Aging and bone

Catharanthine tartrate ameliorates osteoclastogenesis by destabilizing HIF-1α

With the aging population, postmenopausal osteoporosis (PMOP), clinically manifested by reduced bone density, weakened skeletal strength, and compromised skeletal microstructure, has become the most prevalent type. The decline in estrogen levels fosters oxidative stress and osteoclastogenesis, which significantly enhance the activity of osteoclasts. Current treatments prefer to adopt relevant strategies to inactivate osteoclasts but come with unavoidable side effects. In our study, Catharanthine Tartrate (CAT), a derivative of the alkaloid catharanthine found in Catharanthus roseus, promised to be an effective therapy for PMOP. CAT inhibited RANKL-induced osteoclast differentiation and bone resorption in vitro. Moreover, CAT inhibited osteoclast activity by enhancing the ubiquitination-mediated proteasomal degradation of HIF-1α, which reduced oxidative stress and subsequently suppressed osteoclast activity. The inhibitory effects of CAT on osteoclast function and oxidative stress were reversed by DMOG, a known inhibitor of HIF-1α degradation. Next, an in vivo mouse experiment using the Ovariectomized (OVX) model to induce osteoporosis indicated that CAT enhanced bone mass density, bone structure, and bone remodeling. Our findings revealed that CAT inhibits PMOP through facilitating HIF-1α ubiquitination and degradation, suggesting a promising therapeutic approach for this disorder.

FKBP5 promotes osteogenic differentiation of mesenchymal stem cells through type-I interferon pathway Inhibition

The decreased osteogenesis of bone marrow mesenchymal stem cells (BMSCs) is an important factor causing bone loss. Nevertheless, its deep molecular mechanism has still not been fully clarified. To elucidate the regulatory mechanisms underlying BMSC osteogenesis, we conducted a bioinformatics screen using public datasets from the Gene Expression Omnibus (GEO) database to identify genes displaying significant expression dynamics during the osteogenic differentiation of BMSCs. We observed a significant upregulation of FK506 Binding Protein 5 (FKBP5) expression during the osteogenic differentiation of BMSCs. Besides, knockdown and overexpression of FKBP5 could reduce and increase osteogenic markers and Alizarin Red S (ARS) staining, respectively. Enrichment analysis of RNA sequencing (RNA-seq) demonstrated that downregulation of FKBP5 activated IFNα/β signaling pathway. FKBP5 overexpression relieved the inhibitory effect of IFNβ on osteogenesis. In addition, one of the upregulated interferon-stimulated genes (ISG), interferon-induced protein with tetratricopeptide repeats 2 (IFIT2), negatively regulated osteogenesis of BMSCs. IFIT2 knockdown rescued negative effect on osteogenesis caused by downregulation of FKBP5. Hydroxyapatite scaffold implanted in nude mice and drilled tibiae model in C57BL/6 mice confirmed positive role of FKBP5 in osteogenesis in vivo. Therefore, we determined the beneficial effect of FKBP5 on osteogenesis of BMSCs and validated the critical role of FKBP5/IFIT2 axis in this process. These findings might contribute to comprehension and treatment of bone diseases, like osteoporosis and bone fracture.

Increasing A-type CO32- substitution decreases the modulus of apatite nanocrystals

Biological apatite mineral is highly substituted with carbonate (CO32-). CO32- can exchange for either phosphate, known as B-type, or hydroxyl groups, known as A-type. Although the former has been extensively studied, A-type CO32- substituted apatites are poorly understood. Therefore, A-type CO32- apatites with biologically relevant levels of CO32- (1.7-5.8 wt%) were prepared and characterized. The addition of A-type CO32- into the apatite structure caused the predicted expansion of the a-axis and contraction of the c-axis in the unit cell. This was accompanied by a significant modification in the atomic order, especially along the a-axis plane, and crystallite size. A combination of in situ loading with synchrotron X-ray Diffraction and Density Functional Theory showed that increasing A-type CO32- substitutions also reduced the bulk and elastic moduli of the crystals. These results show that although A-type CO32- may inhibit lattice changes caused by B-type CO32-, A-type CO32- enhances the reduction in crystal order and mineral stiffness. These results help us to identify the possible contributions of A-type CO32- substitutions in biological apatites that contain both A- and B-type CO32-. In addition, this implies that the stiffness of bioapatite may change with increasing A-type CO32- substitutions, potentially altering the fracture mechanics of calcified tissues and biomaterials.

Evaluation of Invisalign Wear Protocol on the Efficacy of Tooth Movement in Four First-Premolar Extraction in Adolescent Patients: A Randomised Controlled Trial

BACKGROUND

Different protocols exist regarding wear time of invisible aligners. There is no study that compared the effect of different protocols. The aim of this study was to assess the effect of Invisalign aligners in four first-premolar extraction treatments in adolescents using three aligner wear protocols, every 7, 10 and 14 days.

MATERIALS AND METHODS

In the experimental set-up, 50 participants were divided into three distinct groups: group A, with a regimen of changing aligners every 7 days; group B, with a 10-day interval for aligner replacement; and group C, where aligners were replaced every 14 days. The evaluation of occlusal adjustments was conducted employing the Discrepancy Index (DI) and the Cast-Radiograph Evaluation (CRE), as defined by the American Board of Orthodontics for the purpose of recording orthodontic outcomes. The treatment duration, number of maxillary and mandibular Invisalign aligners, and number of Invisalign restarts were simultaneously recorded and evaluated. The data set was statistically examined using ANOVA, complemented by the F-test, least significant difference (LSD) method and Tamhane's T2 test.

RESULTS

The final sample size for analysis is 45 cases, with five cases lost to follow-up. Before treatment, the three groups showed no significant difference in the degree of malocclusion or each item of DI (p > 0.05). Posttreatment, within groups, and regardless of the wearing protocol, the total CRE scores demonstrated no statistically significant differences (p > 0.05). For the other items, groups A and C completed occlusal relations and interproximal contacts significantly better than did group B (p < 0.05). The group C cases had the least number of Invisalign refinement (3.93 ± 0.96 vs. 4.93 ± 0.70 vs. 6.00 ± 1.25, p < 0.05), but the treatment duration and number of Invisalign aligners were not significantly different (p > 0.05).

CONCLUSIONS

The different treatment timing protocols showed equivalent effectiveness regarding treatment outcome, with significantly improved results for the 7- and 14-day protocol in terms of occlusal relations and interproximal contacts. The attainment of comparable clinical accuracy between the 7- and 14-day protocol, within a treatment duration of fewer than 3 months, indicates that the 7-day protocol can be deemed an effective treatment approach.

Influence of the magnitude and orientation of forces on the odontoid fracture: A finite element model analyses

BACKGROUND

Fractures of the odontoid, prevalent among the elderly but affecting diverse demographics, pose significant risks ranging from mild discomfort to severe disability or fatality. These fractures, often stemming from trauma, are particularly frequent in the cervical spine. While commonly attributed to high-impact events like traffic accidents in adults, even low-energy incidents such as falls can precipitate these fractures in the elderly. Previous studies have explored loading conditions and treatment effects; however, a comprehensive investigation into the influence of the magnitude and direction of the force involved in the trauma, and the influence of the sex and age of the patient remains scarce so we want to delve deeper into this topic.

METHODS

This study uses a finite element (FE) model to analyze the response of 3D models of the second cervical vertebra (extracted from computed tomography images) exposed to different loads of magnitude and force. 52 patients were analyzed in this study. The patients were divided into 4 groups: male <70, female <70, male >70, female >70) under different force conditions. Von Mises stress values were obtained when loads of 200 N and 1500 N were applied to the anterior surface of the odontoid with different angles of incidence in the sagittal and axial plane.

RESULTS

Odontoid fractures in subjects over 70 years of age are more frequent in female, the maximum stresses produced in the odontoid are 181 MPa and are considerably higher compared to male, which is 131 MPa. In young subjects (<70 years), the differences between sex are less marked, 113 MPa for female and 114 MPa for male.

CONCLUSIONS

Load direction is one of the main factors affecting odontoid fracture, especially in subjects >70 years of age; by understanding this, the mechanisms that cause different types of fractures can be understood and better strategies can be proposed to apply different treatment approaches to them, both from a medical and surgical point of view.

Role of Canonical and Non-Canonical Sphingolipids and their Metabolic Enzymes in Bone Health

PURPOSE OF REVIEW

This review summarizes the recently published scientific evidence regarding the role of enzymes engaged in de novo anabolic biosynthesis, catabolic, and salvage pathways of ceramide bioactive sphingolipids in bone dynamics and skeletal health.

RECENT FINDINGS

Ceramides are precursors for bioactive sphingolipids, including sphingosine, sphingosine-1-phosphate, and others. Studies of bone metabolism and bone-related cells demonstrated that ceramide and sphingosine-1-phosphate control levels of bone remodeling and resorption generated by osteoblasts and osteoclasts. Multiple published studies demonstrated the critical role of enzymes in regulating the ceramide/sphingosine-1-phosphate ratio relative to bone physiology and the promotion of inflammatory osteolysis. Accordingly, emerging evidence suggests that targeting sphingolipid metabolism has the potential to alleviate inflammatory osteolysis and accelerate bone regeneration. Therefore, this study aimed to discuss current knowledge about crosstalk between sphingolipids and their metabolic enzymes within osteoclast and osteoblast coupling in bone remodeling and pathogenic osteolysis. This review highlights the complexity of de novo sphingolipid biosynthesis and knowledge gaps in bone physiology and pathology. We also discuss the importance of canonical and non-canonical mammalian and bacterial-derived sphingolipids relative to bone health.

