenotypic heterogeneity. Our aim was to characterise the ADHCAI phenotypes, tooth properties and genotypes. Methods: Three unrelated ADHCAI probands and seven additional affected members of the three families were recruited. Mutations were identified by exome and Sanger sequencing, and haplotypes by SNP array. Tooth colour, roughness, density, nanohardness, minerals and ultrastructure were investigated. Results: Ten participants were heterozygous for the FAM83H mutation c.1387C>T (p.Gln463*). All shared a 3.43 Mbp region on chromosome 8q24.3 encompassing the FAM83H variant, indicating a common ancestry. The c.1387C>T was estimated to be 23.8 generations or 600 years. The FAM83H enamel had higher roughness and lower lightness, density, nanohardness, and calcium and phosphorus levels than controls. Blunted enamel rods, wide interrod spaces and disorganised dentinoenamel junctions were observed. Evaluating the patients with the same mutation and reviewing others with different mutations in FAM83H revealed that the FAM83H heterogeneous phenotypes are age‐influenced. Tooth colour and surface texture change with ageing. Conclusions: FAM83H enamel demonstrated decreased lightness, density, hardness, calcium, phosphorus and defective ultrastructure. We have identified that the phenotypic variation in FAM83H‐associated ADHCAI is age‐related. Awareness of the correlation between age and clinical features of FAM83H‐ADHCAI can help dentists make an accurate diagnosis. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize natal and neonatal teeth using micro-computed tomography. A total of 4 natal and 11 neonatal teeth were used for the analysis. The reconstructed scans were assessed for the maximum enamel/dentin thickness and mineral density (MD). The scanned specimens were 3D reconstructed to qualitatively determine the surface topography. The dentin thickness was two-fold greater than enamel thickness for both natal and neonatal teeth (p < 0.05). The cervical third enamel MD remained undetermined in natal and neonatal teeth. The dentin MD at the cervical third for neonatal teeth was significantly lower than the incisal and middle third dentin (p < 0.05). Similarly, the dentin MD at the cervical third of neonatal teeth was significantly lower than the cervical third dentin MD of natal teeth (p < 0.05). Our qualitative analysis suggests that the cervical thirds of both natal and neonatal teeth are peculiar of an anomalous structure, with neonatal teeth showing an irregular outline. Under the conditions of the present study, it can be concluded that the neonatal teeth studied exhibited a distinguishable aberrant structure compared to the natal teeth. Therefore, the natal teeth unfold as a more organized, three-dimensional structure compared to the neonatal teeth. [ABSTRACT FROM AUTHOR]

The purpose of the present cohort study was a quantitative assessment of the enamel, dentin, and alveolar bone mineral density (BMD) using Cone Beam Computed Tomography (CBCT) scans in patients with X-linked hypophosphatemic rickets (HLHR) and hypophosphatasia (HPP) and a comparison with the data obtained from the control group. Methods and Results: The unrepresentative, non-random sample included 30 CBCT scans of children with genetically and biochemically confirmed XLHR (OMIM #307800) and HPP (OMIM: 146300, 241510, 241500, and 146300). X-ray examination and dental care were carried out in the Radiology Diagnostics Department and Pediatric Dentistry Department at Moscow State University of Medicine and Dentistry named after AI Evdokimov. The mineral density of calcified tissues (enamel, dentin, and alveolar bone) was evaluated using i-CAT Vision TM software options on reconstructed CBCT axial views. The images of all XLHR and HPP patients visualized large pulp chambers with prominent pulp horns extending to the dentin-enamel junction. The present study revealed poor alveolar bone mineralization in patients with HPP and XLHR. Analysis of CBCT scans showed a significant dentine hypodensity in XLHR patients, which may contribute to the emergence of multiple, spontaneous, periapical abscesses spreading rapidly in the jawbone. Conclusion: Data obtained could be used for planning dental treatment of patients with XLHR and HPP.

