Search Results (945)

The present study was conducted to investigate the effect of dietary supplementation with the probiotic Zoovit LL—alone or in combination with a phytogenic blend—on bone morphometry and mineral concentrations in broilers by computed tomography (CT) and ICP-MS analysis. A total of 180 one-day-old male ROSS 308 chicks were randomly assigned to three groups with three replicates of 20 chicks each: control (standard diet), Zoovit LL (0.25%) and Zoovit LL (0.25%) in combination with Silybum marianum, Urtica dioica and Taraxacum officinale in a total amount of 1%. After 42 days, two birds were averaged within each replicate, resulting in three independent experimental units per treatment (n = 3 per group). Femurs were examined by CT for bone length, cortical bone thickness, diameters and radiodensity, while determination of calcium, phosphorus and magnesium concentrations in the sternum was performed by ICP-MS. No statistically significant effects of the nutritional supplements were found on the bone parameters assessed by computed tomography or on the mineral concentrations in the sternum. The results show that under the conditions of the present study, the addition of the probiotic alone or in combination with the phytogenic mixture did not lead to statistically significant changes in the specific parameters studied. Full article

Purpose: Excessive drill advancement after cortical breakthrough is a potential safety concern in orthopaedic procedures. We developed a data-driven approach to estimate the drill-tip position relative to the far cortex prior to breakthrough using time-series thrust force and spindle torque signals. Methods: Drilling experiments were performed on 268 porcine cortical bone specimens at a constant feed rate of 0.5 mm/s. A long short-term memory network was trained to estimate the drill-tip position from filtered force and torque signals. The reference position was derived from breakthrough timing confirmed by high-speed imaging and the programmed feed rate. Performance was evaluated using mean absolute error within the −2 to +2 mm peri-breakthrough interval. Two post hoc analyses examined whether model performance exceeded an elapsed-time baseline and whether pre-breakthrough force patterns were more consistent when expressed relative to breakthrough position than to drilling onset time. Results: The combined-input LSTM achieved an MAE of 0.20 mm, compared with 0.23 mm for force alone and 0.24 mm for torque alone. Among the representative architectures evaluated, LSTM showed the lowest regression error. A signal-blind time-only baseline yielded an MAE of 0.54 mm. The association between cortical thickness and force-decline onset was weaker when expressed in spatial coordinates relative to breakthrough than when expressed as time from drilling onset (R² = 23% vs. 74%). These findings suggest that force and torque signals contained information associated with proximity to breakthrough beyond that provided by average drilling duration alone. Conclusion: Converting sensor-derived resistance patterns into spatially anchored positional information may support proactive strategies such as controlled deceleration before penetration. The proposed approach represents a step toward exemplifying the emerging concept of surgeon-assisting Physical AI. Full article

Chitosan and calcium phosphate (CaP) are attractive bioactive coating materials for titanium (Ti) orthopedic implants, but coating approaches must provide uniform deposition, adequate adhesion, and cytocompatibility. This proof-of-concept study evaluated whether CaP microshells could be incorporated into electrosprayed chitosan coatings bonded to silanized Ti substrates without compromising coating properties. CaP microshells were synthesized using carbon microsphere templates and added to chitosan electrospray solutions at 0.25, 0.5, and 1.0 wt% relative to chitosan. Electrospray parameters were adjusted, and coatings were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, tensile adhesion testing, water contact angle measurements, and W-20-17 bone marrow stromal cell culture. Increasing capillary diameter and reducing pressure enabled stable deposition of uniform composite coatings containing up to 1.0 wt% CaP. CaP microshells were distributed across the coating surfaces and throughout the coating thickness. Silanization significantly increased coating adhesion compared with non-silanized Ti, while CaP incorporation up to 1.0 wt% did not significantly reduce bond strength. All coatings were hydrophilic and supported viable cell attachment and growth over five days. These findings support the feasibility of electrosprayed chitosan–CaP microshell coatings as adhesive, cytocompatible bioactive coating platforms for Ti implant materials. Full article

