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Objectives: To evaluate the associations between the cortical bone‐to‐implant contact (CBIC), bone microstructure derived from cone‐beam computed tomography (CBCT), and the primary stability of the implant. Materials and Methods: Twenty‐two patients with 65 implants were enrolled in this study. The peak insertion torque values (ITVs) were measured during implant insertion, and the implant stability quotient (ISQ) values were measured immediately after implant placement and 3 months after surgery. The profiles of the peri‐implant bone structure were outlined using the volumetric reconstruction of the CBCTs and superimposition of the virtual models, and the features of CBIC and bone microstructure parameters were measured. The linear mixed effects model and generalized estimating equation were used to explore the predictors for implant primary stability. Results: The average ITV, baseline, and secondary ISQ values were 31.44 ± 6.54 N·cm, 73.34 ± 7.39, and 80.32 ± 4.58, respectively. Statistically significant correlations were found between ITV and surface area of CBIC (r =.340, p =.006), bone volume fraction (r =.294, p =.017), and bone surface fraction (r = −.278, p =.039). Implants with buccolingual CBIC had a higher ITV than implants without CBIC (p =.016). None of the parameters were associated with baseline and secondary ISQ values in generalized estimating equation analysis (all p >.05). Conclusions: Within the limitations of the study, preoperative CBCT measurements might enable the prediction of ITV and therefore of implant primary stability values. [ABSTRACT FROM AUTHOR]

Summary: This meta‐analysis aimed to assess the effect of Roux‐en‐Y gastric bypass (RYGB) on three‐dimensionally assessed volumetric bone mineral density (vBMD) with the effect of time on these changes, on bone quality, and the agreement of dual‐energy X‐ray absorptiometry (DXA) with quantitative computed tomography (QCT) or high‐resolution peripheral QCT (HR‐pQCT) estimates of bone loss. We searched PubMed, Web of Science, Cochrane, Scopus, and EBSCO. Longitudinal studies on adults undergoing RYGB in which vBMD was assessed by QCT or HR‐pQCT with ≥6 months follow‐up were included. Total hip (TH) changes were reported in four studies, lumbar spine (LS) in eight, radius in eight, and tibia in seven. Significant post‐RYGB vBMD reductions occurred at all skeletal sites analyzed. Meta‐regression revealed that time post‐RYGB was significantly associated with vBMD deterioration in all skeletal sites except at the TH. RYGB also led to significant deterioration on bone quality. DXA underestimated LS and overestimated TH bone losses post‐RYGB. In conclusion, RYGB was associated with significant vBMD loss, which makes screening of bone mass progression by three‐dimensional technology a crucial clinical issue to prevent fracture risk and osteoporosis. [ABSTRACT FROM AUTHOR]

The need for a substitute for allograft and autograft is rising as bone graft surgeries exceed available supplies. We investigated the efficacy of the low‐molecular weight marine bioactive compound fucoidan (FUC) on bone regeneration and implant fixation in seven female sheep, as FUC has shown great promise as a bone substitute. Titanium implants were inserted bilaterally in the distal femurs to test three hydroxyapatite/fucoidan (HA/FUC) groups and compared to allograft. The HA was coated with either 500 or 1500 μg of FUC, obtained by microwave‐assisted chemical extraction, or 500 μg of FUC obtained by an enzyme‐assisted extraction method. The concentric 2‐mm gap around the implant was filled with either one of the HA/FUCs or allograft from the donor sheep. After 12 weeks, implant–bone blocks were harvested and divided into three parts for mechanical push‐out testing, immunohistochemistry, and micro‐CT and histomorphometry. Pronounced bone formations were observed by micro‐CT and histomorphometry in all groups, but higher bone volume fractions were seen in the allograft group compared to the three HA/FUC groups. The trabecular thickness, trabecular separation, and architectural anisotropy were all significantly higher in the allograft group compared to the three HA/FUC groups. In conclusion, adequate bone formation was observed in all groups, although the bone formation was significantly greater in the allograft group. Also, no significant differences existed in the shear mechanical properties between groups, suggesting that the combination of HA and FUC can achieve a similar fixation strength to allograft in this model. [ABSTRACT FROM AUTHOR]

Fiber reinforced thermoplastic composites are limited due to poor interfacial bonding between the nonpolar/nonreactive polymer matrix and fiber surface. Recently, a concept of controlled mechanical interlocking between fiber and matrix surface was proposed to improve the interfacial bonding in fiber reinforced thermoplastic composites. Study results show promising performance of the approach under static loading conditions. In this work, we study the effect of strain rate on the interfacial bonding behavior under dynamic loading conditions. A parametric study of the strain rate effect is performed for which different surface microarchitectures of a glass/polypropylene composite system are considered. A three network model is implemented for modeling mechanical behavior of polymer, which is calibrated using a set of stress–strain curves experimentally obtained at various strain rates. The strength calculations address both polymer fracture and detachment of the polymer matrix from the anchoring sites. The results show that under the strain rates ranging from 2 × 10−4/s to 2 × 10−1/s, even without any interfacial friction or adhesion, the interfacial shear strength could achieve close to 70% of the theoretical strength of perfect matrix‐fiber bonding. It is observed that, while strain rate has appreciable effects on the fiber/matrix interfacial strength and can cause change of failure mode in some cases; its influence also depends on the geometry of the anchoring sites. Moreover, there is an optimal geometric configuration at which maximum failure strength is achieved. Graphic charts showing the dependency of interfacial strength on the strain rate and geometric configuration parameters are obtained. [ABSTRACT FROM AUTHOR]

Architected materials can exhibit mechanical properties that do not occur with ordinary solids. By integrating hierarchy and size effects, microarchitected metamaterials fabricated by two‐photon lithography with a metallic or ceramic coating can be ultrastrong but lightweight. However, the attainment of both strength and ductility is generally mutually exclusive. Inspired by the Pantheon dome in Rome, which can withstand high load while keeping low density, microarchitected domes with a gradient helix are designed and deposited in a hierarchical nanostructured aluminum film with ultrahigh strength and considerable plasticity. Despite having a thick coating, which usually causes catastrophic collapse, the thick‐walled metallic dome shows recoverability during compression. The compressive strength increases to 73 times that of current ductile‐like microlattices, leading to the metamaterial occupying the domain of the material property space that is hitherto empty. Detailed in situ experimental and computational work reveals the graceful (noncatastrophic) failure due to the helical twisting and plastic flow in the supra‐nanomaterial. It is a promising method of suppressing brittle failure via a combination of architectural and material design. It can be used to impart enhanced functionality, making programmable stiffness, and tailored energy absorption all possible. [ABSTRACT FROM AUTHOR]

