Bone Recovery Research Articles

Pig and dog use in the pre‐contact Society Island Chiefdoms: integrated ethnohistoric, archaeological and use‐web analyses

ABSTRACTPig and dog were highly valued animals in pre‐contact Polynesia. In this paper, I focus on pig and dog use in the resource rich, and hierarchically complex, pre‐contact Society Island chiefdoms. Utilizing ethnohistoric data and human‐centred use‐webs data, I provide a preliminary study of the diverse ways that pigs and dogs were used in pre‐contact Mā‘ohi life across 13 use categories. Ethnohistoric analyses indicate that pigs, and to some extent dogs, were intimately associated with elite ceremonial use, yet pigs were commonly associated with war and fertility rituals, while dogs were commonly associated with peacekeeping events. Preliminary comparison of pig and dog frequencies at eight excavated archaeological sites suggests pig bones far outnumber dog bones. There is also differential recovery of pig and dog bone in terms of site function and site status, with high status temples dating to the Centralization Phase having the highest incidence of both species. It is highly likely that the advent of the ‘Oro war cult led to intensified pig husbandry, given this animal's robust associations with ritual use, moral notions of chiefly power and cosmology. Why dog husbandry was less intensified in the Society Islands, and why this animal was perhaps accessed largely through long‐distance trade relationships, is an ongoing question.

The Importance of bone health for pediatric Athletes: from Juvenile Osteochondral Injury to Relative Energy Deficiency in Sports

Vitamin D is pivotal for bone health, muscle strength, recovery, and overall athletic performance. This article discusses the effects of Vitamin D deficiency among athletes, with a specific focus on its connection to sports-related conditions like Relative Energy Deficiency in Sport (RED-S) and Juvenile Osteochondritis Dissecans (JOCD). Additionally, we review the importance of vitamin D for muscle strength and muscle repair. Vitamin D deficiency exacerbates the risk of stress fractures in RED-S patients due to its impact on bone biology. Research points to an increased incidence of vitamin D deficiency in JOCD patients, indicating a potential connection between the condition and low Vitamin D levels. Children and athletes should be screened for vitamin D deficiency as supplementation has been found to have positive outcomes. This article underscores the pivotal role of Vitamin D in athletic performance. Further research is essential to elucidate how Vitamin D deficiency contributes to sports-related pathologies and to establish the optimal Vitamin D levels for injury prevention in athletes.

Bone health and the masters runner.

Masters runners are often defined as those ages 35 years and older who train and compete in running events. These runners represent a growing population of the overall running community and experience running-related injuries including bone stress injuries (BSIs). Similar to younger runners, health considerations in masters runners include the goal to optimize bone health with focus on mitigating age-associated loss of bone strength and preventing BSIs through a combination of ensuring appropriate physical activity, optimizing nutrition, and correcting faulty biomechanics. Importantly, BSIs in masters runners may include characteristics of both overuse injury from insufficient recovery and failure of bone weakened by age-related loss of bone (insufficiency fractures). This narrative review covers the limited available research on strategies to optimize bone health in masters runners. Applying knowledge on masters athletes and extrapolating from other populations, we propose strategies on treatment and prevention of BSIs. Finally, the review highlights gaps in knowledge that require further age-specific discoveries to advance treatment and prevention.

Naringenin roled octacalcium phosphate reinforced with polyvinyl alcohol composite for sarcoma affected bone repair.