Increasing Use of Cemented Stems Is Associated With Reduced Early Fracture After Total Hip Arthroplasty: A Michigan Arthroplasty Registry Collaborative Quality Initiative Study

BACKGROUND

The Michigan Arthroplasty Registry Quality Collaborative Initiative (MARCQI) identified periprosthetic fracture as the most common reason for early total hip arthroplasty (THA) revision of uncemented hips. This analysis described a state-wide quality improvement project to reduce fracture and early revision.

METHODS

The MARCQI reports data to participants through reports and in-person meetings and incorporated postoperative hip fracture into pay-for-performance incentives as part of a quality improvement project in 2018. The percent of cemented stems and incidence of fracture within 90 days of surgery were analyzed by age, sex, and year of surgery.

RESULTS

The overall use of cemented stems in THA rose from 2.7% in 2017 to 6.8% in 2022. Only 0.7% of men and 1.8% of women under 75 years were cemented in 2017 while 4.7 and 10.4% of patients 75 years and older were cemented, respectively. By 2022, 10.8% of men and 26.8% of women 75 years and older were cemented. In elderly women, the incidence of fracture after THA has dropped to 1.7% in 2022 from a peak of 3.5% in 2018 as the use of cement has increased.

CONCLUSIONS

Early fracture often leads to revision and may be preventable. This analysis demonstrated a direct correlation between the use of cemented stems and decreased postoperative fracture rates in elderly women. State-wide fractures increased from 2012 to 2018 (peak at 1.3%). Since the beginning of the MARCQI fracture reduction quality initiative, there has been a steady decline to 0.96% in 2022. Stratifying by age and sex, cementing in older women increased by 16%, and fracture rates decreased by nearly 2%. With this MARCQI initiative, there were an estimated 280 fewer revisions secondary to fractures in Michigan. Surgeons should consider using cemented femoral stems for THA in elderly women.

Purified bone xenografts: A novel and efficient animal bone substitute derived from an optimized supercritical CO2 treatment

Bone xenografts represent a promising alternative to autologous or allograft transplants, yet antigenicity in animal-derived tissues remains a major limitation to their clinical use. To provide any risk of contamination or allogenic rejection, the Supercrit® process was developed to treat allogeneic human bone combining a supercritical CO2 treatment followed by a chemical treatment using high quantities of different solvents. The aim of this study was to produce a xenogeneic bone substitute thanks to the development of a new one-step supercritical process, 'Goxcrit', and to test it in vivo. This new process reduces the use of solvents by injecting them under pressure into the supercritical CO2 flow, while maintaining the cleaning quality of the bone matrix and better preserving its inner structure, essential for its future bone integration. Porcine derived bone samples were treated using Goxcrit or Supercrit®, and compared with human bone treated with Supercrit®, the commercialized bone allograft. In vitro analyses demonstrated the absence of cytotoxicity and of the alpha-gal epitope mainly responsible for cross-species immunogenicity. Additionally, in vivo experiments revealed improved bone formation in rats critical calvarial defects (BV/TV and von Kossa analyses) implanted with Goxcrit samples, with bone remodeling (TRAP/ALP stains), compared to those treated with Supercrit®. These results can be attributed to the less aggressive chemical process of the Goxcrit, which preserves the bone's inner structure critical for remodeling. Our study highlighted the interest of using a porcine bone source treated with the Goxcrit process to meet the growing demand for reliable and effective bone substitutes.

37-Day microgravity exposure in 16-Week female C57BL/6J mice is associated with bone loss specific to weight-bearing skeletal sites

Exposure to weightlessness in microgravity and elevated space radiation are associated with rapid bone loss in mammals, but questions remain about their mechanisms of action and relative importance. In this study, we tested the hypothesis that bone loss during spaceflight in Low Earth Orbit is primarily associated with site-specific microgravity unloading of weight-bearing sites in the skeleton. Microcomputed tomography and histological analyses of bones from mice space flown on ISS for 37 days in the NASA Rodent Research-1 experiment show significant site-specific cancellous and cortical bone loss occurring in the femur, but not in L2 vertebrae. The lack of bone degenerative effects in the spine in combination with same-animal paired losses in the femur suggests that space radiation levels in Low Earth Orbit or other systemic stresses are not likely to significantly contribute to the observed bone loss. Remarkably, spaceflight is also associated with accelerated progression of femoral head endochondral ossification. This suggests the microgravity environment promotes premature progression of secondary ossification during late stages of skeletal maturation at 21 weeks. Furthermore, mice housed in the NASA ISS Rodent Habitat during 1g ground controls maintained or gained bone relative to mice housed in standard vivarium cages that showed significant bone mass declines. These findings suggest that housing in the Rodent Habitat with greater topological enrichment from 3D wire-mesh surfaces may promote increased mechanical loading of weight-bearing bones and maintenance of bone mass. In summary, our results indicate that in female mice approaching skeletal maturity, mechanical unloading of weight-bearing sites is the major cause of bone loss in microgravity, while sites loaded predominantly by muscle activity, such as the spine, appear unaffected. Additionally, we identified early-onset of femoral head epiphyseal plate secondary ossification as a novel spaceflight skeletal unloading effect that may lead to premature long bone growth arrest in microgravity.

Biomechanical perspectives on image-based hip fracture risk assessment: advances and challenges

Hip fractures pose a significant health challenge, particularly in aging populations, leading to substantial morbidity and economic burden. Most hip fractures result from a combination of osteoporosis and falls. Accurate assessment of hip fracture risk is essential for identifying high-risk individuals and implementing effective preventive strategies. Current clinical tools, such as the Fracture Risk Assessment Tool (FRAX), primarily rely on statistical models of clinical risk factors derived from large population studies. However, these tools often lack specificity in capturing the individual biomechanical factors that directly influence fracture susceptibility. Consequently, image-based biomechanical approaches, primarily leveraging dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT), have garnered attention for their potential to provide a more precise evaluation of bone strength and the impact forces involved in falls, thereby enhancing risk prediction accuracy. Biomechanical approaches rely on two fundamental components: assessing bone strength and predicting fall-induced impact forces. While significant advancements have been made in image-based finite element (FE) modeling for bone strength analysis and dynamic simulations of fall-induced impact forces, substantial challenges remain. In this review, we examine recent progress in these areas and highlight the key challenges that must be addressed to advance the field and improve fracture risk prediction.

Raman Spectroscopy Detects Bone Mineral Changes with Aging in Archaeological Human Lumbar Vertebrae from Thornton Abbey

Archaeological human remains provide key insight into lifestyles, health, and diseases affecting past societies. However, only limited analyses can be conducted without causing damage due to the destructive nature of current technologies. The same problem exists with current clinical analyses of the skeleton, and the preferred advanced imaging techniques only provide macroscopic information. Raman spectroscopy could provide chemical information without detriment to archaeological bone samples and perhaps the need for invasive diagnostic procedures in the future. This study measured archaeological human vertebrae to investigate if chemical differences with aging were detectable with Raman spectroscopy and if differences in mineral chemistry could contribute to information on bone mineral diseases. The three lowest bones of the spine (lumbar vertebrae L3-L5), which are subject to the heaviest loading in life, of nine adults from three age groups (18-25, 25-45, and 45+ years) were provided by the Thornton Abbey Project. Three biomechanically important anatomical locations were selected for analysis; likely sites chosen to measure any chemical changes associated with aging, the vertebral body center and the zygapophyseal joints. Results detected chemical changes associated with aging. These changes relate to the minerals phosphate (∼960 cm-1) and carbonate (∼1070 cm-1), which are fundamental to bone function. Overall mineralization was found to increase with aging, but while carbonate increased with age, phosphate increased up to ∼45 years and then declined. These fluctuations were found in all three vertebrae, but were more distinct in L5, particularly in the vertebral body, indicating this is an optimal area for detecting bone mineral chemistry changes with aging. This is the first Raman analysis of bone samples from the historically significant site of Thornton Abbey. Results detected age-related changes, illustrating that ancient remains can be used to enhance understanding of modern diseases and provide information on the health and lifestyle of historic individuals.

The Impact of Fermented Dairy Products and Probiotics on Bone Health Improvement

The bone is an important body organ due to its role in locomotion, protection and mineral homeostasis. Bone health is affected by various intrinsic and extrinsic factors like genetics, diet, environment and immune status of an individual. Being a dynamic organ, bones are continuously being remodeled and the remodeling is mediated by an intricate balance of bone formation and resorption which, in turn, are regulated by environmental, genetic, hormonal and neural factors. Lack of balance in any of these factors leads to bone disorders such as osteoporosis. Fermented dairy products along with their probiotics content play a significant role in bone remodeling process ensuring the maintenance of intricate balance in bone forming cells (osteoblasts) and bone resorbing cells (osteoclasts). Proteins and various minerals are important constituents of bone. Dairy products, especially fermented ones, are significant because of being a good source of proteins and minerals required to make and maintain a healthy bone. In addition, these provide the body with probiotics which are involved in bone health improvement by enhancing the bioavailability of dietary constituents, production of short chain fatty acids and reducing the inflammatory components. Hence, fermented dairy products should be a regular part of our diet to keep our bone healthy.