Ti–Nb alloys are widely recognized as highly promising materials for orthodontic applications due to their excellent functional properties, including superior biocompatibility and a relatively low Young’s modulus that better matches that of human bone. The formation of Ti–Nb surface alloys or surface-modified layers is particularly attractive, as the surface properties of biomedical materials strongly influence their mechanical and biological interactions during service. In the present study, Ti-Nb coatings were fabricated on commercially pure titanium substrates using an electron beam surface treatment (EBST) technique. Initially, a 1 μm thick Nb layer was deposited onto the Ti substrates by direct current (DC) magnetron sputtering. Subsequently, the samples were modified through scanning electron beam irradiation, with beam power varied between 1000 and 2000 W to promote Ti-Nb alloyed layers. The phase composition of the resulting structures was analyzed by X-ray diffraction (XRD). Microstructural characteristics and chemical composition were examined using scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Mechanical properties were evaluated in terms of hardness and Young’s modulus. The findings of this study demonstrate the feasibility of tailoring the structural and mechanical properties of Ti–Nb surface alloys through controlled electron-beam processing and support their further investigation for potential orthodontic and dental applications. Full article

Background: The contribution of specific nutritional biomarkers to skeletal fragility remains poorly understood, in part because most studies include participants with metabolic conditions that obscure nutrient-specific effects. We aimed to examine incremental contribution of six pathway-specific nutritional biomarkers. Methods: In a prospective cross-sectional case–control design, 108 patients undergoing arthroplasty were enrolled (hip-fracture, n = 63; non-fracture, n = 45), and bone biopsies and blood specimens were collected intraoperatively. Circulating biomarkers reflecting vitamin K, one-carbon metabolism, antioxidant nutrients (vitamins E and C), protein and zinc status were measured. Bone outcomes included remodelling markers, trabecular microarchitecture and bone strength. Hierarchical regression was used to quantify the incremental contribution of nutritional biomarkers beyond clinical covariates with a priori outcome selection. Results: Bone remodelling markers did not differ between groups after covariate adjustment, indicating that fractures in this cohort were characterised by deficits in bone strength and quality rather than elevated systemic remodelling activity. Among six nutritional pathways tested, only vitamin K-dependent biomarkers showed consistent independent associations with bone outcomes, suggesting a degree of pathway specificity. Critically, carboxylated (cOC), undercarboxylated (ucOC) and fully uncarboxylated (unOC) osteocalcin fractions showed differential associations reflecting their distinct biological roles: cOC was independently associated with greater bone strength (section modulus, femoral neck width and cortical shaft thickness; p < 0.05) and lower trabecular separation (Tb.Sp); ucOC was associated with higher Tb.Sp (p = 0.004); and unOC was positively associated with cortical bone instability (buckling ratio, p = 0.003) and explained 17% of the variance in the bone resorption marker (p < 0.001), consistent with a shift towards bone loss. Vitamin K2-7 was negatively associated with hip axis length (p = 0.021). Conclusions: These findings identify vitamin K-dependent carboxylation as a mechanistically specific and modifiable factor associated with skeletal fragility beyond bone mineral density, with distinct skeletal consequences across osteocalcin carboxylation states. Full article

Background/Objectives: Solid bone cement is a poor vehicle for delivering antibiotics, and porous bone cement lacks mechanical robustness. Inspired by the different structural phases of bone, we hypothesized that porous shell cements (PSCs) could be synthesized to be both mechanically resilient and effective in eluting antibiotics. Our objective was to synthesize and characterize PSCs and compare their physicochemical properties to solid and porous cements. Methods: PSCs were synthesized with thin versus thick outer porous shells and compared to homogenous solid and porous cements as controls. Porosity and architecture were assessed through scanning electron microscopy and microcomputed tomography. Mechanical properties were quantified by compression testing. Antibiotic release kinetics and antibiotic activity were measured via release assays, disc diffusion assays, and minimum inhibitory concentration tests. Results: PSCs exhibit both solid and porous regions within a single bone cement construct with enhanced surface area to volume ratios in porous regions. Cements with porous regions have lower synthesis heat during polymerization. The mechanical strength of PSCs correlates with the ratio of solid core to porous shell thickness. The addition of the porous shell layer significantly increases antibiotic elution and increases the inhibition of Staphylococcus aureus and Staphylococcus epidermidis strains. Conclusions: We are able to synthesize customizable PSCs that balance the mechanical strength of solid bone cement with the antibiotic release profile of porous cement as a new biomaterial strategy to prevent orthopaedic device infection. Full article