Objectives: Macroscopic entheseal forms show two main features: predominant signs of bony formation or resorption. To understand the development of these forms, we investigated microarchitectural differences between the macroscopic proliferative and resorptive forms of the gluteus maximus enthesis. Materials and Methods: The macromorphological analysis of entheseal changes (EC) was based on the Villotte, visual scoring system for fibrous entheses. Gluteal tuberosity specimens of different stages of Villote's system were harvested from 16 adult males derived from an archaeological context and scanned using microcomputed tomography. Results: The microarchitectural analyzes of cortical bone demonstrated a trend of higher porosity in the resorptive compared to the proliferative phase in Stage B, whereas a 30% porosity reduction was detected in the resorptive compared to proliferative phase of Stage C. In terms of the trabecular bone between the resorptive and proliferative entheseal phases, there was a trend of increased connectivity density, whereas the structural model index decreased in B and increased in C. The assessment of the entire specimen showed an increase in porosity from the proliferative to the resorptive phase in the Stage B, in contrast to a decrease in the Stage C. Discussion: The results suggest that from an initial flat entheses, two directions of EC development are possible: (a) a bony prominence may form and, subsequently, it is subjected to trabecularization of the cortical bone inside the prominence, such cortical trabecularization can lead to visible porosity on the cortical external surface; (b) the cortical bone defect may develop with the regular underlying cortical bone. [ABSTRACT FROM AUTHOR]

Summary: Objectives: To determine sex‐specific associations between insulin resistance and bone parameters measured by peripheral quantitative computed tomography in overweight and obese community‐dwelling older adults. Study design: Cross‐sectional study of 79 community‐dwelling overweight and obese adults (mean ± SD age 62.8 ± 7.9 years; body mass index 32.3 ± 6.1 kg/m2; 58% women). Main outcome measures: Peripheral quantitative computed tomography assessed distal radius and tibia trabecular volumetric bone mineral density (vBMD) and proximal radius and tibia cortical vBMD, periosteal circumference, endosteal circumference and stress‐strain index. The Homeostatic Model Assessment of Insulin Resistance (HOMA‐IR) score was calculated from fasting glucose and insulin values. Lean mass was assessed using dual‐energy X‐ray absorptiometry. Total minutes of moderate and vigorous physical activity (MVPA) were calculated using the Active Australia Survey. Results: Men and women in this cohort had no significant differences in fasting glucose and insulin concentrations, HOMA‐IR values and diabetes prevalence (all P > 0.05). In women, HOMA‐IR was positively correlated with proximal radius periosteal and endosteal circumference (r = 0.331; P = 0.034 and r = 0.325; P = 0.038, respectively). These associations became nonsignificant in multivariable regression analyses; however, HOMA‐IR was negatively associated with proximal radius cortical vBMD (B = −4.79; 95% CI −8.66, −0.92) after adjusting for age, lean mass and MVPA. All associations between HOMA‐IR and bone parameters became nonsignificant in a sensitivity analysis excluding individuals with diabetes, or self‐reported use of glucose‐lowering medications. There were no associations between HOMA‐IR and bone parameters in men. Conclusions: Homeostatic Model Assessment of Insulin Resistance was negatively associated with radial cortical vBMD in overweight and obese older women, but not in men. Further studies are needed to clarify sex‐specific associations between insulin resistance and bone health in overweight and obese older adults. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to investigate age‐related changes in the morphological, biochemical and mechanical properties of articular cartilage (AC) and subchondral bone in the rat tibial plateau. Female Wistar rats were grouped according to age (1, 3, 5, 7, 9, 11, 13, 15, 16 and 17 months, with 10 rats in each group). The ultrastructures, surface topographies, and biochemical and mechanical properties of the AC and subchondral bone in the knee joints of the rats were determined through X‐ray micro‐tomography, histology, immunohistochemistry, scanning electron microscopy (SEM), atomic force microscopy and nanoindentation. We found that cartilage thickness decreased with age. This decrease was accompanied by functional condensation of the underlying subchondral bone. Increased thickness and bone mineral density and decreased porosity were observed in the subchondral plate (SP). Growth decreased collagen II expression in the tibial cartilage. The arrangement of trabeculae in the subchondral trabecular bone became disordered. The thickness and strength of the fibers decreased with age, as detected by SEM. The SP and trabeculae in the tibial plateau increased in roughness in the first phase (1–9 months of age), and then were constant in the second phase (11–17 months of age). Meanwhile, the roughness of the AC changed significantly in the first phase (1–9 months of age), but the changes were independent of age thereafter. This study gives a comprehensive insight into the growth‐related structural, biochemical and mechanical changes in the AC and subchondral bone. The results presented herein may contribute to a new understanding of the pathogenesis of age‐related bone diseases. [ABSTRACT FROM AUTHOR]