Abstract Background This study aimed to compare the efficacies of experimental toothpastes containing functionalized tricalcium phosphate (fTCP) with and without fluoride for in vitro enamel remineralization under pH-cycling conditions. Methods To create artificial white spot lesions, 36 bovine enamel specimens were immersed in a demineralization solution for 10 days. During pH-cycling for 12 days, the specimens were divided into four groups based on the experimental toothpaste type used: (a) fTCP-free, fluoride-free (fTCP − F −); (b) fTCP-containing, fluoride-free (fTCP + F −); (c) fTCP-free, fluoride-containing (fTCP − F +); and (d) fTCP-containing, fluoride-containing (fTCP + F +). Micro-focus X-ray computed tomography (μCT) scans of all specimens were obtained before demineralization, after demineralization, and after pH-cycling. The mineral density and mineral loss (ΔZ) in the enamel subsurface lesions were measured and the percentage of remineralization (%R) was calculated from ΔZ after demineralization and pH-cycling. One-way ANOVA with Tukey’s test was used for statistical analysis of the %R values. The treated enamel surface was investigated via scanning electron microscopy (SEM). Results The fTCP − F − group presented with the lowest amount of mineral gain after pH-cycling. In contrast, the fTCP + F + group showed the highest degree of remineralization within all lesion parts. The %R was highest in the fTCP + F + group (38.2 ± 7.8, all P

Paddy-wheat crop rotation is responsible for declining soil health, underground water table, arising new micronutrient deficiencies, new weed flora, and resistance to herbicides, declining both land and water productivity and is claimed to be capital and energy-intensive, more particularly in emerging countries. This is further aggravated when micronutrients are deficient, particularly zinc (Zn), which plays an important role in human health, especially in developing countries. Zn biofortification is a technique in which the inherent Zn status of the edible portion of plants is improved by simply spraying a Zn solution onto the crop or through a soil application at a predetermined stage and a proper dose. The concentration of Zn within a wheat grain is genotype-dependent and interacts with the environment, inducing variation in a grain’s concentration of micronutrients. Grain quality parameters are positively correlated with a higher dose of nitrogen in the late reproductive stage. Broadcasting of ZnSO4·7H2O at 62.5 kg ha−1 and foliar application of Zn chelates such as Zn–HEDP (C) at 2 g L−1, Zn–HEDP (L) at 3 g L−1, or a 0.4–0.5% ZnSO4 solution during grain development stage enhanced the growth, productivity, and micronutrients concentration in the edible portion of the plant which further improves the quality of wheat grains and ultimately improves human health in the region. Given the central importance to Zn in cereal-based nutrition, zinc biofortification appears as an innovative technology to alleviate the zinc deficiency in human health, especially on the Indian subcontinent, by applying Zn either as a foliar or soil application.

Background: As bone mineral is one of the major determinants of bone strength, its exact measurement should be useful for the diagnosis of osteoporosis, as well as for the prediction of fracture risk and monitoring of therapeutically response. Aims: The aim of this study was to investigate computer-assisted measurement of radiographical alveolar bone density using intraoral radiographs, especially comparison between men and women in young adults. Materials and Methods: Forty-two patients in young adults (20 men and 22 women; age 22–25 years; and mean age 23.2 years) of the mandibular premolar region who underwent intraoral radiographs with imaging plate (IP) detector and computer analysis system “DentalSCOPE” were included in this study. The DentalSCOPE had a special X-ray beam indicator in which a special calcium carbonate reference object was embedded. IP-based digital X-ray images were input into the DentalSCOPE system. The DentalSCOPE software measured the image density of the reference object automatically and calculated the mineral density value of an arbitrary region of interest (ROI). The mineral density of a rectangular ROI in the periapical region of mandibular premolars was evaluated. The age and alveolar bone density were compared between men and women using the Mann–Whitney U-test. P

The tooth is made up of three mineralized tissues, enamel, dentin, and cementum, which surround a non-mineralized tissue called the dental pulp. Micro-computed tomography (mCT) is an imaging technology based on X-rays that allows non-invasive visualization of objects at a microscopic scale, according to their radiopacity and in three dimensions (3D). Likewise, it allows the subsequent execution of morphological and quantitative analysis of the objects, such as, for example, the determination of the relative mineral density (MD). The present work aimed to describe the MD of feline teeth using mCT. The studied sample consisted of four European Shorthair cats, from which nine canine teeth were extracted per medical indication. These teeth were evaluated through dental radiography before and after their extraction. Using mCT and the CTAn software, the values of the relative mineral density of the root of each tooth and of specific segments corresponding to the coronal, middle, and apical thirds of the root were determined. Mean MD of root tissues was 1.374 ± 0040 g·cm−3, and of hard root, tissues was 1.402 ± 0.035 g·cm−3. Through mCT, it was possible to determine the mean MD values of feline canine teeth. The study of MD could become an ancillary method for the diagnosis and characterization of dental pathology.