Age-Related Oral and Para-Oral Tissue Disorders: The Evolving Therapeutic and Diagnostic Potential of Exosomes

This review highlights the key molecular and cellular mechanisms contributing to aging, such as DNA damage, mitochondrial dysfunction, telomere shortening, protein dysfunction, and defective autophagy. These biological mechanisms are involved in various oral health conditions prevalent in the elderly, including periodontal disease, oral cancer, xerostomia, dental caries, and temporomandibular joint disorders. Exosomes generated by mesenchymal stem cells possess substantial therapeutic potential. These exosomes are nanosized extracellular vesicles derived from cells and are involved in essential intercellular communication and tissue homeostasis. The exosome-based therapies proved superior to traditional cell-based approaches, due to lower immunogenicity, ease of storage, and avoidance of complications associated with cell transplantation. Furthermore, the diagnostic potential of exosomes as non-invasive biomarkers for aging processes and age-related oral diseases offers insights into disease diagnosis, staging, and monitoring. Among the challenges and future perspectives of translating exosome research from preclinical studies to clinical applications is the need for standardized procedures to fully harness the therapeutic and diagnostic capabilities of exosomes.

Aging-Induced Discrepant Response of Fracture Healing is Initiated from the Organization and Mineralization of Collagen Fibrils in Callus

Fracture healing is a complex process during which the bone restores its structural and mechanical integrity. Collagen networks and minerals are the fundamental components to rebuild the bone matrix in callus. It has been recognized that bone quality could be impaired during aging. However, how the structural and mechanical recovery of fracture healing is influenced by aging, particularly from the perspective of organization and mineralization of the collagen network in callus, remains unclear. A tibial fracture model was established for both the young (5 weeks) and aged mice (68 weeks). On the 21st day postfracture, the characteristics of the collagen network, mineralization, and the nanoscale mechanical properties of the callus were assessed. The results indicated that aging postpones the fracture healing process, leading to incomplete microstructure, less mineral content and mineralization, and weaker mechanical properties of callus. In the aged mice, the internal fixation and mechanical immobilization promoted the mineralization of callus by increasing mineral crystal length and mineral-to-matrix ratio by 48 and 42% compared to the internal fixation and free movement control group, respectively. By contrast, in the young mice, the internal fixation and mechanical immobilization induced disordered collagen fibrils and decreased the crystal length and mineral-to-matrix ratio by 32 and 36%, compared to the internal fixation and free movement control group, respectively. The present findings suggested that the aging-induced structure and mechanical differences of callus during fracture healing initiate from the organization and mineralization of collagen fibrils. Multiscale structural and mechanical analysis suggested mechanical immobilization is beneficial to the structure, composition, and mechanics of callus in the aged mice while impairing the organization and mineralization of collagen fibril in the callus of the young mice. These findings suggested that different mechanical intervention strategies should be adopted for fracture healing at different ages, which provides valuable insights for the clinical treatment of bone fracture.

Melatonin alleviates senile osteoporosis by regulating autophagy and enhancing fracture healing in aged mice

Aims

In our previous research, we have found that melatonin (MEL) affects the osteoporotic process. By balancing bone remoulding, autophagy is involved in age-related bone loss. However, as a regulator of autophagy, whether MEL influences senile osteoporosis via regulating autophagy remains unclear.

Methods

Cellular, radiological, and histopathological evaluations were performed on 36 16-month-old male C57BL6/L mice or aged bone marrow-derived mesenchymal stem cells. A MEL-gelatin methacrylamide system was constructed to aid osteoporotic fracture healing.

Results

In this study, we found that bone loss, low level of MEL, and decreased autophagy coexisted in aged C57BL6/L mice. A physiological (low, 10 nM but not 100 nM) concentration of MEL restored bone loss, transformed the cytokine framework, and increased the autophagic level in aged mice, whereas inhibition of autophagy unfavourably reduced the positive effects of MEL on bone mass. The autophagy-conducted increased osteogenic lineage commitment and extracellular matrix mineralization, but not matrix synthesis of aged bone marrow-derived mesenchymal stem cells, was responsible for MEL anabolic effects on bone. PIK3C-AKT-MTOR signal was tested to be a main pathway that is involved in MEL-induced autophagy.

Conclusion

Our data suggest that the application of MEL can restore degenerative osteogenesis of aged bone marrow-derived mesenchymal stem cells, and has the potential to regain bone mass in aged mice through activating autophagy via the PIK3C-AKT-MTOR pathway. MEL therefore may serve as a potential clinical therapy to treat senile osteoporosis.

Microplastics in human skeletal tissues: Presence, distribution and health implications

Although microplastics have been detected in human blood, placenta and other tissues. In this study, for the first time, we characterized the presence and variation of microplastic deposition patterns in three human skeletal tissues, namely the bone, cartilage, and intervertebral discs. Forty microplastic fragments were observed in 24 samples from the bone, cartilage, and intervertebral disc, ranging from 25.44 to 407.39 μm in diameter. The deposition abundance of microplastics in the human intervertebral disc (61.1 ± 44.2 particles/g) was higher than those in the bone (22.9 ± 15.7 particles/g) and cartilage tissue (26.4 ± 17.6 particles/g). The average sizes of microplastics in intervertebral discs (159.5 ± 103.8 μm) and bone (138.86 ± 105.67 μm) were larger than that in the cartilage tissue (87.5 ± 30.7 μm). The most frequently identified polymers were polypropylene (35 %), ethylene vinyl acetate copolymer (30 %), and polystyrene (20 %). The in vivo experiment suggested that microplastics invaded the bone, cartilage, and intervertebral discs through blood circulation after 4 weeks of exposure. Serum levels of tumor necrosis factor-α (TNF-α), Type Ⅰ procollagen amino-terminal peptide (PINP), and tartrate-resistant acid phosphatase-5b (TRACP-5b) were elevated compared with those in the control group (p < 0.05). Our study suggests that microplastics invade the bone, cartilage, and intervertebral discs through the blood supply, causing distinct patterns of microplastic accumulation in these regions. Microplastic invasion can affect skeletal health by influencing the expression of inflammatory and bone morphogenetic cytokines. These findings provide insights into investigating the impact of microplastics on human skeletal health.

The Role of Fe, S, P, Ca, and Sr in Porous Skeletal Lesions: A Study on Non-adult Individuals Using pXRF

Portable X-ray fluorescence is a new tool in the study of human bone. This research aims to investigate if variations in bone elemental concentrations are related with porous skeletal lesions (PSLs). One hundred well-preserved non-adult skeletons aged 0-11 years were selected from the archaeological site Convent of São Domingos, Lisbon (18th-19th century). Measuring a standard reference material and calculating the technical error of measurement assured elemental data reliability. Moreover, measuring soil samples excluded possible contamination of bones with elements from the soil, except for Pb. Additionally, the Ca/P ratio indicates maintenance of bone integrity. Cribra cranii, orbitalia, humeralis, and femoralis were recorded as present/absent, and the estimated intra-/inter-observer errors were low. The multivariate analysis found higher odds of having cribra orbitalia (OR = 1.76; CI = 0.97-3.20) and cribra femoralis (OR = 1.42; CI = 0.73-2.74) in individuals with lower Fe and higher S. Furthermore, higher levels of P, Ca, and Sr increased the odds of individuals developing cribra femoralis (OR = 2.30; CI = 1.23-4.29). Age also correlated with increased odds of exhibiting cribra orbitalia (OR = 1.86; CI = 0.94-3.68), cribra femoralis (OR = 6.97; CI = 2.78-17.45), and cribra humeralis (OR = 8.32; CI = 2.71-25.60). These findings suggest a shared etiology for these three cribras, contrasting with the higher Fe levels in individuals with cribra cranii. Lower Fe and higher S levels in individuals with cribra suggest a complex etiology, possibly involving conditions like megaloblastic or chronic disease anemia(s). Age-related elemental changes support the hypothesis that age influences cribra frequencies. This study highlights PSL complexity and opens new avenues for research.

Sex estimation in a Chilean population by mandibular analysis in cone beam computed tomography images

BACKGROUND

Sex estimation is the first stage in the identification of an individual in the forensic context, and can be carried out from bone structures like the mandible. The aim of this study was to estimate sex from metric analysis of the mandible in cone beam computed tomography images (CBCT) of adult Chilean individuals.

METHODS

Six mandibular measurements were analysed, five linear and one angular, in CBCT of adult Chilean individuals of both sexes. ROC Curve analysis was performed, with cut-off points, and of the overall model quality. Univariate discriminant function analysis was used to determine the accuracy of each measurement for sex estimation. Multivariate discriminant function analysis, both directly and by steps, was used to obtain the predictive value of the mandible including all the measurements.