Perirenal adipose tissue (PRAT) has emerged as a clinically relevant endocrine organ connecting obesity to cardiovascular disease (CVD), chronic kidney disease, and certain malignancies. Its unique anatomical location, surrounding the kidneys, accounts for PRAT’s role in altering intrarenal haemodynamics and hydrostatic pressure. Accordingly, PRAT’s expansion is associated with the activation of the renin–angiotensin–aldosterone system (RAAS), further increasing blood pressure. Adipokine dysregulation, together with overexpression of miR-24-3p, miR-155, miR-146a, and miR-21 in PRAT, modulates inflammation and oxidative stress, leading to endothelial dysfunction and increased risk of atherosclerosis and hypertension in obesity. Imaging assessment of PRAT thickness through computed tomography, magnetic resonance, or ultrasound has also emerged as a complementary measure for the evaluation of CVD risk. Potential therapeutic strategies targeting PRAT include lifestyle interventions, antidiabetic agents, RAAS inhibitors, adipose tissue browning agents, NOD-like receptor protein 3 (NLRP3) inflammasome inhibitors, peroxisome proliferator-activated receptor gamma (PPARγ) agonists, and surgery. Currently, novel therapeutic interventions targeting PRAT activity in CVD, such as senotherapeutic strategies, bioengineering approaches aimed at enhancing adipose-derived mesenchymal stem cell (ADMSC) function, gut microbiota modulation, and colchicine and bone morphogenetic protein 4 (BMP4) administration, are also being explored. In light of these findings, PRAT’s clinical relevance extends beyond its energy storage role, highlighting it as a metabolically active fat depot. Its assessment and therapeutic modulation may complement existing cardiovascular prevention strategies, particularly in patients with obesity. Full article

Extra-articular distal humerus fractures present surgical challenges, often requiring technically demanding posterior approaches with high radial nerve injury risks or off-label use of anatomically mismatched proximal plates. This study aimed to computationally design and optimize a novel anterior osteosynthesis plate for these fractures. A three-dimensional fracture model was developed, utilizing a parametric design exploration and finite element analysis to evaluate fourteen plate geometries. Evaluated variables included length, thickness, screw configuration, and locking mechanisms under physiological axial compression, bending, and varus loads. The analysis revealed that plate thickness primarily determines construct stability, with a four-millimeter profile optimally balancing rigidity and a low anatomical footprint. Lengths exceeding 40 mm yielded diminishing stability returns, while a dense distal locking screw configuration proved essential for maintaining fracture reduction. Compared to conventional clinical systems, the optimized plate substantially reduced the severe axial instability observed in extra-articular distal humerus plates and mitigated the critical bending stress concentrations inherent to proximal humeral internal locking systems. By achieving balanced, multi-planar stability with a minimized footprint, this novel design provides a favorable mechanical environment for secondary bone healing while facilitating a less invasive surgical approach. Full article