Osteosarcoma is a rare cancer affecting disease for children and young adults; complete healing from this condition is quite difficult. Recently, new regeneration materials have been preferred, including natural compound companied implants for affected bone repair, and it is effectively used to treat osteosarcoma disease. Hence, Octa calcium phosphate (OCP) reinforced with poly (vinyl alcohol) (PVA) and oleic acid (OA) with Naringenin (NRG) composite was prepared and studied to cure the sarcoma affected bone. The physicochemical nature of the prepared OCP, PVA/OA/OCP, and PVA/OA/OCP/NRG composite were characterized by FT-IR, SEM, and XRD techniques. The in vitro release of the NRG from the PVA/OA/OCP/NRG composite was evaluated by UV-visible spectroscopy and the NRG release rate was observed at 98.0 % over 24 h. Biocompatibility and cell viability of the prepared OCP, PVA/OA/OCP, and PVA/OA/OCP/NRG composite are investigated in adipose-derived stem cells (ASCs) on different days. Interestingly, the PVA/OCP/OA/NRG composite shows an increase of 74.0 % to 92.0 % in cell survival, indicating that the composite is biocompatible. Similarly, the ability of NRG in the composite is to suppress cancer cells and it was determined in lung cancer (A549) cells. NRG-loaded PVA/OCP/OA/NRG shows good inhibition ability, nearly 43 % at 72 h. From the results, the prepared composite materials can inhibit cancer cells and be viable in stem cell growth. Since the materials will serve as potential regenerative materials for sarcoma-affected bone recovery.

Initial Upper Palaeolithic material culture by 45,000 years ago at Shiyu in northern China.

The geographic expansion of Homo sapiens populations into southeastern Europe occurred by ∼47,000 years ago (∼47 ka), marked by Initial Upper Palaeolithic (IUP) technology. H. sapiens was present in western Siberia by ∼45 ka, and IUP industries indicate early entries by ∼50 ka in the Russian Altai and 46-45 ka in northern Mongolia. H. sapiens was in northeastern Asia by ∼40 ka, with a single IUP site in China dating to 43-41 ka. Here we describe an IUP assemblage from Shiyu in northern China, dating to ∼45 ka. Shiyu contains a stone tool assemblage produced by Levallois and Volumetric Blade Reduction methods, the long-distance transfer of obsidian from sources in China and the Russian Far East (800-1,000 km away), increased hunting skills denoted by the selective culling of adult equids and the recovery of tanged and hafted projectile points with evidence of impact fractures, and the presence of a worked bone tool and a shaped graphite disc. Shiyu exhibits a set of advanced cultural behaviours, and together with the recovery of a now-lost human cranial bone, the record supports an expansion of H. sapiens into eastern Asia by about 45 ka.

Calcitonin gene-related peptide regulates periodontal tissue regeneration

Calcitonin gene-related peptide (CGRP), a neuropeptide composed of 37 amino acids secreted from the sensory nerve endings, reportedly possesses various physiological effects, such as vasodilation and neurotransmission. Recently, there have been increasing reports of the involvement of CGRP in bone metabolism; however, its specific role in the pathogenesis of periodontitis, particularly in the repair and healing processes, remains to be elucidated. Therefore, this study aimed to investigate dynamic expression patterns of CGRP during the destruction and regeneration processes of periodontal tissues in a mouse model of experimental periodontitis. We also explored the effects of CGRP on periodontal ligament cells, which can differentiate to hard tissue-forming cells (cementoblasts or osteoblasts). Our findings demonstrated that CGRP stimulation promotes the differentiation of periodontal ligament cells into hard tissue-forming cells. Experimental results using a ligature-induced periodontitis mouse model also suggested fluctuations in CGRP expression during periodontal tissue healing, underscoring the vital role of CGRP signaling in alveolar bone recovery. The study results highlight the important role of nerves in the periodontal ligament not only in sensory reception in the periphery, as previously known, but also in periodontal tissue homeostasis and tissue repair processes.