Purpose: Osteoporosis associated with reduced bone mineral density (BMD) and microarchitectural changes puts patients at an elevated risk of fracture. Modern multidetector row CT (MDCT) technology, producing high spatial resolution at increasingly lower dose radiation, is emerging as a viable modality for trabecular bone (Tb) imaging. Wide variation in CT scanners raises concerns of data uniformity in multisite and longitudinal studies. A comprehensive cadaveric study was performed to evaluate MDCT‐derived Tb microarchitectural measures. A human pilot study was performed comparing continuity of Tb measures estimated from two MDCT scanners with significantly different image resolution features. Method: Micro‐CT imaging of cadaveric ankle specimens ( n = 25) was used to examine the validity of MDCT‐derived Tb microarchitectural measures. Repeat scan reproducibility of MDCT‐based Tb measures and their ability to predict mechanical properties were examined. To assess multiscanner data continuity of Tb measures, the distal tibias of 20 volunteers ( age : 26.2 ± 4.5 Y , 10 F) were scanned using the Siemens SOMATOM Definition Flash and the higher resolution Siemens SOMATOM Force scanners with an average 45‐day time gap between scans. The correlation of Tb measures derived from the two scanners over 30% and 60% peel regions at the 4% to 8% of distal tibia was analyzed. Results: MDCT‐based Tb measures characterizing bone network area density, plate‐rod microarchitecture, and transverse trabeculae showed good correlations ( r ∈ 0.85 , 0.92) with the gold standard micro‐CT‐derived values of matching Tb measures. However, other MDCT‐derived Tb measures characterizing trabecular thickness and separation, erosion index, and structure model index produced weak correlation ( r < 0.8) with their micro‐CT‐derived values. Most MDCT Tb measures were found repeatable ( ICC ∈ 0.94 , 0.98). The Tb plate‐width measure showed a strong correlation (r = 0.89) with experimental yield stress, while the transverse trabecular measure produced the highest correlation (r = 0.81) with Young's modulus. The data continuity experiment showed that, despite significant differences in image resolution between two scanners (10% MTF along xy‐plane and z‐direction – Flash: 16.2 and 17.9 lp/cm; Force: 24.8 and 21.0 lp/cm), most Tb measures had high Pearson correlations (r > 0.95) between values estimated from the two scanners. Relatively lower correlation coefficients were observed for the bone network area density (r = 0.91) and Tb separation (r = 0.93) measures. Conclusion: Most MDCT‐derived Tb microarchitectural measures are reproducible and their values derived from two scanners strongly correlate with each other as well as with bone strength. This study has highlighted those MDCT‐derived measures which show the greatest promise for characterization of bone network area density, plate‐rod and transverse trabecular distributions with a good correlation (r ≥ 0.85) compared with their micro‐CT‐derived values. At the same time, other measures representing trabecular thickness and separation, erosion index, and structure model index produced weak correlations (r < 0.8) with their micro‐CT‐derived values, failing to accurately portray the projected trabecular microarchitectural features. Strong correlations of Tb measures estimated from two scanners suggest that image data from different scanners can be used successfully in multisite and longitudinal studies with linear calibration required for some measures. In summary, modern MDCT scanners are suitable for effective quantitative imaging of peripheral Tb microarchitecture if care is taken to focus on appropriate quantitative metrics. [ABSTRACT FROM AUTHOR]

The posteromedial quadrant of the radial head is known to be different from the other quadrants. However, the explanation of this unique anatomical feature remains elusive. Hence, this study was designed to address this unique anatomical variance using three-dimensional μ CT (micro-computed tomography) analysis. Nine fresh cadaveric radial heads were scanned using μ CT. Three-dimensional subchondral bone and cartilage models were rendered. Both models were separated into the four quadrants at both the periphery (rim) and the articulating dish (fovea): anteromedial ( AM), posteromedial ( PM), posterolateral ( PL), and anterolateral ( AL). Each quadrant was analyzed in terms of (1) subchondral bone porosity ( SBP), (2) mean subchondral bone thickness ( MSBT), and (3) mean cartilage thickness ( MCT). There was a significant difference between the fovea and the rim in terms of its microarchitectural features. Although within the fovea, the PM quadrant did not differ significantly from the other quadrants, a significant difference was found within the rim. In terms of SBP, PM, AM, PL and AL were calculated as 33, 37, 36 and 35%, respectively. In terms of MSBT, PM, AM, PL and AL were calculated as 0.11, 0.10, 0.09, and 0.09 mm, respectively. In terms of MCT, PM, AM, PL and AL were calculated 1.09, 0.81, 0.84 and 0.83 mm, respectively. The PM corner of the radial head between the 8 and 9 o'clock positions, was beveled. This might explain why the PM quadrant of the rim differed significantly from the other quadrants in terms of its microarchitectural features. [ABSTRACT FROM AUTHOR]

Early fixation of total joint arthroplasties is crucial for ensuring implant survival. An alternative bone graft material in revision surgery is needed to replace the current gold standard, allograft, seeing that the latter is associated with several disadvantages. The incubation of such a construct in a perfusion bioreactor has been shown to produce viable bone graft materials. This study aimed at producing larger amounts of viable bone graft material (hydroxyapatite 70% and β-tricalcium-phosphate 30%) in a novel perfusion bioreactor. The abilities of the bioreactor-activated graft material to induce early implant fixation were tested in a bilateral implant defect model in sheep, with allograft as the control group. Defects were bilaterally created in the distal femurs of the animals, and titanium implants were inserted. The concentric gaps around the implants were randomly filled with either allograft, granules, granules with bone marrow aspirate or bioreactor-activated graft material. Following an observation time of 6 weeks, early implant fixation and bone formation were assessed by micro-CT scanning, mechanical testing, and histomorphometry. Bone formations were seen in all groups, while no significant differences between groups were found regarding early implant fixation. The microarchitecture of the bone formed by the synthetic graft materials resembled that of allograft. Histomorphometry revealed that allograft induced significantly more bone and less fibrous tissue ( p < 0.05). In conclusion, bone formation was observed in all groups, while the bioreactor-activated graft material did not reveal additional effects on early implant fixation comparable to allograft in this model. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2465-2476, 2017. [ABSTRACT FROM AUTHOR]

Objectives Parallel with body growth and development, bone structure in non-adults is reorganized to achieve the particular design observed in mature individuals. We traced the changes in three-dimensional trabecular microarchitectural design during the phases of locomotor maturation to clarify how human bone adapts to mechanical demands. Materials and Methods Micro-CT was performed on biomechanically-relevant subregions of the proximal femur (medial, intermediate and lateral neck regions, intertrochanteric region, metaphyseal region) from early postnatal period to late childhood. Results Developmental patterns of trabecular microarchitecture showed that gestationally overproduced bone present at birth underwent the most dramatic reduction during the first year, followed by a reversing trend in some of the quantitative parameters (e.g., bone volume fraction, trabecular anisotropy). Certain regional anisotropy already present at birth is further accentuated into the childhood suggesting an adaptation to differential loading environments. Trabecular eccentricity in the femoral neck was particularly accentuated during childhood, giving the medial neck-the site mostly loaded in walking-superior microarchitectural design (high bone volume fraction and anisotropy, the earliest appearance and predominance of plate- and honeycomb-shaped trabeculae). Discussion While providing quantitative data on how bone microarchitecture adapts to increasing mechanical demands occurring during the phases of locomotor maturation, the study reveals how regional anisotropy develops in the proximal femur to ensure a functional and competent bone structure. Decomposing the region-specific patterns of bone mass accrual is important in understanding skeletal adaptations to bipedalism, as well for understanding why fractures often occur location-dependent, both in pediatric and elderly individuals. [ABSTRACT FROM AUTHOR]