RESULTS

The data included were 155 CBCT, 105 of females and 50 of males. The mandible presented great sexual dimorphism, with the mandibular ramus presenting greater predictive power than the mandibular body. When each mandibular measurement was analysed separately, the maximum height of the mandibular ramus presented the greatest predictive power (76.5%), while the mandibular angle was the least accurate parameter for sex estimation (58.1%). Direct method analysis presented 87.1% accuracy for sex identification of adult Chilean individuals, and joint analysis of maximum mandibular ramus height (MRH), corono-condylar distance and bigonial breadth presented 86.5% accuracy. In ROC Curve analysis the MRH was the variable with the greatest discriminating capacity (AUC = 0.833), MA was the only variable which presented no discriminating capacity (AUC = 0.386) and also presented low quality in model quality analysis.

CONCLUSION

Metric analysis of the mandible in CBCT images presents an acceptable accuracy for sex estimation in Chilean individuals, and its use for that purpose in forensic practice is recommended.

Mandibular trabecular bone pattern before and two years after medical or surgical obesity treatment in young Swedish women

OBJECTIVE

To investigate if changes in body mass index (BMI) result in changes of the mandibular trabecular bone structure.

MATERIALS AND METHODS

Females (18-35 years at baseline, mean BMI 42,3) were followed from before (n = 117) until two years (n = 66) after obesity treatment (medical or surgical). The mandibular bone trabeculation was classified as sparse, dense, or mixed on intraoral radiographs (Lindh's index). A digitized method (Jaw-X) assessed the size and intensities of intertrabecular spaces. The main predictor variable was BMI reduction over the period.

RESULTS

Before treatment, the group with a high BMI (≥ 45) had a significantly denser bone than those with a lower BMI (p = 0.035). Two years after treatment, fewer were classified with sparse bone (Lindh's index p = 0.001, Jaw-X p = 0.009). The physical activity increased with fewer having a sedentary lifestyle (40% before, 17% after treatment). The association between BMI reduction and the difference in Jaw-X was significant in regression models and not influenced by obesity treatment method but by baseline factors as age, trabecular bone pattern and level of ionized calcium.

CONCLUSIONS

Before obesity treatment, high BMI was associated with dense bone trabeculation in the jaw. The group with sparse bone had decreased at follow-up. The association between BMI reduction and bone trabeculation was influenced by individual and medical factors.

CLINICAL RELEVANCE

Bone trabeculation in the mandible was maintained during the first years after obesity treatment but new health habits should be encouraged, and patients need to be monitored and followed up further.

Regulating Mitochondrial Aging via Targeting the Gut-Bone Axis in BMSCs With Oral Hydrogel Microspheres to Inhibit Bone Loss

The gut-bone axis is a promising target for osteoporosis treatment, yet existing delivery systems lack precise targeting. Herein, an oral hydrogel microsphere system (E7-Lipo@Alg/Cs) is developed using gas microfluidic and ionic crosslinking technologies to deliver drugs to bone marrow mesenchymal stem cells (BMSCs) via the gut-bone axis, regulating mitochondrial aging. A BMSC-affine peptide is conjugated onto liposomes encapsulating Fisetin, followed by incorporation into alginate-calcium hydrogel microspheres. Chitosan is electrostatically adsorbed onto the microsphere surface, creating a core-shell structure that adheres to intestinal epithelial cells, withstands gastric acid, and facilitates targeted delivery to BMSCs through the intestinal-bone axis. In vitro, the system effectively enhances mitochondrial function and reverses BMSC aging, while in vivo studies demonstrate prolonged drug activity, restored osteogenic differentiation, and bone regeneration. RNA-seq indicates activation of the AMPK-SIRT1 pathway, reversing mitochondrial aging in BMSCs and promoting aged bone tissue regeneration. This oral hydrogel microsphere system provides a targeted and efficient strategy for regulating mitochondrial function and preventing bone loss, offering significant clinical potential for osteoporosis treatment.

High-resolution three-dimensional micro-computed tomography assessment of micro-architectural patterns in non-adults with cribra orbitalia: Correlation between macro- and micro-scale bone features

Skeletal porous lesions such as cribra orbitalia (CO) have long been of interest to bioanthropologists worldwide, mainly due to their high prevalence in osteological material. Previous studies considered CO as an external morphological manifestation, and therefore, research has mainly focused on visible (macroscopic) CO patterns. However, the understanding of CO-induced micro-scale bone changes is still scarce. Therefore, we performed high-resolution micro-computed tomography imaging to investigate three-dimensional CO-induced micro-architectural patterns in non-adults, with a particular focus on the correlation between macroscopic and micro-architectural orbital features. Cortical and trabecular micro-architectural changes in the orbital roof were analyzed in non-adults younger than 15 years, using orbital roof samples with and without macroscopic traces of CO (n = 28). A widely accepted five-grade macroscopic CO scoring system was applied to analyze CO severity. Areas affected with CO (area 1) and areas without macroscopic CO traces (area 2) were analyzed separately. The conducted high-resolution analysis showed that cortical and trabecular micro-architecture varied with CO presence, lesion severity (CO grade), and the analyzed area. Inter-grade comparisons suggested that most of the analyzed micro-architectural parameters were not significantly different between adjacent CO grades. Based on the micro-architectural evaluation of areas 1 and 2, the porous lesions were much more extensive than revealed by gross examination. In addition, micro-architectural differences were particularly pronounced in younger non-adults. In summary, our pilot study suggests that the macroscopic examination of CO reflects only the tip of the iceberg, as the micro-architectural changes seem to be much larger than macroscopically identified. RESEARCH HIGHLIGHTS: Cribra orbitalia (CO) represents orbital porous lesions. A high-resolution microscopic assessment of CO-induced changes in non-adults was done by micro-computed tomography. The microarchitecture was affected by CO presence, CO grade, area, and age.

Characteristics and outcomes of inpatients aged 85 and older with thoracolumbar vertebral fractures: impact on hospital stay and mortality

BACKGROUND

There is a gap in evidence about medical outcomes in oldest-old patients (aged 85 and older) with vertebral fractures (VFs). The aim of this study was to evaluate the impact of patient and fracture characteristics on "short-term" hospital outcomes.

METHODS

All patients aged ≥ 85 presenting an acute or subsequent VF at our single level I spine center between 2019 and 2021 requiring hospital treatment were included. The data collection was conducted retrospectively. The primary parameters of interest were length of stay (LOS) and in-hospital mortality. Further outcome parameters were the occurrence of general (non-operative) complications and Intensive Care Unit (ICU) admission. For statistical analysis, linear and binary logistic regression modeling were performed.

RESULTS

A total of 153 patients with an average age of 88.5 (range 85 to 99) met the inclusion criteria. Our patients were mostly female (68.6%) and moderately comorbid according to a Charlson Comorbidity Index (CCI) of 2.9. 58.8% had diagnosed osteoporosis. Fracture morphologies represented as "Osteoporotic Fracture" (OF) classification types were of central importance for undergoing operative treatment (OP) (p < 0.001), necessity for intensive care (p = 0.023), LOS (p = 0.014), and mortality (p = 0.018). 38.6% had OP. We recorded a complication rate of 59.5%, which highly influenced (p < 0.001) both primary outcome parameters. Overall, patients stayed 14.6 days with a mortality of 11.1%.

CONCLUSION

VFs are a severe event in oldest-old patients with a crucial risk of poor medical outcomes during hospitalization. The fracture morphologies are of central importance. However, little is known about the hospital stay of oldest-old inpatients with VFs. Considering an aging population, further investigations would be recommended.

Neurogenic Aging After Spinal Cord Injury: Highlighting the Unique Characteristics of Aging After Spinal Cord Injury

Emanating from several decades of study into the effects of the aging process after spinal cord injury (SCI), "accelerated aging" has become a common expression as the SCI accelerates the onset of age-related pathologies. However, the aging process follows a distinct trajectory, characterized by unique patterns of decline that differ from those observed in the general population without SCI. Aging brings significant changes to muscles, bones, and hormones, impacting overall physical function. Muscle mass and strength begin to decrease with a reduction in muscle fibers and impaired repair mechanisms. Bones become susceptible to fractures as bone density decreases. Hormonal changes combined with decreased physical activity accelerate the reduction of muscle mass and increase in body fat. Muscle atrophy and skeletal muscle fiber type transformation occur rapidly and in a unique pattern after SCI. Bone loss develops more rapidly and results in an increased risk of fractures in body regions unique to individuals with SCI. Other factors, such as excessive adiposity, decreased testosterone and human growth hormone, and increased systemic inflammation, contribute to a higher risk of neuropathically driven obesity, dyslipidemia, glucose intolerance, insulin resistance, and increasing cardiovascular disease risk. Cardiorespiratory changes after SCI result in lower exercise heart rates, decreased oxygenation, and mitochondrial dysfunction. While it is important to acknowledge the accelerated aging processes after SCI, it is essential to recognize the distinct differences in the aging process between individuals without physical disabilities and those with SCI. These differences, influenced by neuropathology, indicate that it may be more accurate to describe the aging process in individuals with chronic SCI as neurogenic accelerated aging (NAA). Research should continue to address conditions associated with NAA and how to ameliorate the accelerated rate of premature age-related conditions. This review focuses on the NAA processes and the differences between them and the aging process in those without SCI. Recommendations are provided to help slow the development of premature aging conditions.