Rat bone responses to hindlimb unloading-reloading: Composition, BMD and mechanical properties

IntroductionBone loss in lower limbs under space microgravity condition can persist even after the astronauts return to Earth's gravitational environment. It is crucial to determine the extent and timing of bone recovery after spaceflight, especially for long-term flights. However, there is a lack of comprehensive descriptions of the recovery of various aspects of bone quality, particularly in terms of compositional characteristics that reflect changes in bone quality. Therefore, the objective of this study is to investigate the alterations in bone mineral density, composition characteristics, and mechanical properties of rat lower limbs during unloading (tail suspension) and the subsequent recovery loading period. MethodsRats were subjected to tail suspension for four weeks (TS4) followed by reloading for an additional four weeks. Bone mineral density (BMD) was measured by μ-CT and analyzed. The mechanical properties of the tibia were assessed by a three-point bending test, and the composition characteristics of bone tissue were evaluated using Raman spectroscopy. Regression analysis was performed to identify main component related to mechanical property. ResultsIn the metaphysis, BMD of the tibia significant decreased, particularly in trabecular bone. Upon reloading, only the cortical bone showed recovery. In the diaphysis, cortical bone remained unchanged during unloading but demonstrated delayed bone loss during the reloading period. Simultaneously, the mechanical properties of tibia experienced a substantial reduction after four weeks of unloading, The stiffness and maximum strength did not fully recover, though the elastic modulus and the ultimate strength were restored following the reloading process. Raman spectroscopy characterization found an increase in the carbonate substitution and crystal crystallinity of the diaphysis after 4 weeks of unloading. There was an intriguing alteration in the mineralized collagen ratio, that an increase was observed in the diaphysis while a decrease was observed in the metaphysis. During 4 weeks of reloading, the compositional characteristics of the diaphysis recovered earlier than those of the metaphysis, with the exception of crystallinity which remained unrecovered. Regression analysis indicated that carbonate replacement has a strong correlation to bone mechanical properties during the 4 weeks of unloading and subsequent 4 weeks of reloading. ConclusionsThe data obtained in this study highlight the incomplete recovery of bone mineral density, mechanical properties, and compositional characteristics during reloading in tail-suspended rats. These findings deepen our understanding of microgravity-induced bone loss and provide valuable information to develop interventions not only for astronauts but also for persons on earth during and after prolonged periods of unloading.

Novel waste bone recovery system for CO2 and SOx utilization in cement plants using microbubble carbonation reactor

Cement has been widely used as a primary building material to construct various types of infrastructure. However, cement plants emit excessive carbon dioxide (CO2) and sulfur oxide (SOx) during calcination of limestone. Animal bone residues can reduce air pollutants as they contain calcium hydroxyapatite (Ca10(PO4)6(OH)2), which can capture and utilize CO2 and SOx. Therefore, brushite cement (CaHPO4∙2 H2O) and raw materials of cement, such as calcium carbonate (CaCO3) and calcium sulfate (CaSO4), can be recovered. In this study, a novel waste bone recovery system for CO2 and SOx utilization using cement plant flue gas was developed using a microbubble carbonation reactor (MCR). The system was designed using a process simulation model with the experimental results of the proposed MCR. Using an MCR with a high carbonation rate increases economic feasibility by decreasing the capacity of the conventional cost-intensive carbonation process. The proposed model involves the following steps: (1) waste bone dissolution and synthesis of CaHPO4∙2 H2O; (2) SOx capture and utilization; (3) CO2 capture and utilization using MCR. The total annualized cost (TAC) was determined to validate the economic feasibility of the system. Consequently, 99% of SOx and 94% of CO2 were captured using the production of CaSO4 and CaCO3 at the MCR, respectively. Additionally, the TAC of the proposed system can be decreased by 44% and 27% compared to the base cases 1 and 2 corresponding to the conventional SOx and CO2 capture processes.

Metabolomics provides insights into acceleration of bone healing in fractured patients with traumatic brain injuries.

While clinical surveys have frequently reported that patients with traumatic brain injuries (TBIs) and comorbidities experience faster healing, the underlying mechanisms have been investigated but remain unclear. As a comprehensive comparison and analysis of the metabolic characteristics of these two pathologies have not been undertaken, we developed a rat model of fracture and TBI and collected serum samples for metabolomic analysis using ultra-high performance liquid chromatography-quadrupole time-of-flight MS (UHPLC-Q-TOF/MS). In total, we identified 40 differential metabolites and uncovered related pathways and potential mechanisms, including aminoacyl-transfer RNA biosynthesis; differential amino acids such as leucine, cholylhistidine, aspartyl-lysine; and related lipid metabolism, and discussed their impacts on bone formation in detail. This study highlights that the UHPLC-Q-TOF/MS-based metabolomics approach offers a better understanding of the metabolic links between TBI and accelerated bone recovery.