Fracture risk is heightened in patients with both type 1 diabetes (T1D) and type 2 diabetes (T2D). Although bone mineral density by dual-energy X-ray absorptiometry is decreased in T1D, it is paradoxically increased with T2D. To predict fracture risk, the Fracture Risk Assessment Tool (FRAX) can be used in diabetes patients, albeit with refinement. Skeletal abnormalities in diabetes include alterations in microarchitecture in T1D and T2D as well as compromised impact microindentation in T2D. Changes in bone microvasculature, advanced glycation end product accumulation, and bone formation may underlie these findings. When fractures occur in T1D and T2D, consequences are worse than in nondiabetic patients with regard to both morbidity and mortality. With regard to treatment, antiresorptive osteoporosis therapies appear to be effective in the setting of diabetes. [ABSTRACT FROM AUTHOR]

ABSTRACT The parameters of a micro-computed tomography (μCT) scan, including whether a bone is imaged in vivo or ex vivo, determine the quality of the resulting image. In turn, this impacts the accuracy of the trabecular and cortical outcomes. The absolute impact of μCT scanning at different voxel sizes and whether the sample is imaged in vivo or ex vivo on the morphological outcomes of the proximal tibia in the rat is unknown. The right proximal tibia of 6-month-old Sham-control and ovariectomized (OVX) rats ( n = 8/group) was scanned using μCT (SkyScan 1176, Bruker, Kontich, Belgium) using three sets of parameters (9 μm ex vivo, 18 μm ex vivo, 18 μm in vivo) to compare the trabecular and cortical outcomes. Regardless of scan protocols, differences between Sham and OVX groups were observed as expected. At a voxel size of 18 μm, scanning in vivo or ex vivo had no effect on any of the outcomes measured. However, compared to a 9 μm voxel size scan, imaging at 18 μm resulted in significant underestimation of the connectivity density ( p < 0.05) of the trabecular bone and a significant overestimation ( p < 0.05) of the trabecular indices (trabecular thickness, degree of anisotropy) and of the cortical indices (cortical bone area, cortical area fraction, cortical thickness) in both Sham and OVX rats. These results suggest the benefit to scanning the proximal tibia of rats at a voxel size as low as 9 μm, although considerations must be made for the increased acquisition time, anesthesia, animal welfare, and radiation exposure associated with lower voxel size in vivo scanning. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1690-1698, 2017. [ABSTRACT FROM AUTHOR]

Purpose: To use 7T magnetic resonance imaging (MRI) to determine how trabecular bone microarchitecture varies at the epiphysis, metaphysis, and diaphysis of the distal radius.Materials and Methods: The distal radius of 24 females (mean age = 56 years, range = 24-78 years) was scanned on a 7T MRI using a 3D fast low-angle shot sequence (0.169 × 0.169 × 1 mm). Digital topological analysis was applied at the epiphysis, metaphysis, and diaphysis to compute: total trabecular bone volume; trabecular thickness, number, connectivity, and erosion index (a measure of network resorption). Differences and correlations were assessed using standard statistical methods.Results: The metaphysis and epiphysis had 83-123% greater total bone volume and 14-16% greater trabecular number than the diaphysis (both P < 0.0001). The erosion index was significantly higher at the diaphysis than the metaphysis and epiphysis (both P < 0.01). The most elderly volunteers had lower trabecular number (<66 years mean 0.29 ± 0.01; ≥66 years, 0.27 ± 0.02, P < 0.05) and higher erosion index (<66 years mean 1.18 ± 0.17; age ≥66 years, mean 1.42 ± 0.46, P < 0.05) at the epiphysis; differences not detected by total trabecular bone volume.Conclusion: 7T MRI reveals trabecular bone microarchitecture varies depending on scan location at the end-of-bone, being of overall higher quality distally (epiphysis) than proximally (diaphysis). Age-related differences in trabecular microarchitecture can be detected by 7T MRI. The results highlight the potential sensitivity of 7T MRI to microarchitectural differences and the potential importance of standardizing scan location for future clinical studies of fracture risk or treatment response.Level Of Evidence: 3 J. Magn. Reson. Imaging 2017;45:872-878. [ABSTRACT FROM AUTHOR]

Insoluble cues from a cell's surrounding microenvironment have increasingly been shown to be important regulators of cell behavior. The microarchitecture of biomaterials used for 3D cell encapsulation, however, is often underappreciated as an important insoluble factor guiding cell activity. In this review, we illustrate that the subcellular physical features of a scaffold influence a range of cell behaviors, including morphology, cytoskeletal organization, migration, matrix remodeling, and long-range force transmission. We emphasize that the microarchitecture of stromal extracellular matrix (ECM)-specifically the fact that it consists of a network of long interconnecting fibers with micron and nanometer-sized diameters-is an important determinant of how cells naturally interact with their surrounding matrix and each other. Synthetic biomaterials with a microarchitecture similar to stromal ECM can support analogous cellular responses, suggesting that this fibrous microarchitecture is a key regulator of these cell behaviors. Drawing upon examples from in vitro, in silico, and in vivo studies, we compare these behaviors in fibrous matrices to those of cells cultured within nanoporous matrices (e.g., alginate and PEG gels) as well as macroporous scaffolds to highlight key differences in the cellular response to each type of microarchitecture. Understanding how microarchitecture affects cell behavior can lead to more efficient biomaterial selection when designing tissue engineered scaffolds for therapeutic applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 640-661, 2017. [ABSTRACT FROM AUTHOR]

In this paper, the authors propose two approaches that employ spin transfer torque random access memory (STTRAM) in the design of the register file, an important part of embedded processors. However, STTRAM suffers from both endurance and latency in the write operation. Consequently, employing STTRAM in the register file entails two challenges: (i) the lifetime significantly decreases as data are frequently written into a register file; (ii) the delay of the critical path increases as a result of the slow write operation. They have proposed using two well‐known micro‐architectural approaches: the last‐write‐update (LWU) and the value locality (VL), to minimize the number of write operations into a register. The main observation behind LWU is that only the last write operations of certain registers in the re‐order buffer should be considered. VL exploits the fact that a limited number of values are more likely to be written into a register file. Their simulation shows that by employing the LWU and VL approaches, the lifetime of the STTRAM‐based register file, compared with the lifetime of traditional static RAM‐based register file architecture, extends to about 40 years on average and around 3.5 years in the worst case while improving power consumption by 30%. [ABSTRACT FROM AUTHOR]