Background: Maxillary transverse deficiency is a common skeletal discrepancy in orthodontic patients that often requires expansion therapy for correction. Failure to address this condition during growth may compromise the orthopedic prognosis, frequently necessitating surgically assisted rapid palatal expansion (SARPE) or other orthognathic surgical procedures after skeletal maturity. Methods: The studies in this systematic review were selected according to predefined inclusion criteria. Randomized controlled trials, controlled clinical studies, and cohort studies published within the last 10 years with a follow-up ≥ 6 months were included. The databases PubMed, Scopus, and Embase were searched. Orthodontic outcomes included midpalatal suture opening, skeletal transverse changes, intermolar width variations, dental tipping, and long-term stability. Thirteen studies met the eligibility criteria. Risk of bias was assessed using the RoB 2 and the Newcastle–Ottawa Scale. Results: All orthodontic devices produced significant transverse expansion in the short term. Bone-borne and hybrid systems showed a greater initial skeletal component, with greater expansion at the maxillary and nasal basal levels and limited relapse over time. Tooth-borne expansion was associated with greater dental tipping and reduction in buccal bone thickness, with partial recovery during retention. Over time, loss of expansion mainly affected the dentoalveolar component, whereas the skeletal component remained more stable. Long-term data (≥3–5 years) remain limited but suggest that relapse is predominantly related to dental uprighting rather than a true loss of skeletal base width. Conclusions: Long-term transverse stability improves when expansion is predominantly skeletal. Bone-supported and hybrid appliances may produce a greater initial skeletal contribution and reduce dental tipping in some clinical settings; however, current evidence does not demonstrate superior long-term stability compared with tooth-borne expansion. Additional prospective orthodontic studies with extended follow-up, particularly without prolonged retention, are required. Full article

Type 1 diabetes mellitus (DM1) is characterized by autoimmune destruction of pancreatic β-cells, resulting in insulin deficiency and persistent hyperglycemia, which impair bone metabolism and compromise post-extraction alveolar bone healing. Heterologous fibrin biopolymer (HFB) has previously demonstrated biocompatibility, biodegradability, bioactivity, and osteoconductive properties under normoglycemic conditions. Therefore, the study investigated the association of HFB with post-extraction alveolar bone healing in streptozotocin-induced diabetic rats, using the diabetic blood clot as a biological control. Forty-eight adult male Wistar rats were induced to DM1 by a single intraperitoneal injection of streptozotocin (52 mg/kg). Animals were included after confirmation of hyperglycemia (fasting blood glucose ≥ 250 mg/dL) measured seven days after STZ administration: blood clot (BCG; n = 24) or HFB (HFBG; n = 24). Seven days after DM1 induction, the right maxillary incisor was extracted, and the sockets were filled according to group allocation. Animals were euthanized at 7, 14, and 42 days post-extraction. Fasting blood glucose levels were monitored, and pancreatic insulin immunohistochemistry was performed to characterize the diabetic condition. Alveolar bone healing was assessed by micro-CT, histological (HE), histomorphometric, and picrosirius red analyses. The diabetic phenotype was confirmed by persistent fasting hyperglycemia (260–589 mg/dL) and reduced pancreatic insulin immunostaining in β-cells. At 42 days, bone volume (BV) was 31.86% higher in the HFBG than in the BCG (p < 0.05). BCG exhibited higher trabecular number (Tb.N), while HFBG exhibited higher trabecular thickness (Tb.Th) (p < 0.05). Histologically, the HFBG shows a more mature, compact, and organized bone structure, whereas the BCG presents bone tissue with a more trabecular and immature architecture. HFBG showed the lowest percentage of thin fibers at the late stage, whereas BCG maintained similar values from 14 to 42 days (p < 0.05). These findings suggest that HFB was associated with favorable changes in selected late-stage parameters of post-extraction alveolar bone healing in an STZ-induced diabetic model. Full article