Osteoarthritis (OA) and osteoporosis (OP) are historically considered to be inversely correlated but there may be an overlap between the pathophysiology of the two diseases. This study aimed to investigate the subchondral bone microarchitecture and matrix mineralization, and the association between them in OA and OP in relation to the degree of cartilage degeneration. Fifty‐six osteochondral plugs were collected from 16 OA femoral heads. They were graded on a regional basis according to the stages of cartilage degeneration, as evaluated by a new macroscopic and a modified microscopic grading system. Twenty‐one plugs were collected from seven femoral heads with OP. Plugs were scanned by microcomputed tomography and the microarchitectural and mineral properties were obtained for both subchondral plate and trabecular bone. Microarchitecture and material and apparent densities of subchondral bone in OP were similar to regions with early cartilage degeneration but different from regions with advanced cartilage degradation in OA femoral heads. Subchondral trabecular bone was more mineralized than subchondral plate in both OP and OA, and this compartmental difference varied by severity of cartilage degradation. Furthermore, the relationship among trabecular bone volume fraction, tissue mineral density, and apparent bone density was similar in OP and different stages of OA. Subchondral bone microarchitecture and mineral properties in OP are different from OA in a regionalized manner in relation to stages of cartilage degeneration. Both regional and compartmental differences at structural, material, and cellular levels need to be studied to understand the transition of OA subchondral bone from being osteoporotic to sclerotic. [ABSTRACT FROM AUTHOR]

Context. Parental history of osteoporosis is associated with an increased risk of fracture. However, there are not many data on the mechanism of action. Our objective was to determine if heredity influences fracture rate: independently or through the bone mineral density; to identify also the strongest independent risk factors of osteoporotic fractures among our study population. Methods. We processed data of 541 women outpatients with an average age of 55 years, participating in an osteoporosis screening program. Our results confirm that the presence of family history significantly increases fracture prevalence, (37% vs. 17%, p<0.001, OR 2.853, p=0.001) and decreases BMD scores. Fractures occur at higher (better) T and Z-scores. The risk of having T values in the range of (0--1) and Z values in (-1--2) is much higher in the positive group. The logistic regression analysis confirms the BMD-independent influence of heredity on fracture risk. Conclusions. Parental history of osteoporosis negatively affects bone density and significantly increases the incidence of fractures. The latter happens also independently of the bone density values. Timely intervention in these easy-to-detect cases may be the most effective prevention of osteoporotic fractures. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência & Saúde Coletiva is the property of Associacao Brasileira de Pos-Graduacao em Saude Coletiva 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.)