Long timescales and complex design processes require that CPU architects and microarchitects have early access to information about future manufacturing processes. In some cases, this means that future technology must be predicted in advance of it actually being developed. In addition, close collaboration with the foundries, known as 'Design‐Technology Co‐Optimisation', or DTCO, allows the mutual influence during development of microarchitecture, physical IP (standard cells and memories), and process technology. This predictive technology, in conjunction with early technology information or not, allow design exploration in the form of trial runs of synthesis, place and route to determine the predicted effects of various technology choices on CPU power, performance, and area. [ABSTRACT FROM AUTHOR]

Background: Glucocorticoid-induced osteoporosis (GIO) is the most common secondary form of osteoporosis, and glucocorticoid users are at increased risk for fracture compared with nonusers. There is no established relationship between bone mineral density (BMD) and fracture risk in GIO. We used 3 Tesla (T) MRI to investigate how proximal femur microarchitecture is altered in subjects with GIO.Methods: This study had institutional review board approval. We recruited 6 subjects with long-term (> 1 year) glucocorticoid use (median age = 52.5 (39.2-58.7) years) and 6 controls (median age = 65.5 [62-75.5] years). For the nondominant hip, all subjects underwent dual-energy x-ray absorptiometry (DXA) to assess BMD and 3T magnetic resonance imaging (MRI, 3D FLASH) to assess metrics of bone microarchitecture and strength.Results: Compared with controls, glucocorticoid users demonstrated lower femoral neck trabecular number (-50.3%, 1.12 [0.84-1.54] mm(-1) versus 2.27 [1.88-2.73] mm(-1) , P = 0.02), plate-to-rod ratio (-20.1%, 1.48 [1.39-1.71] versus 1.86 [1.76-2.20], P = 0.03), and elastic modulus (-64.8% to -74.8%, 1.54 [1.22-3.19] GPa to 2.31 [1.87-4.44] GPa versus 6.15 [5.00-7.09] GPa to 6.59 [5.58-7.31] GPa, P < 0.05), and higher femoral neck trabecular separation (+192%, 0.705 [0.462-1.00] mm versus 0.241 [0.194-0.327] mm, P = 0.02). There were no differences in femoral neck trabecular thickness (-2.7%, 0.193 [0.184-0.217] mm versus 0.199 [0.179-0.210] mm, P = 0.94) or femoral neck BMD T-scores (+20.7%, -2.1 [-2.8 to -1.4] versus -2.6 [-3.3 to -2.5], P = 0.24) between groups.Conclusion: The 3T MRI can potentially detect detrimental changes in proximal femur microarchitecture and strength in long-term glucocorticoid users. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the within-day and between-day measurement reproducibility of in vivo 3D MRI assessment of trabecular bone microarchitecture of the proximal femur.Materials and Methods: This Health Insurance Portability and Accountability Act (HIPPA)-compliant, Institutional Review Board (IRB)-approved study was conducted on 11 healthy subjects (mean age = 57.4 ± 14.1 years) with written informed consent. All subjects underwent a 3T MRI hip scan in vivo (0.234 × 0.234 × 1.5 mm) at three timepoints: baseline, second scan same day (intrascan), and third scan 1 week later (interscan). We applied digital topological analysis and volumetric topological analysis to compute the following microarchitectural parameters within the femoral neck: total bone volume, bone volume fraction, markers of trabecular number (skeleton density), connectivity (junctions), plate-like structure (surfaces), plate width, and trabecular thickness. Reproducibility was assessed using root-mean-square coefficient of variation (RMS-CV) and intraclass correlation coefficient (ICC).Results: The within-day RMS-CVs ranged from 2.3% to 7.8%, and the between-day RMS-CVs ranged from 4.0% to 7.3% across all parameters. The within-day ICCs ranged from 0.931 to 0.989, and the between-day ICCs ranged from 0.934 to 0.971 across all parameters.Conclusion: These results demonstrate high reproducibility for trabecular bone microarchitecture measures derived from 3T MR images of the proximal femur. The measurement reproducibility is within a range suitable for clinical cross-sectional and longitudinal studies in osteoporosis. [ABSTRACT FROM AUTHOR]

Purpose: Osteoporosis is a common bone disease associated with increased risk of low-trauma fractures leading to substantial morbidity, mortality, and financial costs. Clinically, osteoporosis is defined by low bone mineral density (BMD); however, increasing evidence suggests that trabecular bone (TB) microarchitectural quality is an important determinant of bone strength and fracture risk. A tensor scale based algorithm for in vivo characterization of TB plate-rod microarchitecture at the distal tibia using multirow detector CT (MD-CT) imaging is presented and its performance and applications are examined. Methods: The tensor scale characterizes individual TB on the continuum between a perfect plate and a perfect rod and computes their orientation using optimal ellipsoidal representation of local structures. The accuracy of the method was evaluated using computer-generated phantom images at a resolution and signal-to-noise ratio achievable in vivo. The robustness of the method was examined in terms of stability across a wide range of voxel sizes, repeat scan reproducibility, and correlation between TB measures derived by imaging human ankle specimens under ex vivo and in vivo conditions. Finally, the application of the method was evaluated in pilot human studies involving healthy young-adult volunteers (age: 19 to 21 yr; 51 females and 46 males) and patients treated with selective serotonin reuptake inhibitors (SSRIs) (age: 19 to 21 yr; six males and six females). Results: An error of (3.2%±2.0%) (mean±SD), computed as deviation from known measures of TB plate-width, was observed for computer-generated phantoms. An intraclass correlation coefficient of 0.95 was observed for tensor scale TB measures in repeat MD-CT scans where the measures were averaged over a small volume of interest of 1.05 mm diameter with limited smoothing effects. The method was found to be highly stable at different voxel sizes with an error of (2.29%±1.56%) at an in vivo voxel size as compared to the original ex vivo voxel size. Tensor scale measures derived from imaging under in vivo and ex vivo conditions with significantly different modulation transfer function, i.e., difference in "true resolution," showed strong linear correlation (r = 0.92). The study of healthy volunteers shows that, after adjustment for height and weight, males have a 14% higher mean TB plate-width as compared to females (p < 0.05). SSRI-treated patients have 12.5% lower mean TB plate-width (p = 0.052) as compared to age-similar and sex-, height-, and weight-matched healthy controls. In contrast, the observed group difference in dual-energy x-ray absorptiometry (DXA)-derived hip BMD was 10.5% between males and females and only 5.04% between healthy controls and patients on SSRIs. Conclusions: Tensor scale analysis of MD-CT images yields accurate and reproducible characterization of TB plate-rod microarchitecture that may be more sensitive than DXA-derived BMD to sex differences and to the skeletal changes associated with medical conditions or their treatments. [ABSTRACT FROM AUTHOR]