Impact of Particle Size and Sintering Temperature on Calcium Phosphate Gyroid Structure Scaffolds for Bone Tissue Engineering

Due to the chemical composition and structure of the target tissue, autologous bone grafting remains the gold standard for orthopedic applications worldwide. However, ongoing advancements in alternative grafting materials show that 3D-printed synthetic biomaterials offer many advantages. For instance, they provide high availability, have low clinical limitations, and can be designed with a chemical composition and structure comparable to the target tissue. This study aimed to compare the influences of particle size and sintering temperature on the mechanical properties and biocompatibility of calcium phosphate (CaP) gyroid scaffolds. CaP gyroid scaffolds were fabricated by 3D printing using powders with the same chemical composition but different particle sizes and sintering temperatures. The physicochemical characterization of the scaffolds was performed using X-ray diffractometry, scanning electron microscopy, and microtomography analyses. The immortalized human mesenchymal stem cell line SCP-1 (osteoblast-like cells) and osteoclast-like cells (THP-1 cells) were seeded on the scaffolds as mono- or co-cultures. Bone cell attachment, number of live cells, and functionality were assessed at different time points over a period of 21 days. Improvements in mechanical properties were observed for scaffolds fabricated with narrow-particle-size-distribution powder. The physicochemical analysis showed that the microstructure varied with sintering temperature and that narrow particle size distribution resulted in smaller micropores and a smoother surface. Viable osteoblast- and osteoclast-like cells were observed for all scaffolds tested, but scaffolds produced with a smaller particle size distribution showed less attachment of osteoblast-like cells. Interestingly, low attachment of osteoclast-like cells was observed for all scaffolds regardless of surface roughness. Although bone cell adhesion was lower in scaffolds made with powder containing smaller particle sizes, the long-term function of osteoblast-like and osteoclast-like cells was superior in scaffolds with improved mechanical properties.

Senoinflammation as the underlying mechanism of aging and its modulation by calorie restriction

Senoinflammation is characterized by an unresolved low-grade inflammatory process that affects multiple organs and systemic functions. This review begins with a brief overview of the fundamental concepts and frameworks of senoinflammation. It is widely involved in the aging of various organs and ultimately leads to progressive systemic degeneration. Senoinflammation underlying age-related inflammation, is causally related to metabolic dysregulation and the formation of senescence-associated secretory phenotype (SASP) during aging and age-related diseases. This review discusses the biochemical evidence and molecular biology data supporting the concept of senoinflammation and its regulatory processes, highlighting the anti-aging and anti-inflammatory effects of calorie restriction (CR). Experimental data from CR studies demonstrated effective suppression of various pro-inflammatory cytokines and chemokines, lipid accumulation, and SASP during aging. In conclusion, senoinflammation represents the basic mechanism that creates a microenvironment conducive to aging and age-related diseases. Furthermore, it serves as a potential therapeutic target for mitigating aging and age-related diseases.

Shining light on the Mary Rose: Identifying chemical differences in human aging and handedness in the clavicles of sailors using Raman spectroscopy

The Mary Rose, for many years the flagship of the Tudor king, Henry VIII, sank during the battle of the Solent on the 19th July 1545. 437 years later, the remains of the hull and associated contents were recovered following a four-year excavation, all dated to a precise point in history. The assemblage is a valuable resource, as the environment preserved over 19,000 objects and the remains of a minimum of 179 crew members. This remarkable preservation allows for the crew of the Mary Rose to be studied holistically; their belongings, appearance, and even their health. Using Raman spectroscopy, this study investigated the clavicle bone chemistry of 12 men, aged 13-40, who died on the Mary Rose. Specifically looking at any changes with age or that could be linked to handedness. Results found that bone mineral increased with age and bone protein decreased. The mineral increase was found to be more substantial than the protein decrease. When the left and right side were considered, these findings maintained and were more pronounced in the right clavicle. This suggests that handedness influences clavicle bone chemistry; offering an important modern consideration for fracture risk. These results enhance our understanding of the lives of Tudor sailors, but also contribute to modern scientific investigation in the drive for a clearer understanding of changes in bone chemistry and potential links to aging related skeletal diseases such as osteoarthritis.

Lead Toxicity and Maternal Exposure: Characterisation of Alveolar Bone Changes on Offspring Rats

Lead poisoning is a global public health concern. Maternal exposure during intrauterine and lactational periods can present a higher susceptibility of harm to the offspring. Thus, pregnant female Wistar rats (Rattus norvegicus) were randomly divided in two experimental groups: control group and Lead group. The animals were exposed to 50 mg/kg of Lead Acetate daily for 42 days (21 days of gestational period + 21 days of lactational period). After the exposure period, the mandibles of the offspring were collected for lead quantification, Raman spectroscopy analysis, micro-CT, morphometric e histochemical analysis. Lead exposure altered the physical-chemical composition of alveolar bone and caused histological damage associated with a reduction in osteocyte density and collagen area fraction, increase in collagen maturity, as well as a reduction in bone volume fraction. An increase in trabecular spaces with anatomical compromise of the vertical dimensions of the bone was observed. Thus, the results suggest that developing alveolar bone is susceptible to toxic effects of lead when organisms are exposed during intrauterine and lactation periods.

Single missing molar with wide mesiodistal length restored using a single or double implant-supported crown: A self-controlled case report and 3D finite element analysis

PURPOSE

Based on a self-controlled case, this study evaluated the finite element analysis (FEA) results of a single missing molar with wide mesiodistal length (MDL) restored by a single or double implant-supported crown.

METHODS

A case of a missing bilateral mandibular first molar with wide MDL was restored using a single or double implant-supported crown. The implant survival and peri-implant bone were compared. FEA was conducted in coordination with the case using eight models with different MDLs (12, 13, 14, and 15 mm). Von Mises stress was calculated in the FEA to evaluate the biomechanical responses of the implants under increasing vertical and lateral loading, including the stress values of the implant, abutment, screw, crown, and cortical bone.

RESULTS

The restorations on the left and right sides supported by double implants have been used for 6 and 12 years, respectively, and so far have shown excellent osseointegration radiographically.The von Mises stress calculated in the FEA showed that when the MDL was >14 mm, both the bone and prosthetic components bore more stress in the single implant-supported strategy. The strength was 188.62-201.37 MPa and 201.85-215.9 MPa when the MDL was 14 mm and 15 mm, respectively, which significantly exceeded the allowable yield stress (180 MPa).

CONCLUSIONS

Compared with the single implant-supported crown, the double implant-supported crown reduced peri-implant bone stress and produced a more appropriate stress transfer model at the implant-bone interface when the MDL of the single missing molar was ≥14 mm.

Healing sequelae following tooth extraction and dental implant placement in an aged, ovariectomy model

At present, a lack of consensus exists regarding the clinical impact of osteoporosis on alveolar bone metabolism during implant osseointegration. While limited preclinical and clinical evidence demonstrates a negative influence of osteoporosis on dental extraction socket healing, no preclinical studies offer data on the results of implant placement in 6-mo-old, ovariectomized (OVX) Sprague-Dawley rats. This study aimed to investigate the outcomes of dental tooth extraction socket healing and implant placement in a rodent model of osteoporosis following daily vehicle (VEH) or abaloparatide (ABL) administration. Micro-CT and histologic analysis demonstrated signs of delayed wound healing, consistent with alveolar osteitis in extraction sockets following 42 d of healing in both the VEH and ABL groups. In a semiquantitative histological analysis, the OVX-ABL group demonstrated a tendency for improved socket regeneration with a 3-fold greater rate for moderate socket healing when compared to the OVX-VEH group (43% vs 14%), however, this finding was not statistically significant (p=.11). No significant differences were observed between vehicle and test groups in terms of implant outcomes (BMD and bone volume/total volume) at 14- and 21-d post-implant placement. Abaloparatide (ABL) significantly increased BMD of the femoral shaft and intact maxillary alveolar bone sites in OVX animals, demonstrating the therapeutic potential for oral hard tissue regeneration. The present model involving estrogen-deficiency-induced bone loss demonstrated an impaired healing response to dental extraction and implant installation.

The age-related effects on orthodontic tooth movement and the surrounding periodontal environment

Orthodontic treatment in adults is often related to longer treatment time as well as higher periodontal risks compared to adolescents. The aim of this review is to explore the influence of age-related chages on orthodontic tooth movement (OTM) from macro and micro perspectives. Adults tend to show slower tooth movement speed compared to adolescence, especially during the early phase. Under orthodontic forces, the biological responses of the periodontal ligament (PDL) and alveolar bone is different between adult and adolescents. The adult PDL shows extended disorganization time, increased cell senescence, less cell signaling and a more inflammatory microenvironment than the adolescent PDL. In addition, the blood vessel surface area is reduced during the late movement phase, and fiber elasticity decreases. At the same time, adult alveolar bone shows a higher density, as well as a reduced osteoblast and osteoclast activation, under orthodontic forces. The local cytokine expression also differs between adults and adolescents. Side-effects, such as excessive root resorption, greater orthodontic pain, and reduced pulpal blood flow, also occur more frequently in adults than in adolescents.