Objectives: To evaluate the effect of ionizing radiation and cariogenic biofilm challenge using two continuous flow models, normal and reduced salivary flow, on the development of initial root-dentin caries lesions. Materials and methods: Microcosm biofilms were grown under two salivary flow rates (0.06 and 0.03 mL min−1) and exposed to 5% sucrose (3 × daily, 0.25 mL min−1, 6 min) dripped over non-irradiated and irradiated root-dentin blocks for up to 7 days. The vibration modes of root dentin, matrix/mineral (M/M), and carbonate/mineral (C/M) ratios were evaluated by FTIR. The mineral density was assessed by micro-CT. Results: With normal salivary flow, FTIR revealed an increase in the organic matrix (amide III) and a decrease in the mineral phase (ν4, ν2 PO43−, AII + ν2 CO32−, C/M) in caries lesions. Irradiated dentin exhibited a reduction in the mineral phase (ν1, ν3 PO43−, ν2 CO32−, C/M). Differences in mineral densities were not significant. With reduced salivary flow, FTIR also revealed increased organic matrix (amide III) for irradiated caries lesions and decrease in mineral phase (v4, v2 PO43−, v2 CO32−, and C/M) in caries lesions. ν1, ν3 PO43− precipitated on the surface of irradiated dentin and a lower mineral density was observed. Conclusions: Initial caries lesions differed between non-irradiated and irradiated dentin and between normal and reduced salivary flow rates. Significant mineral loss with exposure of the organic matrix and low mineral density were observed for irradiated dentin with a reduced salivary flow rate. Clinical relevance: Ionizing radiation associated with a reduced salivary flow rate enhanced the progression of root-dentin caries. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize natal and neonatal teeth using micro-computed tomography. A total of 4 natal and 11 neonatal teeth were used for the analysis. The reconstructed scans were assessed for the maximum enamel/dentin thickness and mineral density (MD). The scanned specimens were 3D reconstructed to qualitatively determine the surface topography. The dentin thickness was two-fold greater than enamel thickness for both natal and neonatal teeth (p < 0.05). The cervical third enamel MD remained undetermined in natal and neonatal teeth. The dentin MD at the cervical third for neonatal teeth was significantly lower than the incisal and middle third dentin (p < 0.05). Similarly, the dentin MD at the cervical third of neonatal teeth was significantly lower than the cervical third dentin MD of natal teeth (p < 0.05). Our qualitative analysis suggests that the cervical thirds of both natal and neonatal teeth are peculiar of an anomalous structure, with neonatal teeth showing an irregular outline. Under the conditions of the present study, it can be concluded that the neonatal teeth studied exhibited a distinguishable aberrant structure compared to the natal teeth. Therefore, the natal teeth unfold as a more organized, three-dimensional structure compared to the neonatal teeth.

Gaucher disease (GD) is caused by pathogenic mutations in GBA1 , the gene that encodes the lysosomal enzyme β-glucocerebrosidase. Despite the existence of a variety of specific treatments for GD, they cannot completely reverse bone complications. Many studies have evidenced the impairment in bone tissue of GD, and molecular mechanisms of bone density alterations in GD are being studied during the last years and different reports emphasized its efforts trying to unravel why and how bone tissue is affected. The cause of skeletal density affection in GD is a matter of debates between research groups. and there are two opposing hypotheses trying to explain reduced bone mineral density in GD: increased bone resorption versus impaired bone formation. In this review, we discuss the diverse mechanisms of bone alterations implicated in GD revealed until the present, along with a presentation of normal bone physiology and its regulation. With this information in mind, we discuss effectiveness of specific therapies, introduce possible adjunctive therapies and present a novel model for GD-associated bone density pathogenesis. Under the exposed evidence, we may conclude that both sides of the balance of remodeling process are altered. In GD the observed osteopenia/osteoporosis may be the result of contribution of both reduced bone formation and increased bone resorption. [ABSTRACT FROM AUTHOR]

Abstract Background Cell behavior is the key to tissue regeneration. Given the fact that most of the cells used in tissue engineering are anchorage-dependent, their behavior including adhesion, growth, migration, matrix synthesis, and differentiation is related to the design of the scaffolds. Thus, characterization of the scaffolds is highly required. Micro-computed tomography (micro-CT) provides a powerful platform to analyze, visualize, and explore any portion of interest in the scaffold in a 3D fashion without cutting or destroying it with the benefit of almost no sample preparation need. Main body This review highlights the relationship between the scaffold microstructure and cell behavior, and provides the basics of the micro-CT method. In this work, we also analyzed the original papers that were published in 2016 through a systematic search to address the need for specific improvements in the methods section of the papers including the amount of provided information from the obtained results. Conclusion Micro-CT offers a unique microstructural analysis of biomaterials, notwithstanding the associated challenges and limitations. Future studies that will include micro-CT characterization of scaffolds should report the important details of the method, and the derived quantitative and qualitative information can be maximized.