ABSTRACT The studies of entheses in bioarchaeology attempted to reconstruct the habitual physical activities of past populations. However, the studies of microarchitecture of the underlying bone are still lacking despite well-known potential of bone internal microarchitecture to reflect mechanical loading. It is unknown whether different morphological expressions of entheseal changes (ECs) correlate with the microstructural characteristics of the underlining bone. This study analyzed bone microstructural characteristics at the entheses. Our focus was on examining the possible successive nature of the three-stage scale of entheseal macroscopic changes by comparing EC scores with the microarchitectural features at the attachment sites. The study was based on the hypothesis that mechanical loading influences the microarchitecture of the bone at the attachment site. The bone samples were taken from 24 adult male skeletons from medieval cemeteries in Serbia, with different macroscopic expression score of EC. We evaluated the macroscopic and microscopic appearance of four entheses of the lower limbs (origin of the soleus muscle and the insertions of the adductor magnus, gluteus maximus, and iliopsoas muscles). The specimens were scanned using microcomputed tomography (Scanco µCT 40). Our data showed a lack of consistent correlation between stages of the macroscopic scoring systems with microarchitecture at the entheses, only cortical thickness was significantly different between EC stages. Analyzing relationship between trabecular and cortical bone microstructure we found correlations between cortical and trabecular variables only in Stage C. Results of our study suggest that macroscopic EC might not represent distinct successive phases in bone adaptation to mechanical loading. Am J Phys Anthropol 157:81-93, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Cylindrical critical size defects were created at the distal femoral condyles bilaterally of eight female adult sheep. Titanium implants with 2-mm concentric gaps were inserted and the gaps were filled with one of the four materials: allograft; a synthetic 15-amino acid cell-binding peptide coated hydroxyapatite (ABM/P-15); hydroxyapatite + βtricalciumphosphate+ Poly-Lactic-Acid (HA/βTCP-PDLLA); or ABM/P-15+HA/βTCP-PDLLA. After nine weeks, bone-implant blocks were harvested and sectioned for micro-CT scanning, push-out test, and histomorphometry. Significant bone formation and implant fixation could be observed in all four groups. Interestingly, the microarchitecture of the ABM/P-15 group was significantly different from the control group. Tissue volume fraction and thickness were significantly greater in the ABM/P-15 group than in the allograft group. Bone formation and bone ingrowth to porous titanium implant were not significantly different among the four groups. The ABM/P-15 group had similar shear mechanical properties on implant fixation as the allograft group. Adding HA/βTCP-PDLLA to ABM/P-15 did not significantly change these parameters. This study revealed that ABM/P-15 had significantly bone formation in concentric gap, and its enhancements on bone formation and implant fixation were at least as good as allograft. It is suggested that ABM/P-15 might be a good alternative biomaterial for bone implant fixation in this well-validated critical-size defect gap model in sheep. Nevertheless, future clinical researches should focus on prospective, randomized, controlled trials in order to fully elucidate whether ABM/P-15 could be a feasible candidate for bone substitute material in orthopedic practices. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1357-1365, 2015. [ABSTRACT FROM AUTHOR]

Coronary artery bypass grafting is one of the most commonly performed major surgeries in the United States. Autologous vessels such as the saphenous vein are the current gold standard for treatment; however, synthetic vascular prostheses made of expanded poly(tetrafluoroethylene) or poly(ethylene terephthalate) are used when autologous vessels are unavailable. These synthetic grafts have a high failure rate in small diameter (<4 mm) applications due to rapid reocclusion via intimal hyperplasia. Current strategies to improve clinical performance are focused on preventing intimal hyperplasia by fabricating grafts with compliance and burst pressure similar to native vessels. To this end, we have developed an electrospun vascular graft from segmented polyurethanes with tunable properties by altering material chemistry and graft microarchitecture. Relationships between polyurethane tensile properties and biomechanical properties were elucidated to select polymers with desirable properties. Graft thickness, fiber tortuosity, and fiber fusions were modulated to provide additional tools for controlling graft properties. Using a combination of these strategies, a vascular graft with compliance and burst pressure exceeding the saphenous vein autograft was fabricated (compliance = 6.0 ± 0.6%/mmHg × 10−4, burst pressure = 2260 ± 160 mmHg). This graft is hypothesized to reduce intimal hyperplasia associated with low compliance in synthetic grafts and improve long-term clinical success. Additionally, the fundamental relationships between electrospun mesh microarchitecture and mechanical properties identified in this work can be utilized in various biomedical applications. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 313-323, 2015. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis This investigation quantitatively characterizes the collagenous microstructure of human vocal ligament specimens excised postmortem from nonsmokers and smokers. Study Design Retrospective cohort study. Methods Second harmonic generation (SHG) imaging was performed at three anatomical locations of vocal ligament specimens: anterior, mid-membranous, and posterior regions. Two microstructural parameters were extracted from the SHG images: (1) normalized fiber density, and (2) fiber dispersion coefficient, quantifying the degree of collagen fiber dispersion about a preferred direction. Results For both the nonsmoker and smoker subjects, the fiber dispersion coefficient was heterogeneous. Differences in the collagenous structure of nonsmokers and smoker subjects were pronounced at the mid-membranous location. However, the directionality of the heterogeneity in the smoker subjects was opposite to that in the nonsmoker subjects. Specifically, the fiber dispersion coefficient in the nonsmoker subjects was lower in the mid-membranous region (indicating more fiber alignment) than at the anterior/posterior regions, but for the smoker subjects the fiber dispersion coefficient was higher at the mid-membranous region. The normalized fiber density was near constant in the nonsmoker subjects, but the smoker subjects had fewer fibers in the mid-membranous region than at the anterior/posterior regions. Conclusion Spatial microstructural variations may exist in the vocal fold ligament both in nonsmokers and smokers. Smoking appears to influence the degree and direction of microstructure heterogeneity in the vocal fold ligament. Level of Evidence N/A. Laryngoscope, 124:E361-E367, 2014 [ABSTRACT FROM AUTHOR]