Targeting miR-29 mitigates skeletal senescence and bolsters therapeutic potential of mesenchymal stromal cells

Mesenchymal stromal cell (MSC) senescence is a key factor in skeletal aging, affecting the potential of MSC applications. Identifying targets to prevent MSC and skeletal senescence is crucial. Here, we report increased miR-29 expression in bone tissues of aged mice, osteoporotic patients, and senescent MSCs. Genetic overexpression of miR-29 in Prx1-positive MSCs significantly accelerates skeletal senescence, reducing cortical bone thickness and trabecular bone mass, while increasing femur cross-sectional area, bone marrow adiposity, p53, and senescence-associated secretory phenotype (SASP) levels. Mechanistically, miR-29 promotes senescence by upregulating p53 via targeting Kindlin-2 mRNA. miR-29 knockdown in BMSCs impedes skeletal senescence, enhances bone mass, and accelerates calvarial defect regeneration, also reducing lipopolysaccharide (LPS)-induced organ injuries and mortality. Thus, our findings underscore miR-29 as a promising therapeutic target for senescence-related skeletal diseases and acute inflammation-induced organ damage.

Exploring depression, comorbidities and quality of life in geriatric patients: a study utilizing the geriatric depression scale and WHOQOL-OLD questionnaire

BACKGROUND

The increasing prevalence of depression among older adults is a growing concern. Chronic health conditions, cognitive impairments, and hospitalizations amplify emotional distress and depression levels in this population. Assessing the quality of life is crucial for the well-being of older adults.

AIMS

Our study aimed to examine how comorbidities affect depression and quality of life in geriatric patients in both outpatient and hospital settings.

METHODS

100 patients (50 from internal medicine outpatient clinic and 50 from internal medicine ward) were included in the study according to inclusion and exclusion criteria. Patients were classified into different age groups (65-74 years, 75-84 years and ≥ 85 years). Data on patients' location of application, age, sex, living alone or with family status, number of comorbid diseases, types of accompanying diseases were recorded and WHOQOL-OLD and Geriatric Depression Scale (GDS) questionnaires were administered. Results were evaluated using SPSS.

RESULTS

The WHOQOL-OLD questionnaire score was higher in the 65-74 age group compared to other groups, but there was no significant difference between outpatient group and hospitalized group. Patients with comorbid diseases had lower WHOQOL-OLD questionnaire scores compared to those without comorbid diseases. In the 75-84 and ≥ 85 age groups, the GDS scores were higher compared to the 65-74 age group. In hospitalized group, GDS scores were higher than outpatient clinic group. In patients with comorbid diseases, GDS scores were higher than the ones without comorbid diseases.

DISCUSSION

Our findings indicate that quality of life is higher among those aged 65-74, with lower incidence of depression compared to other age groups. Hospitalization correlates with higher depression rates but not quality of life. As number of comorbid diseases increases in older adults, the frequency of depression rises and the quality of life declines.

CONCLUSIONS

Early detection and intervention for depression are crucial for enhancing older adults' well-being.

Comparing Bone Graft Success, Implant Survival Rate, and Marginal Bone Loss: A Retrospective Study on Materials and Influential Factors

Bone grafting serves to restore the alveolar bone defect, providing adequate alveolar bone essential for long-term implant survival. This retrospective study aimed to evaluate the success rate of guided bone regeneration (GBR) bone grafting and investigate the survival rate of implants and the degree of marginal bone loss (MBL) around implants. Furthermore, the influence of confounding factors such as patient conditions, bone graft properties, and implant characteristics was assessed. This study was carried out on treatment outcomes of patients with implants between January 2007 and December 2016, using various graft materials, including autograft, allograft, and xenograft. In a mean follow-up of 70 months (range: 3-10 years), the overall success rate of bone graft (n = 80) was 100%, and the overall survival rate of implant (n = 107) was 97.2% (autograft: 100%, allograft: 100%, and xenograft: 92.9%; P = .03). Mean MBL up to 3 years after implant installation were similar among graft materials, with 0.84 ± 0.48 mm in autograft, 0.73 ± 0.42 mm in allograft, and 1.01 ± 0.59 mm in xenograft (P = .14). Posterior mandibular location had a significant influence on implant survival (P = .003). A significant association of MBL with several factors, including age >60 years (P = .03), both diabetes and hypertension (P = .02), without receiving adjunctive membrane (P = .04), loading within 3-6 months (P < .001), and screw-retained crown (P = .008), was confirmed. Our data substantiated that implant rehabilitation with GBR using autograft and allograft provides the most predictable results. The factors above should be carefully considered with xenograft to enhance long-term clinical outcomes.

Using portable X-ray fluorescence elemental analysis to explore porous skeletal lesions: Interplay of sex, age at death, and cause of death

OBJECTIVES

Search for possible associations between bone elemental concentration and the presence of porous skeletal lesions (PSLs), considering the sex, age, and cause of death (COD) of the individuals.

MATERIALS AND METHODS

The sample comprised 107 non-adult individuals (56 females, 51 males) aged 0-20 (x̄ = 13.2, SD = 5.8) from the Coimbra and Lisbon Identified Skeletal Collections. Cribra cranii, orbitalia, humeralis, and femoralis were recorded as present/absent, and elemental concentrations were assessed by portable x-ray fluorescence (pXRF). A multivariate statistical approach was applied.

RESULTS

Well-preserved skeletons with minimal diagenesis showed no sex-related elemental variations or PSL associations. In contrast, age-at-death correlated with elevated Ca, P, Sr, and Pb levels. Cribra cranii increased with age while other cribra declined post-adolescence. Higher concentrations of Fe and lower of S were linked to cribra cranii. Respiratory infections as COD increased the odds of expressing cribra femoralis (OR = 5.25, CI = 1.25-15.14), cribra cranii (OR = 2.91, CI = 0.97-8.69), and cribra orbitalia (OR = 2.76, CI = 1.06-7.24).

DISCUSSION

Feasible pXRF results and low cribra intraobserver error assure replicability. Elevated Ca, P, and Sr in older individuals may relate to skeletal growth, while increased Pb suggests bioaccumulation. Cribra's increase with age reflects different rates of marrow conversion and bone remodeling. Higher Fe and lower S in individuals with cribra cranii possibly reflects poor nutrition, early alcohol use, and sideroblastic anemia, aligning with 19th-20th-century Portugal's living conditions. Respiratory infections increased cribra expression, revealing intricate interplays among inflammation, anemia(s), marrow expansion, and diet. This research highlights a complex scenario and blazes a new path for cribra interpretation.

Epigenetic regulations of cellular senescence in osteoporosis

Osteoporosis (OP) is a prevalent age-related disease that is characterized by a decrease in bone mineral density (BMD) and systemic bone microarchitectural disorders. With age, senescent cells accumulate and exhibit the senescence-associated secretory phenotype (SASP) in bone tissue, leading to the imbalance of bone homeostasis, osteopenia, changes in trabecular bone structure, and increased bone fragility. Cellular senescence in the bone microenvironment involves osteoblasts, osteoclasts, and bone marrow mesenchymal stem cells (BMSCs), whose effects on bone homeostasis are regulated by epigenetics. Therefore, the epigenetic regulatory mechanisms of cellular senescence have received considerable attention as potential targets for preventing and treating osteoporosis. In this paper, we systematically review the mechanisms of aging-associated epigenetic regulation in osteoporosis, emphasizing the impact of epigenetics on cellular senescence, and summarize three current methods of targeting cellular senescence, which is helpful better to understand the pathogenic mechanisms of cellular senescence in osteoporosis and provides strategies for the development of epigenetic drugs for the treatment of osteoporosis.

Unlocking the potential of stimuli-responsive biomaterials for bone regeneration

Bone defects caused by tumors, osteoarthritis, and osteoporosis attract great attention. Because of outstanding biocompatibility, osteogenesis promotion, and less secondary infection incidence ratio, stimuli-responsive biomaterials are increasingly used to manage this issue. These biomaterials respond to certain stimuli, changing their mechanical properties, shape, or drug release rate accordingly. Thereafter, the activated materials exert instructive or triggering effects on cells and tissues, match the properties of the original bone tissues, establish tight connection with ambient hard tissue, and provide suitable mechanical strength. In this review, basic definitions of different categories of stimuli-responsive biomaterials are presented. Moreover, possible mechanisms, advanced studies, and pros and cons of each classification are discussed and analyzed. This review aims to provide an outlook on the future developments in stimuli-responsive biomaterials.