Background: This study aimed to compare the efficacies of experimental toothpastes containing functionalized tricalcium phosphate (fTCP) with and without fluoride for in vitro enamel remineralization under pH-cycling conditions. Methods: To create artificial white spot lesions, 36 bovine enamel specimens were immersed in a demineralization solution for 10 days. During pH-cycling for 12 days, the specimens were divided into four groups based on the experimental toothpaste type used: (a) fTCP-free, fluoride-free (fTCP − F −); (b) fTCP-containing, fluoride-free (fTCP + F −); (c) fTCP-free, fluoride-containing (fTCP − F +); and (d) fTCP-containing, fluoride-containing (fTCP + F +). Micro-focus X-ray computed tomography (μCT) scans of all specimens were obtained before demineralization, after demineralization, and after pH-cycling. The mineral density and mineral loss (ΔZ) in the enamel subsurface lesions were measured and the percentage of remineralization (%R) was calculated from ΔZ after demineralization and pH-cycling. One-way ANOVA with Tukey's test was used for statistical analysis of the %R values. The treated enamel surface was investigated via scanning electron microscopy (SEM). Results: The fTCP − F − group presented with the lowest amount of mineral gain after pH-cycling. In contrast, the fTCP + F + group showed the highest degree of remineralization within all lesion parts. The %R was highest in the fTCP + F + group (38.2 ± 7.8, all P < 0.01). SEM revealed the presence of small crystals on the enamel rods in the fTCP + F − and fTCP + F + groups. Conclusions: The experimental toothpaste containing fTCP and fluoride increased remineralization of the artificial enamel subsurface lesions during pH-cycling. Furthermore, fTCP and fluoride appear to act independently on the remineralization of enamel subsurface lesions, although they coexisted in one toothpaste type. Trial registration: This is not a human subject research. [ABSTRACT FROM AUTHOR]

Fracture healing often requires extended convalescence as the bony fragments consolidate into restored viable tissue for load-bearing. Development of interventions to improve healing remains a priority for orthopaedic research. The goal of this study was to evaluate the ability of a naturally occurring matrix of amorphous calcium carbonate to affect fracture healing in an uninstrumented long bone model. Complete transverse fracture was induced in the fibula of mature mice, followed by daily gavage of crushed gastrolith from crayfish at doses of 0 (control), 1 (1 MG), and 5 (5 MG) mg/kg. At Day 17, bones and sera were harvested. Morphologically, the 1 MG treated group had greater bone volume (BV), and both 1 MG and 5 MG had greater tissue volume (TV) than control (p < 0.05), as determined by μCT; BV/TV and mineral density did not yield a statistical difference. Histologically, regional variations in mineralized matrix were evident in all specimens, indicating a broad continuum of healing within the callus. Among serum proteins, bone-specific alkaline phosphatase, indicative of active mineralization, was greater in 5 MG than control (p < 0.05). Sclerostin, an inhibitor of osteogenesis, was lower in 5 MG than control (p < 0.05), also suggestive of enhanced healing. An increase in bone volume, tissue volume and cellular signaling for osteogenesis at 17 days following fibula fracture in this mouse model suggests that gastrolith treatment holds potential for improving fracture healing. Further study at subsequent time points is warranted to determine the extent to which the increase in callus size with gastrolith treatment may accelerate restoration of tissue integrity. [ABSTRACT FROM AUTHOR]

Objective: The estimation of time of death or the determination of the postmortem interval (PMI) is one of the most important issues in forensic medicine and odontology. However, evaluation of bone and dental hard tissues in PMI could be challenging due to the lack of objective methods with high accuracy. In this respect, micro-CT analysis which has not been used for postmortem evaluation would be beneficial in evaluating hard tissues such as bones and teeth. Therefore, the aim of the present study was to determine the alterations in the hard dental tissue, mineral density of enamel, and the surface abrasion of hard dental tissues of rats in the PMI period with a relatively novel method, micro-CT. Methods: The present study included 60 female Wistar rats which were divided into six study groups. The rats were sacrificed at the baseline and were left into nature putrefaction process. The study groups were created based on the PMI period as week—0, week—1, week—2, week—4, week—8, and week—12, which included 10 rats in each group. All hemi-mandibles were collected in the determined timelines and the micro-CT analysis was carried out on each group. Mineral density of enamel and the surface abrasion of hard dental tissues were determined. Results: The enamel and cement thickness remained the same in the examined PMI periods. Mineral density of the enamel tissues were also similar until the 8th week but the decrease was significant at 12th week (2.313 gHAp cm3). Surface abrasion of the dental tissues on weeks 4, 8, and 12 were 0.006, 0.024, and 0.024 mm, respectively. Conclusion: The present study indicated that surface abrasion and enamel mineral density evaluation via micro-CT can be considered as objective and precise parameters in PMI evaluation in forensic medicine and odontology. [ABSTRACT FROM AUTHOR]