Objective Cone-beam CT ( CBCT) images are infrequently utilized for trabecular bone microstructural measurement due to the system's limited resolution. The aim of this study was to determine the accuracy of CBCT for measuring trabecular bone microstructure in comparison with micro CT (μ CT). Materials and methods Twenty-four human mandibular cadavers were scanned using a CBCT system (80 μm) and a μ CT system (35 μm). Three bone microstructural parameters trabecular number (Tb.N), thickness (Tb.Th) and separation (Tb.Sp) were assessed using CTAn imaging software. Results Intraclass correlation coefficients ( ICC) showed a high intra-observer reliability (≥ 0.996) in all parameters for both systems. The Pearson correlation coefficients between the measurements of the two systems were for Tb.Th 0.82, for Tb.Sp 0.94 and for Tb.N 0.85 (all P's<0.001). The Bland and Altman plots showed strongest agreement in Tb.N (-0.37 μm) followed by Tb.Th (1.6μm) and Tb.Sp (8.8μm). Conclusions Cone-beam CT datasets can be used to evaluate trabecular bone microstructure at dental implant sites. The accuracy for measuring Tb.N was the best followed by Tb.Th and Tb.Sp. [ABSTRACT FROM AUTHOR]

ABSTRACT Bone quality, a contributor to bone strength, is determined by structural and mechanical properties, which may be analyzed by gross and/or microscopic methods. Variables that contribute to bone quality, such as porosity, can provide insight into the health and lifestyles of people in prehistory. This study tests the ability of microcomputed tomography (µCT) to capture and characterize cortical canal systems in archaeological bone. Seven variables and 71 femora are analyzed to explore bone dynamics in prehistoric foragers from Lake Baikal, Siberia. The results indicate that canal number and canal separation differ significantly ( P < 0.05) between age-at-death categories, but only for the pooled and male samples. When merged into a new variable by means of principal components analysis, canal diameter and canal surface to canal volume are also able to discriminate amongst age-at-death categories, as well as between the sexes. However, the overall lack of significant differences between the sexes and amongst age-at-death categories indicates that Baikal forager bone quality (i.e., canal architecture) did not change drastically throughout the lifespan. Interestingly, principal component one identified an untested variable that contributes to canal microstructure variability, and a sexual division of labor may promote divergent trends in canal degree of anisotropy between the sexes. Overall, µCT provides an alternate method for exploring bone quality in archaeological remains, complementing existing methods such as thin-sectioning and gross morphological analyses. Am J Phys Anthropol 154:486-497, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective It is said to be difficult to interpret the different endometrial lesions by cytomorphology; however, evaluation of the microarchitecture of the cell clumps and application of immunocytochemistry can improve diagnostic accuracy. The aim of the present study was to evaluate cytolomorphological features and correlate them with the histological diagnosis of benign and malignant endometrial lesions, and to investigate certain immunocytochemical biomarkers to achieve a more accurate cytodiagnosis. Methods In the present study, we graded the cytomorphology on imprint smears of 35 low-grade endometrial endometrioid carcinomas compared with 23 cases of endometrium ranging from disordered proliferative to benign hyperplastic. Additionally, 10 cases of high-grade endometrial carcinoma and 11 cases of atrophic endometrium were evaluated. Ki-67 and p53 biomarkers were applied to the cytological smears. Results A total cytological score less than six, resulting from nuclear overlapping, nuclear/cytoplasmic ratio, the presence of a branched pattern, vesicular cytoplasm and loss of cohesiveness, distinguished all the cases of disordered proliferative and benign hyperplastic endometrium from low-grade endometrioid carcinomas of endometrium ( P < 0.0001). The application of different cut-off values for Ki-67 and p53 helped differentiate certain endometrial lesions in our study. The integration of the immunocytochemical score of Ki-67 and p53 into the cytological score resulted in a final score that was also diagnostically useful. Conclusions The results of the present study demonstrated that evaluation of certain cytological features along with specific immunocytochemical findings could improve the accuracy of endometrial cytodiagnosis but our findings need to be tested in a routine clinical situation, using pre-operative cytological samples, to ascertain whether the diagnostic criteria are reproducible. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy ( DMD) is a common inherited muscle disease showing chronic inflammation and progressive muscle weakness. Absent dystrophin renders sarcolemma more Ca2+-permeable, disturbs signalling and triggers inflammation. Sustained degeneration/regeneration cycles render muscle cytoarchitecture susceptible to remodelling. Quantitative morphometry was introduced in living cells using second-harmonic generation ( SHG) microscopy of myosin. As the time course of cellular remodelling is not known, we used SHG microscopy in mdx muscle fibres over a wide age range for three-dimensional ( 3D) rendering and detection of verniers and cosine angle sums ( CASs). Wild-type (wt) and transgenic mini-dystrophin mice ( MinD) were also studied. Vernier densities ( VDs) declined in wt and MinD fibres until adulthood, while in mdx fibres, VDs remained significantly elevated during the life span. CAS values were close to unity in adult wt and MinD fibres, in agreement with tight regular myofibril orientation, while always smaller in mdx fibres. Using SHG 3D morphometry, we identified two types of altered ultrastructure: branched fibres and a novel, previously undetected 'chaotic' fibre type, both of which can be classified by distinct CAS and VD combinations. We present a novel model of tissue remodelling in dystrophic progression with age that involves the transition from normal to chaotic to branched fibres. Our model predicts a ∼50% contribution of altered cytoarchitecture to progressive force loss with age. We also provide an improved automated image algorithm that is suitable for future ageing studies in human myopathies. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Previous studies have shown that the mechanical properties of trabecular bone are determined by bone volume fraction (BV/TV) and microarchitecture. The purpose of this study was to explore other possible determinants of the mechanical properties of vertebral trabecular bone, namely collagen cross-link content, microdamage, and mineralization. Trabecular bone cores were collected from human L2 vertebrae ( n = 49) from recently deceased donors 54-95 years of age (21 men and 27 women). Two trabecular cores were obtained from each vertebra, one for preexisting microdamage and mineralization measurements, and one for BV/TV and quasi-static compression tests. Collagen cross-link content (PYD, DPD, and PEN) was measured on surrounding trabecular bone. Advancing age was associated with impaired mechanical properties, and with increased microdamage, even after adjustment by BV/TV. BV/TV was the strongest determinant of elastic modulus and ultimate strength ( r = 0.44 and 0.55, respectively). Microdamage, mineralization parameters, and collagen cross-link content were not associated with mechanical properties. These data indicate that the compressive strength of human vertebral trabecular bone is primarily determined by the amount of trabecular bone, and notably unaffected by normal variation in other factors, such as cross-link profile, microdamage and mineralization. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:481-488, 2011 [ABSTRACT FROM AUTHOR]