With the increasing use of diagnostic X-ray examinations and interventional procedures in medical institutions, the development of lead-free flexible X-ray shielding materials to reduce occupational exposure to scattered radiation has become increasingly important. Tungsten (W) is considered one of the most promising alternatives to lead (Pb) because of its high density and excellent attenuation characteristics. However, in highly filled composites, particle agglomeration and the formation of microvoids can reduce the effective density of the material, thereby limiting its shielding performance. In this study, calcined Ca–P inorganic powder derived from waste animal bone was applied as an auxiliary filler in W/PVC composite sheets to evaluate its potential for improving shielding performance through void reduction and effective density enhancement. Waste animal bone was calcined (600–1200 °C) to produce Ca–P powder. The calcined Ca–P was melt-compounded with tungsten/PVC and processed into 0.25 mm thick flexible shielding sheets. The fabricated sheets were characterized by cross-sectional scanning electron microscopy (SEM), bulk density measurements, and radiation protection efficiency (RPE) evaluations under effective X-ray energies ranging from 23.6 to 52.4 keV. SEM observations revealed a reduction in microvoids and the formation of a more continuous internal structure in the sheets containing calcined Ca–P. At the W-85 composition, the bulk density increased from 12.448 to 15.241 g/cm³, accompanied by an RPE improvement of up to 4.5 percentage points at 23.6 keV. Correspondingly, shielding performance improved by up to approximately 4.5 percentage points at 23.6 keV and by approximately 1.0–3.4 percentage points at 46.5 keV. These findings suggest that calcined Ca–P functions not as a primary shielding material replacing tungsten, but rather as a density-correcting auxiliary filler that mitigates microvoid formation and enhances the effective density of highly filled W/PVC composites. These findings demonstrate that waste animal bone-derived Ca–P is a promising upcycled densification filler for improving the processability and X-ray shielding performance of lead-free flexible shielding sheets. Full article

Background: Energy dissipation reflects the viscoelastic behavior of biological tissues and plays a key role in arterial elastic recoil and diastolic flow support. In the native aorta, efficient storage and release of mechanical energy are essential for maintaining ventriculo–aortic coupling. The energy dissipation ratio (EDR) quantifies the proportion of mechanical energy lost during a loading–unloading cycle and may provide insight into the biomechanical performance of aortic substitutes. Bovine pericardial patches (BPPs) are widely used in cardiovascular surgery for arterial reconstruction, patch angioplasty, and tubular replacement. Today, EDR has not been systematically investigated in BPPs. Methods: Forty glutaraldehyde-treated BPPs from four commercial manufacturers (n = 10 per supplier) were subjected to low-cycle fatigue testing using a uniaxial tensile system under controlled physiological conditions (37 °C). Standardized bone-shaped specimens were tested at progressive strain percentage levels. Thickness, EDR, and the percentage of specimens failing to reach progressively higher strain levels were evaluated from stress–strain hysteresis loops. Results: BPPs thickness ranged from 0.253 to 0.608 mm, with no significant differences among most groups. For the 10% strain, all BPPs reached the target deformation and demonstrated comparable EDR values. In detail, the mean EDR was 21.40 ± 7.02% for Edwards Lifesciences, 24.95 ± 6.80% for Supple Peri-Guard (Baxter), 24.99 ± 6.04% for Xenosure (LeMaitre), and 23.37 ± 6.12% for Invengenx–Tisgenx, with no statistically significant intergroup differences (p > 0.05). For the 20% strain, only 18.75% of specimens remained structurally intact, and variability increased. At 30% strain, structural failure occurred in nearly all samples. No significant orientation-dependent differences were observed. Conclusions: Commercially available BPPs exhibit similar biomechanical behavior under moderate deformation. However, tolerance to higher strain is limited. EDR analysis provides a clinically relevant parameter to assess elastic performance and may contribute to optimizing aortic substitute selection. Full article