Immunoengineering Biomaterials for Musculoskeletal Tissue Repair across Lifespan

Musculoskeletal diseases and injuries are among the leading causes of pain and morbidity worldwide. Broad efforts have focused on developing pro-regenerative biomaterials to treat musculoskeletal conditions; however, these approaches have yet to make a significant clinical impact. Recent studies have demonstrated that the immune system is central in orchestrating tissue repair and that targeting pro-regenerative immune responses can improve biomaterial therapeutic outcomes. However, aging is a critical factor negatively affecting musculoskeletal tissue repair and immune function. Hence, understanding how age affects the response to biomaterials is essential for improving musculoskeletal biomaterial therapies. This review focuses on the intersection of the immune system and aging in response to biomaterials for musculoskeletal tissue repair. The article introduces the general impacts of aging on tissue physiology, the immune system, and the response to biomaterials. Then, it explains how the adaptive immune system guides the response to injury and biomaterial implants in cartilage, muscle, and bone and discusses how aging impacts these processes in each tissue type. The review concludes by highlighting future directions for the development and translation of personalized immunomodulatory biomaterials for musculoskeletal tissue repair.

A Review of Histological Techniques for Differentiating Human Bone from Animal Bone

The first step in anthropological study is the positive identification of human remains, which can be a challenging undertaking when bones are broken. When bone pieces from different species are mixed together, it can be crucial to distinguish between them in forensic and archaeological contexts. For years, anthropology and archaeology have employed the histomorphological analysis of bones to evaluate species-specific variations. Based on variations in the dimensions and configuration of Haversian systems between the two groups, these techniques have been devised to distinguish between non-human and human bones. All of those techniques concentrate on a very particular kind of bone, zone, and segment. Histomorphometric techniques make the assumption that there are size, form, and quantity variations between non-humans and humans. The structural components of Haversian bones are significant enough to use discriminant function analysis to separate one from the other. This review proposes a comprehensive literature analysis of the various strategies or techniques available for distinguishing human from non-human bones to demonstrate that histomorphological analysis is the most effective method to be used in the case of inadequate or compromised samples.

Are Age and Trauma Mechanism Associated with Volume Change in the Fractures of the Bony Orbit?

Blowout fractures are common midfacial fractures in which one or several of the bones of orbital vault break. This is usually caused by a direct trauma to the eye with a blunt object such as a fist. Fracturing of the fragile orbital bones can lead to changes in the orbital volume, which may cause enophthalmos, diplopia, and impaired facial aesthetics. Objectives: The aim of this study is to investigate whether there is an association between volume change of the bony orbit and age, gender, or trauma mechanism. Methods: A retrospective study of patients with unilateral blowout or blow-in fractures treated and examined in Päijät-Häme Central Hospital, Lahti, Finland was conducted. Altogether, 127 patients met the inclusion criteria. Their computed tomographs (CT) were measured with an orbit-specific automated segmentation-based volume measurement tool, and the relative orbital volume change between fractured and intact orbital vault was calculated. Thereafter, a statistical analysis was performed. A p-value less than 0.05 was considered significant. Results: We found that relative increase in orbital volume and age have a statistically significant association (p = 0.022). Trauma mechanism and gender showed no significant role. Conclusions: Patient's age is associated with increased volume change in fractures of the bony orbit.

Assessment of Bone Age Based on Hand Radiographs Using Regression-Based Multi-Modal Deep Learning

(1) Objective: In this study, a regression-based multi-modal deep learning model was developed for use in bone age assessment (BAA) utilizing hand radiographic images and clinical data, including patient gender and chronological age, as input data. (2) Methods: A dataset of hand radiographic images from 2974 pediatric patients was used to develop a regression-based multi-modal BAA model. This model integrates hand radiographs using EfficientNetV2S convolutional neural networks (CNNs) and clinical data (gender and chronological age) processed by a simple deep neural network (DNN). This approach enhances the model's robustness and diagnostic precision, addressing challenges related to imbalanced data distribution and limited sample sizes. (3) Results: The model exhibited good performance on BAA, with an overall mean absolute error (MAE) of 0.410, root mean square error (RMSE) of 0.637, and accuracy of 91.1%. Subgroup analysis revealed higher accuracy in females ≤ 11 years (MAE: 0.267, RMSE: 0.453, accuracy: 95.0%) and >11 years (MAE: 0.402, RMSE: 0.634, accuracy 92.4%) compared to males ≤ 13 years (MAE: 0.665, RMSE: 0.912, accuracy: 79.7%) and >13 years (MAE: 0.647, RMSE: 1.302, accuracy: 84.6%). (4) Conclusion: This model showed a generally good performance on BAA, showing a better performance in female pediatrics compared to male pediatrics and an especially robust performance in female pediatrics ≤ 11 years.

Effects of pH on the microarchitecture of carbonate apatite granules fabricated through a dissolution-precipitation reaction

Both the composition and architecture of artificial bone govern bone regeneration. Herein, carbonate apatite (CAp), which has a similar mineral composition to bone, was prepared by immersing calcium carbonate (CaCO3) in a phosphate solution with varying acidification levels (pH 6.0) to pH 8.9, to reveal the influence of pH on the composition and architecture of the resultant CAp granules. The composition, crystal morphology, and architecture of resultant CAp granules was well-characterized by X-ray diffraction, scanning electron microscopy, mercury intrusion porosimetry and so on. Consequently, the rate of compositional transformation from CaCO3 to CAp was much higher at pH 6.0 and pH 7.0 than pH 8.0 and pH 8.9. The pH of the phosphate solution did not affect the macroarchitecture of the resultant CAp granules. In contrast, the composition, crystal morphology, microarchitecture, and degradation behavior of the resultant CAp granules were affected by pH of the phosphate solution. In particular, the open-pore distributions and volumes of the CAp granules prepared at pH 6.0-8.9 were changed to reflect the microarchitecture of the samples. Therefore, this study revealed that the pH-controlled elution precipitation reaction is useful for controlling the composition, crystal morphology, microarchitecture, and degradation behavior of the resultant CAp, while preserving its macroarchitecture. Our findings provide fundamental insights into the design of artificial bones for bone regeneration.

Regulatory cellular and molecular networks in the bone microenvironment during aging

Age-induced abnormalities in bone metabolism disrupt the equilibrium between bone resorption and formation. This largely stems from disturbances in bone homeostasis, in which signaling pathways exert a significant regulatory influence. Aging compromises the functionality of the bone marrow mesenchymal stem cells (BMSCs), ultimately resulting in tissue dysfunction and pathological aging. Age-related bone degradation primarily manifests as reduced bone formation and the increased accumulation of bone marrow fat. Cellular senescence diminishes bone cell vitality, thereby disrupting the balance of bone remodeling. Intensive osteoclast differentiation leads to the generation of more osteoclasts and increased bone resorption. This review provides insight into the impact of aging on bone, encompassing bone cell states during the aging process and bone signaling pathway transformations. It primarily delves into aging-related signaling pathways, such as the bone morphogenetic protein/Smad, Wnt/β-catenin, osteoprotegerin/receptor activator of NF-κB ligand/receptor activator of NF-κB, connexin43/miR21, and nuclear factor erythroid 2-related factor 2/antioxidant response element pathways, seeking to enhance our comprehension of crucial bone cells and their secretory phenotypes during aging. Furthermore, the precise molecular regulatory mechanisms underlying the interactions between bone signaling pathways and aging are investigated.

Mineralized collagen scaffolds for regenerative engineering applications

Collagen is a primary constituent of the tissue extracellular matrix. As a result, collagen has been a common component of tissue engineering biomaterials, including those to promote bone regeneration or to investigate cell-material interactions in the context of bone homeostasis or disease. This review summarizes key considerations regarding current state-of-the-art design and use of collagen biomaterials for these applications. We also describe strategic opportunities for collagen biomaterials to address a new era of challenges, including immunomodulation and appropriate consideration of sex and other patient characteristics in biomaterial design.

Chronic Excess Iodine Intake Inhibits Bone Reconstruction Leading to Osteoporosis in Rats

BACKGROUND

Although iodine modulates bone metabolism in the treatment of thyroid disease, the effect of iodine intake on bone metabolism remains less known.

OBJECTIVE

This study evaluated the effect of excess iodine intake in rats on bone reconstruction in the 6th and 12th month of intervention.

METHOD

Rats were treated with different doses of iodinated water: the normal group (NI, 6.15 μg/d), 5-fold high iodine group (5HI, 30.75 μg/d), 10-fold high iodine group (10HI, 61.5 μg/d), 50-fold high iodine group (50HI, 307.5 μg/d), and 100-fold high iodine group (100HI, 615 μg/d). Thyroid hormone concentrations were determined by a chemiluminescent immunoassay. Morphometry and microstructure of bone trabecula were observed by hematoxylin and eosin staining and microcomputed tomography, respectively. Alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) staining were performed to evaluate the activity of osteoblasts and osteoclasts, respectively.

RESULTS

The 24-h urine iodine concentration increased with iodine intake. The rats in the HI groups had higher serum thyroid-stimulating hormone and decreased serum free thyroxine concentrations in the 12th month than the NI group (all P < 0.05). The percentage of the trabecular bone area and osteoblast perimeter in the 100HI group were significantly lower than those in the NI group (P < 0.05). Increased structure model index was observed in the 50HI and 100HI groups compared with the NI group in the 6th month and increased trabecular separation in the 12th month (all P < 0.05). ALP and TRAP staining revealed osteoblastic bone formation was reduced, and the number of TRAP+ multinucleated cells decreased with increasing iodine intake.