Aims and Objectives: The aim of this study was to evaluate the effectiveness of three different caries excavation methods using micro-computed tomography (micro-CT). Materials and Methods: Fifteen freshly extracted human molar teeth with occlusal dentinal caries were selected. The teeth were sectioned longitudinally into two halves and were randomly divided into three groups (n = 10) depending on the caries removal technique: Group 1: tungsten carbide (TC) bur, Group 2: cerabur (CB), and Group 3: Excavus (EX) tipEX). A preoperative micro-CT scan of all the samples was taken. The caries excavation procedures were carried out followed by postoperative micro-CT scan. The preoperative and postoperative scans of each tooth were analyzed for caries removal effectiveness (CRE), mineral density (MD), and minimal invasiveness potential (MIP) using Avizo 9.4 software (Thermo Fisher Scientific, Germany). Statistical analysis was conducted by applying three-way analysis of variance and independent sample t-test using the Statistical Package for the Social Sciences software, version 20.0 (IBM Corporation, USA). Results: Among the three groups, the TC group had the smallest RC/IC (residual caries/initial caries) ratio, highest mean MD at the cavity floor, and highest MIP. The EX group significantly had the highest RC/IC, lowest mean MD, and lowest MIP. Both the CRE and MIP parameters of CB group were acceptable (RC/IC = 0.08, mean MD = 1.09 g/cm³, and MIP = 1.09). Conclusion: As compared with the three excavation methods, CBs can be considered as an alternative to TC burs because of its MIP and complete removal of infected carious dentin. [ABSTRACT FROM AUTHOR]

Abstract Background To investigate the effect of intra-articular injection of Chitosan (Cs) added to hyaluronic acid (HA) on subchondral bone during osteoarthritis (OA), microarchitectural parameters and mineral density were measured in a rabbit model of early OA. A novel hybrid hydrogel adding reacetylated Cs of fungal origin to HA was compared to high molecular weight HA commercial formulation. Method Eighteen rabbits underwent unilateral anterior cruciate ligament transection (ACLT) and were divided into three groups (Saline-group, HA-group and Hybrid-group) depending on the intra-articular injection compound. Eight contralateral knees were used as non-operated controls (Contralateral-group). Micro-computed tomography was performed six weeks post-ACLT to study subchondral bone microarchitectural parameters and mineral density at an early stage of OA development. Results Cartilage thickness mean value was reduced only in Saline-group compared to Contralateral-group. When the Hybrid-group was compared to Saline-group, subchondral bone microarchitectural parameters (trabecular thickness and trabecular bone volume fraction) were significantly changed; subchondral bone plate and trabecular bone mineral densities (bone mineral density and tissue mineral density) were reduced. When the Hybrid-group was compared to HA-group, subchondral bone microarchitectural parameters (subchondral plate thickness and trabecular thickness) and trabecular bone mineral densities (bone mineral density and tissue mineral density) were significantly decreased. Conclusion Conclusion: Compared to HA alone, the novel hybrid hydrogel, constituted of Cs added to HA, enhanced microarchitectural parameters and mineral density changes, leading to subchondral bone loss in a rabbit model of early experimental OA.

Silver diamine fluoride (SDF) is a cost-effective method for arresting active dental caries. However, the limited cooperation of patients may lead to an SDF application time that is shorter than the recommended 1–3 min for carious lesions. Therefore, the aim of this study was to assess the effect of different application times of SDF on the degree of mineral precipitation in demineralized dentin. Demineralized dentin specimens from permanent maxillary molars were treated by applying 38% SDF for 30, 60, or 180 s. Water was applied in the control group. The specimens were immersed in simulated body fluid for 2 weeks, and the mineral precipitation in demineralized dentin was then analyzed using FTIR-ATR, SEM-EDX, and synchrotron radiation X-ray tomographic microscopy (SRXTM). The FTIR-ATR results showed a significant increase in mineral precipitation in the 180 s group after 1 week. However, after 2 weeks, the SRXTM images indicated comparable mineral density between the 30, 60, and 180 s groups. The precipitation of silver chloride and calcium phosphate crystals that occluded dentinal tubules was similar in all experimental groups. In conclusion, an application time of either 30, 60, or 180 s promoted a comparable degree of mineral precipitation in demineralized dentin.