The goal of this study was to examine the microarchitecture of the trabecular bone of the canine femoral head using microcomputed tomography (micro-CT) technology. Specifically, we assessed changes seen in the femoral head in dogs with Legg-Calvé-Perthes disease and compared this with changes seen in dogs with hip dysplasia and coxofemoral luxation. Femoral heads from healthy animals were examined as a control. In total, 38 femoral heads were studied. Rules for defining spherical volumes (region of interest) for determination of the structural parameters within the trabecular structure were established using micro-CT images. The following parameters were determined directly in three dimensions: bone volume fraction, surface volume fraction, trabecula thickness, trabecular count, trabecular spacing, and connectivity. Characteristic femoral head changes were found for each condition. An unexpected result was found that contradicts the prevailing understanding of Legg-Calvé-Perthes disease. Instead of observing a thickening of the bone trabeculae caused by layering of new bone matrix on top of necrotic trabeculae, we observed an increase in trabecular count and a smaller trabecular thickness. From this it may be concluded that trabecular regeneration is more prominent or prevails over the characteristically described layering processes in the revascularization and repair processes occurring in this illness. [ABSTRACT FROM AUTHOR]

The lumbar vertebrae are major load-bearing structures within the spinal column. The current understanding of the microstructure of these bodies and their full role in load-bearing is incomplete. There is a need to develop our understanding of these issues to improve fracture prediction in musculoskeletal diseases such as osteoporosis. The lumbar vertebrae consist primarily of trabecular bone enclosed in a thin cortical shell, but little is known about how microstructural parameters vary within these structures, particularly in relation to the trabecular compartment. The specific aim of this study was to use micro-computed tomography to characterize the trabecular microarchitecture of the ovine L3 vertebra in cranial, mid-vertebra and caudal regions. The L3 vertebra was obtained from skeletally mature ewes ( n = 18) more than 4 years old. Three-dimensional reconstructions of three pre-defined regions were obtained and microarchitectural parameters were calculated. Whereas there was no difference in bone volume fraction or structural model index between regions, trabecular number, thickness, spacing, connectivity density, degree of anisotropy and bone mineral density all displayed significant regional variations. The observed differences were consistent with the biomechanical hypothesis that in vivo loads are distributed differently at the endplates compared with the mid-vertebra. Thus, a more integrative approach combining biomechanical theory and anatomical features may improve fracture risk assessment in the future. [ABSTRACT FROM AUTHOR]

Although adult skeletal morphological variation is best understood within the framework of age-related processes, relatively little research has been directed towards the structure of and variation in trabecular bone during ontogeny. We report here new quantitative and structural data on trabecular bone microarchitecture in the proximal tibia during growth and development, as demonstrated in a subadult archaeological skeletal sample from the Late Prehistoric Ohio Valley. These data characterize the temporal sequence and variation in trabecular bone structure and structural parameters during ontogeny as related to the acquisition of normal functional activities and changing body mass. The skeletal sample from the Fort Ancient Period site of SunWatch Village is composed of 33 subadult and three young adult proximal tibiae. Non-destructive microCT scanning of the proximal metaphyseal and epiphyseal tibia captures the microarchitectural trabecular structure, allowing quantitative structural analyses measuring bone volume fraction, degree of anisotropy, trabecular thickness, and trabecular number. The microCT resolution effects on structural parameters were analyzed. Bone volume fraction and degree of anisotropy are highest at birth, decreasing to low values at 1 year of age, and then gradually increasing to the adult range around 6-8 years of age. Trabecular number is highest at birth and lowest at skeletal maturity; trabecular thickness is lowest at birth and highest at skeletal maturity. The results of this study highlight the dynamic sequential relationships between growth/development, general functional activities, and trabecular distribution and architecture, providing a reference for comparative studies. [ABSTRACT FROM AUTHOR]

The mechanical behavior of bone is a critical factor in the attainment and maintenance of osseointegration. Current procedures and classifications in assessing bone quality have limitations. Micro-computed tomography (microCT) is a new method to image and quantify bone with very high resolution. This study was aimed to analyze cadaveric maxillary and mandibular trabecular bone with 3-D morphometric data acquired through microCT and correlate with conventional bone assessment methods. Moderately resorbed edentulous maxilla and mandible from a human cadaver were scanned in the conventional CT unit with opaque markers indicating specific anterior and posterior sites. These sites were then sectioned and standard periapical radiographs were obtained. Bone cores were harvested from the sectioned sites and scanned in the microCT unit. Bone density values based on the Hounsfield scale ranged from 51 to 529 in the mandible and 186 to 389 in the maxilla, anterior sites being higher in both. Periapical images did not yield distinct differences. 3-D morphometric analysis in microCT produced a range of values with anterior specimens being favorable: bone volume density (0.12–0.291), trabecular thickness (0.12–0.16 mm), trabecular separation (0.46–0.82 mm), trabecular number (1.08–2.071/mm) and structural model index (0.29–1.27). General agreement between bone density and microCT indices was noted; however, subtle differences have to be studied with larger samples. This preliminary study suggests that the understanding of mechanical competence of trabecular bone might reveal further information about the prognosis of implant therapy, advancements in implant design, surgical techniques and grafting. To cite this article: Fanuscu MI, Chang T-L. Three-dimensional morphometric analysis of human cadaver bone: microstructural data from maxilla and mandible. Clin. Oral Impl. Res. [ABSTRACT FROM AUTHOR]