CONCLUSIONS

Excess iodine intake may increase the risk of hypothyroidism in rats. Chronic excess iodine intake can lead to abnormal changes in skeletal structure, resulting in reduced activity of osteoblasts and osteoclasts, which inhibits the process of bone reconstruction and may lead to osteoporosis.

Active osseointegration in an ex vivo porcine bone model

Achieving osseointegration is a fundamental requirement for many orthopaedic, oral, and craniofacial implants. Osseointegration typically takes three to 6 months, during which time implants are at risk of loosening. The aim of this study was to investigate whether osseointegration could be actively enhanced by delivering controllable electromechanical stimuli to the periprosthetic bone. First, the osteoconductivity of the implant surface was confirmed using an in vitro culture with murine preosteoblasts. The effects of active treatment on osseointegration were then investigated in a 21-day ex vivo model with freshly harvested cancellous bone cylinders (n = 24; Ø10 mm × 5 mm) from distal porcine femora, with comparisons to specimens treated by a distant ultrasound source and static controls. Cell viability, proliferation and distribution was evident throughout culture. Superior ongrowth of tissue onto the titanium discs during culture was observed in the actively stimulated specimens, with evidence of ten-times increased mineralisation after 7 and 14 days of culture (p < 0.05) and 2.5 times increased expression of osteopontin (p < 0.005), an adhesive protein, at 21 days. Moreover, histological analyses revealed increased bone remodelling at the implant-bone interface in the actively stimulated specimens compared to the passive controls. Active osseointegration is an exciting new approach for accelerating bone growth into and around implants.

Treatment with PB125® Increases Femoral Long Bone Strength in 15-Month-Old Female Hartley Guinea Pigs

Nuclear factor-erythroid 2-related factor-2 (Nrf2) is a transcription factor that serves as a master regulator of anti-inflammatory agents, phase I xenobiotic, and phase II antioxidant enzymes, all of which provide a cytoprotective role during disease progression. We hypothesized that oral administration of a purported phytochemical Nrf2-activator, PB125®, would increase long bone strength in aging Hartley guinea pigs, a model prone to musculoskeletal decline. Male (N = 56) and female (N = 56) guinea pigs were randomly assigned to receive daily oral treatment with either PB125® or vehicle control. Animals were treated for a consecutive 3-months (starting at 2-months of age) or 10-months (starting at 5-months of age) and sacrificed at 5-months or 15-months of age, respectively. Outcome measures included: (1) ANY-maze™ enclosure monitoring, (2) quantitative microcomputed tomography, and (3) biomechanical testing. Treatment with PB125® for 10 months resulted in increased long bone strength as determined by ultimate bending stress in female Hartley guinea pigs. In control groups, increasing age resulted in significant effects on geometric and structural properties of long bones, as well as a trending increase in ultimate bending stress. Furthermore, both age and sex had a significant effect on the geometric properties of both cortical and trabecular bone. Collectively, this work suggests that this nutraceutical may serve as a promising target and preventive measure in managing the decline in bone mass and quality documented in aging patients. Auxiliary to this main goal, this work also capitalized upon 5 and 15-month-old male and female animals in the control group to characterize age- and sex-specific differences on long bone geometric, structural, and material properties in this animal model.

Combined musculoskeletal finite element modeling of femur stress during reactive balance training

The purpose of this study was to determine the material stresses experienced in the femoral neck during the stepping phase of recovery from a forward loss of balance achieved both using release from a static forward lean and rapid treadmill accelerations in 8 older adults. A scalable musculoskeletal model with 23 degrees of freedom and 92 force actuators was used to calculate joint reaction forces. A finite element model of the femur used joint reaction forces calculated by the musculoskeletal model to calculate the material stresses during stepping. Balance recovery from a static forward lean angle had a greater joint contact force and greater maximum tensile stress than a recovery from treadmill induced perturbations both before and after a training session. Hip joint contact loads were found to be large in magnitude, however, all stresses experienced by the bone are less than critical yield stresses for trabecular bone. We suggest that stepping balance recovery is safe for older adults with no obvious loss of bone density or strength and that analyses such as finite element analysis are necessary to understand stresses in the material at the joint level.

Recombinant bone matrix maintains the graft space, induces vascularized bone regeneration and preserves canine tooth extraction socket structure

AIM

Recombinant bone matrix (RBM) is a newly conceived and engineered porous bone graft granule of average size 600 μm composed of purified recombinant collagen peptide. We sought to examine the behaviour with time of RBM that was grafted in the canine tooth extraction socket.

MATERIALS AND METHODS

The canine tooth extraction socket of the hemisectioned mandibular third premolar distal root was grafted with RBM granules, whereas the opposite side extraction socket served as non-grafted control. The mandibular samples were harvested at 1, 3 and 6 months of healing and subjected to micro-CT imaging and decalcified paraffin-embedded histology. Separately, the effect of RBM was compared with that of deproteinized cancellous bovine bone (DCBB) and bovine atelocollagen plug (BACP) in the canine tooth extraction model at 3 months of healing.

RESULTS

RBM maintained the grafted space in the socket and the gingival connective tissue until new bone was formed within its porous space. The regenerated bone was highly vascularized and continued to mature, while RBM was completely bioresorbed by 6 months. The buccal and lingual alveolar ridge heights of the RBM-grafted extraction socket was better preserved than those of non-grafted control sockets. The degree of socket preservation by RBM was equivalent to that by DCBB, although their healing mechanisms were different.

CONCLUSIONS

This study demonstrated that RBM induced controlled active bone regeneration and preserved the extraction socket structure in a canine model. Bioresorbable RBM engineered without animal or human source materials presents a novel bone graft category with robust bone regenerative property.

Open vs Closed Management of Condylar Fracture Our Experience of 100 Cases in a Suburban Tertiary Care Hospital

Study Design

Retrospective Observational Study.

Objective

Mandibular condyle fractures are distinctive among maxillofacial injuries in which they disrupt mandibular function in a way that other traumatic injuries do not. Condylar fractures can be treated using either the conservative (closed reduction and immobilisation) or surgical (open reduction and internal fixation) approaches. Both of these modalities of treatment have advantages and disadvantages, as well as indications and contraindications. The purpose of this study is to compile and compare our experience in the management of condylar fractures through open and closed reduction.

Methods

The present retrospective analysis included a total 100 patients of condylar fractures in patients > 18 years of age who were randomly divided into nonsurgical and surgical group based on Edward Ellies criteria. In the present study, the outcomes of conservative vs surgical management of condylar fractures were discussed in terms of seven parameters, including the maximal inter-incisal mouth opening, protrusive and lateral excursive movements of the mandible, status of occlusion, deviation of mandible during mouth opening, temporo-mandibular disorders and facial nerve paralysis which were measured and evaluated pre- and post-operatively at different intervals of time. Follow-up period was for 6 months.

Results

It was noted that the main cause of condylar fracture was trauma with a male predilection with an average age of 32.6 ± 1.2 years. Subcondylar fracture was the commonest type of condylar fracture that we encountered. 33.3% of the patients had restricted mouth opening and 57% of the patients had deranged occlusion. 37% of the patients were treated surgically and 48.6% of these fractures were approached using peri-angular approach. More patients had an increased mouth opening and a stable occlusion at the 6 months follow-up when compared to that of the 2 month follow up.

Conclusions

From the above study we can conclude that the treatment plan should be patient specific and follow the algorithm for a particular type of fracture. We endorse the same based on our experience in treating condylar fractures over the last 5 years. The art of decision making solely depends on the surgeon's expertise in managing condylar fractures.

Age estimation from alveolar bone loss, re-evaluation of Ruquet's method

There are many dental age estimation methods, but all the methods do not correspond, especially for aging methods for adults and mature individuals, to the reality of the forensic field, which favors simple, effective, and easy-to-use methods. Ruquet (2015) developed a method based on alveolar bone loss that predicts age for individuals between 25 and 60 years old and is even more accurate for those 25-40 years old. This study re-evaluated Ruquet's alveolar bone loss method using three-dimensional imaging of individuals whose age and sex were known, without taking into account their medical conditions. Digital measurements, from the cemento-enamel junction (CEJ) to the alveolar bone crest (ABC), were performed on the mesial and distal surfaces of teeth on 243 patients, independent of the tridimensional imaging test. With these measurements, two alveolar bone loss averages (ABL) were calculated, one with all the teeth present on the arches and another with only Ramfjörd's teeth. Bone loss showed a significant correlation with age (p < 0.001). The age estimation with all teeth and with only Ramfjörd's teeth showed a statistically significant difference, and age estimation was more accurate when all teeth were used. The assessment of alveolar resorption appears to be an interesting tool for age estimation in adult individuals. However, the method still lacks precision, and the mean absolute errors (MAEs) obtained by age group were all greater than 5 years, except for the age group 35-39 years old, for the age estimation with all teeth. Further studies should explore this existing correlation between alveolar bone loss and age and refine this method to make it more accurate.