Background: Palatal orthodontic mini-implants are increasingly used for sagittal, vertical, and transverse mechanics, including molar distalization, mesialization, posterior intrusion, impacted tooth traction, and miniscrew-assisted rapid palatal expansion. Yet site selection is often discussed as if anatomical bone availability were the dominant determinant of performance. Objective: This scoping review maps direct palatal evidence and supporting mechanistic evidence on how palatal substrate, miniscrew design, insertion protocol, digital planning, biomaterial surface, and biomechanical loading interact to determine primary stability, loaded stability, survival, and failure risk. Methods: Records were searched in PubMed/MEDLINE, Scopus and Web of Science Core Collection and organized into two evidence streams, as follows: P1 direct palatal evidence and P2 supporting mechanistic/biomaterials evidence. Data were charted using a Bone–Screw–Force framework. Results: The evidence indicates that anterior palatal and anterior paramedian sites are usually favorable for routine anchorage, but posterior sites, PPSAIS, and MARPE locations may warrant patient-specific three-dimensional assessment when clinical and conventional radiographic evaluation is insufficient. Primary stability emerges from cortical thickness, trabecular quality, effective intraosseous length, miniscrew diameter, thread design, insertion angle, pilot-hole protocol, torque, force magnitude, and biological response. Digital workflows are best interpreted as trajectory-control technologies rather than as convenience tools. Biomaterial and surface evidence remains promising but insufficiently connected to palatal-specific outcomes. Conclusions: Palatal miniscrew performance should be reframed as an interface problem rather than a site-only problem. A Bone–Screw–Force framework can support biomechanically driven site selection while identifying where quantitative evidence remains insufficient. Full article

Background/Objectives: In patients without clinically anticipated difficulty, an unexpected difficult airway carries the greatest potential for harm, yet routine bedside tests exclude difficulty poorly, and evidence for point-of-care ultrasonography remains heterogeneous, with difficult mask ventilation rarely studied as a distinct outcome. We evaluated three rapid anterior-neck ultrasonographic parameters—tongue thickness (TT), skin-to-hyoid-bone distance (SHBD), and cricothyroid membrane length (CTML)—for their diagnostic performance and independent association with a difficult airway in adults without anticipated difficulty. Methods: In this prospective, single-center, diagnostic-accuracy study reported per STARD 2015 and STROBE, 713 adults (ASA I–III) underwent neutral-position measurement of TT, SHBD, and CTML by a sonographer blinded to the clinical assessment and airway-management outcomes. A composite difficult airway (difficult mask ventilation, laryngoscopy, or intubation) was assessed independently. Discrimination was evaluated by ROC analysis with DeLong comparisons, multivariable logistic regression, and bootstrap internal validation; p-values used Benjamini–Hochberg correction. Results: A difficult airway occurred in 197/713 patients (27.6%). TT and SHBD were associated with the composite outcome and all components (AUC 0.68–0.73) and remained independent after adjustment for age, sex, BMI, and Mallampati class; CTML discriminated poorly (AUC ≈ 0.55), with only marginal significance after correction. Negative predictive values were high (78–99%) but prevalence-dependent, with modest likelihood ratios. Adding TT and SHBD to clinical variables improved discrimination (AUC 0.69 → 0.78; DeLong p < 0.001). Conclusions: TT and SHBD show a limited but independent diagnostic signal that may complement, not replace, clinical screening; CTML showed no clinically meaningful discrimination in this cohort. Proposed cut-offs are exploratory and require standardized measurement, reproducibility testing, and external validation before clinical adoption. Full article

Conventional push-out tests detect bone–implant failure only at the point of macroscopic instability, leaving earlier damage stages unresolved. Here we present a proof-of-concept for a push-out test stand combined with acoustic emission (AE) monitoring, aimed at capturing crack initiation before the macroscopic load drop. To provide a controlled failure process, samples were fabricated from SLA resin with defined breaking points, serving as mechanical surrogates rather than biological models. Four sample types with varying strut number and thickness were tested while recording AE, and post-processing was applied to remove friction and noise signals. A four-stage fracture model—initial, pre-fracture, fracture, and post-fracture—was defined, with the pre-fracture stage showing AE activity prior to any macroscopic load response. Increasing strut thickness and contact area raised maximum load resistance and AE activity, and Principal Component Analysis confirmed a progressive, intensity-driven separation of stages. The results demonstrate that AE monitoring resolves a pre-fracture regime inaccessible to conventional load measurement, establishing a methodological basis for future application to bone–implant samples. Full article