Objective: The objective of this study was to compare the remineralizing effect of sodium fluoride (NaF) mouth rinse or NaF gel as an adjunct to NaF dentifrice on incipient caries-like lesions in an in situ cross-over design study, with three sessions of 30 days each. Materials and methods: Orthodontic brackets with artificial demineralized enamel slabs were attached to the upper first molars of 12 participants. A set of 3 test specimens from the same tooth was randomly assigned to each participant and allocated into three 30-day sessions: 1) brushing with 0.22% NaF dentifrice 2 times/day (F dentifrice), 2) brushing with 0.22% NaF dentifrice 2 times/day+ rinsing with 0.05% NaF before bedtime (F mouth rinse), 3) brushing with 0.22% NaF dentifrice 2 times/day + brushing with 1.1% NaF gel before bedtime (F brush-on gel). The mineral gain and lesion depth of the specimens were evaluated by micro-computed tomography. Results: The mean mineral gain from the NaF mouth rinse and the NaF brush-on gel was similar, but greater than that from the NaF dentifrice (p < .05). The NaF brush-on gel yielded the greatest mean depth of remineralization (168 µm), followed by the NaF mouth rinse (144 µm). Both depths were significantly greater than that of the NaF dentifrice (84 µm) (p < .05). Conclusions: Both 0.05% NaF mouth rinse and 1.1% NaF brush-on gel, used at bedtime, increased incipient caries-like lesion remineralization in situ in combination with brushing with NaF dentifrice twice a day. [ABSTRACT FROM AUTHOR]

Bone remodeling is a physiological phenomenon coupling resorption and formation processes that are mainly mediated by osteoclasts and osteoblasts, in response to mechanical stimuli transduced by osteocytes to biochemical signals activating the bone multicellular unit. Under normal loading conditions, bone resorption and formation are balanced by a homeostasis process. When bone is subjected to overstress, microdamaging occurs, which induces a modification of the structural integrity and microarchitecture. This has drawn significant attention to the mechanical properties of bone. In this context, the current study has been carried out with the aim of numerically investigating the impact of the mechanical properties on the remodeling process of the trabecular bone under cyclic loading, highlighting the effects of different values of the mineral density and the Young's modulus. This was performed using a mechanobiological model, coupling mechanical and biological approaches, allowing to numerically simulate the effect of the selected parameters for a 20-year-period of cyclic loading for 2D and 3D models of a human femur head. The current work is an explorative numerical study, and the obtained results revealed the changes in the overall stiffness of the bone according to the mechanical properties. [ABSTRACT FROM AUTHOR]

Objectives: The present study was performed to investigate the mineral density distribution in enamel and dentin for both permanent and primary teeth and to establish the standard density per tooth type using micro-computed tomography (CT).Methods: Fifty-seven extracted human teeth (37 permanent, 20 primary) were evaluated in the present study. The enamel and dentin mineral densities in the extracted teeth were measured using micro-CT. Cubic regression curves were used to determine the mineral density distribution in the enamel and dentin for each tooth type.Results: The mean values, distributions, and regression equations of the mineral densities were obtained. The mean mineral density values for permanent enamel and dentin were significantly higher than those for their primary counterparts for each tooth type.Conclusions: In the present study, we demonstrated the distribution of mineral density in sound enamel and dentin and attempted to determine the standard mineral density for each tooth type using micro-CT. The mineral density distributions found in this study contribute to our understanding of the mechanical properties of enamel and dentin. A positive correlation suggests that the systemic bone mineral density could be predicted based on the analysis of exfoliated teeth, such as in patients with hypophosphatasia. The present results may be useful in establishing a numerical standard for the mechanism involved in root fracture and for early detection of root fracture risk. [ABSTRACT FROM AUTHOR]

The rat vertebrae is a good model to study bone regeneration after implantation of biomaterials used to treat bone loss, a major problem in oral and dental surgery. However, the precise characterization of bone microstructures in the rat vertebrae has not been reported. Therefore, the aim of this study was to achieve the complete analysis of such bone, at different scales , in order to have a clear model of healthy bone for comparison with regenerated bone. In order to image the cortical bone of rat caudal vertebra, confocal Raman microscopy was combined with high resolution X-ray micro computed tomography (micro-CT), with scanning electron microscopy (SEM) using backscatter electron imaging and with more conventional histology coloration techniques. SEM and Raman microscopy were done in various regions of the cortical bone corresponding to external, middle and internal areas. The spongy bone was imaged in parallel. Micro-CT was performed on the whole vertebra to monitor the network of haversian canals in the cortical bone. Osteonic canals characteristics, and relative chemical composition were analysed in several regions of interest, in cortical and spongy bone. Five rats were included in this study. On micro-CT images, differences in intensity were observed in the cortical bone, substantiated by SEM. Chemical analysis with Raman spectra confirmed the difference in composition between the different regions of the cortical and spongy bone. PCA and k-mean cluster analysis separated these groups, except for the external and middle cortical bone. Peak intensity ratio confirmed these results with a CO 3 to ν 2 PO 4 ratio significantly different for the internal cortical bone. Grayscale images stack extracted from micro-CT showed that global architecture of cortical bone was characterized by a dense and complex network of haversian osteonic canals, starting from the surface towards the vertebrae center. The mean diameter of the canals was 18.4 µm (SD 8.6 µm) and the mean length was 450 µm (SD 152 µm). Finally, Raman reconstructed images of the lamellar bone showed an enlargement of the lamellar layer width, both in circumferential lamellar bone and around haversian canals. Micro-CT and confocal Raman microscopy are good tools to complete classical analysis using optical and electron microscopy. The results and measurements presented in a rat model known for its small inter-individual differences provide the main characteristics of a mature bone. This study will allow the community working on this rat vertebrate model to have a set of characteristics, in particular on the structure of the haversian canals. [ABSTRACT FROM AUTHOR]

Modeling and remodeling induce significant changes of bone structure and mechanical properties with age. Therefore, it is important to gain knowledge of the processes taking place in bone over time. The rat is a widely used animal model, where much data has been accumulated on age-related changes of bone on the organ and tissue level, whereas features on the nano- and micrometer scale are much less explored. We investigated the age-related development of organ and tissue level bone properties such as bone volume, bone mineral density, and load to fracture and correlated these with osteocyte lacunar properties in rat cortical bone. Femora of 14 to 42-week-old female Wistar rats were investigated using multiple complementary techniques including X-ray micro-computed tomography and biomechanical testing. The body weight, femoral length, aBMD, load to fracture, tissue volume, bone volume, and tissue density were found to increase rapidly with age at 14–30 weeks. At the age of 30–42 weeks, the growth rate appeared to decrease. However, no accompanying changes were found in osteocyte lacunar properties such as lacunar volume, ellipsoidal radii, lacunar stretch, lacunar oblateness, or lacunar orientation with animal age. Hence, the evolution of organ and tissue level properties with age in rat cortical bone is not accompanied by related changes in osteocyte lacunar properties. This suggests that bone microstructure and bone matrix material properties and not the geometric properties of the osteocyte lacunar network are main determinants of the properties of the bone on larger length scales.

Abstract This experiment was conducted to evaluate the effect of in-ovo ascorbic acid (AA) injection on the bone development of broilers submitted to heat stress during incubation and rearing. One thousand (1,000) Cobb(r)fertile broiler eggs were randomly distributed according to the weight into five incubators, with 200 eggs per incubator. The incubation treatments were: eggs not injected with AA and incubated at 37.5°C; eggs not injected with AA and incubated at 39°C; and eggs injected with 6 µg AA/100 µL water prior to incubation and incubated at 39ºC. The hatched birds were reared at three different house temperatures: cold, thermoneutral, or and hot. The high incubation temperature negatively influenced broilers' bone characteristics. The femur of the birds hatched from eggs incubated at 39°C and injected with AA presented lower shaft mineral density, lower maximum force and lower elongation at maximum force. Their tibia presented reduced mineral density at the proximal and distal epiphysis. In-ovo AA injection of eggs incubated at high temperature did not minimize the negative effects of high rearing temperature on the performance andbone development of broiler chickens reared until 42 days of age.