Spontaneous recovery of underlying bony erosion following surgical removal of craniofacial dermoid cysts in periatric patients: A prospective study

This study aimed to evaluate the spontaneous recovery of bone deformity after surgical excision of craniofacial dermoid cysts in pediatrics.Pediatric patients who underwent excision of a dermoid cyst were included in the study. A prospective analysis was conducted to evaluate the amount of bone recovery by comparing the depth of bony concavity in the preoperative and postoperative (6 months) ultrasonography.In 145 of 187 patients with preoperative imaging available, the mean size of dermoid cysts was 1.4 cm3 (range, 0.1 to 9.5), and 41.4% (60/145 cases) showed cranial bone depression. In the comparison of preoperative and postoperative ultrasonography of 30 patients, the mean depth of bony cavity decreased significantly from 4.0 to 0.9 mm (p<0.001) after a mean of 6.7 months postoperatively. There was 13.3% (4/30) of mild (≤2.0 mm), 40.0% (12/30) of moderate (>2.0 to ≤4.0 mm), and 46.7% (14/30) of severe (>4.0 mm) depression, and the concavity depth significantly decreased in all groups (p = 0.028, mild; p<0.001, moderate; p<0.001 severe).Within the limitations of the study it seems that significant recovery of cranial bone depression does take place within 6 months after excision of craniofacial dermoid cysts in pediatric patients, saving the need for immediate reconstruction.

Influence of Low-Intensity Pulsed Ultrasound Parameters on the Bone Mineral Density in Rat Model: A Systematic Review.

Bone recovery typically depends on the age of organisms or the prevalence of metabolic disorders such as osteoporosis, which is a metabolic condition characterized by decreased bone strength and bone mineral density (BMD). Therefore, low-intensity pulsed ultrasound (LIPUS), a non-invasive method for osteogenic stimulation, presents promising results. However, heterogeneity in animal study designs is a typical characteristic. Hence, we conducted a systematic review to evaluate the effectiveness of LIPUS in the recovery of experimental bone defects using rat models. We examined the areal and volumetric BMD to identify LIPUS doses to be applied and evaluated the accuracy reported by previous studies. The Virtual Health Library regional portal, PubMed, Embase, EBSCOhost, Scopus and CAPES were reviewed for animal studies that compared fracture treatments based on LIPUS with sham or no treatments using rat models and reported BMD as an outcome. The tool provided by the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) and the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES) checklist were used to assess the bias and quality of such studies. Of the six studies reviewed, the most frequently used LIPUS dose had an ultrasonic frequency of 1.0MHz, repetition rate of 0.1kHz and pulse duration of 2000μs. An intensity (ISATA) of 30mW/cm2 was the most preferred for bone recovery. However, the BMD could not solely irrefutably evaluate the effectiveness of LIPUS in bone recovery as the results were discordant with each other. The discrepancies in experimental methodologies, low-quality classifications and high risk of bias in the selected studies, however, did not validate the undertaking of a meta-analysis. On the basis of the BMD results, no sufficient evidence was found to recommend the use of LIPUS for bone recovery in rat models. Thus, this systematic review indicates that the accuracy of such reports must be improved to improve their scientific quality to facilitate a transition of LIPUS applications from pre-clinical research to clinic use.

Comparison of Postoperative Bone Healing in Patients With Unilateral Biportal Endoscopic Lumbar Discectomy and Microscopic Lumbar Discectomy

Objective: Unilateral biportal endoscopic lumbar discectomy and microscopic lumbar discectomy are typical surgical treatments for spinal disease that are performed in different environment. This study investigated differences in bone healing at the postoperative laminecrtomy site between 2 surgical treatments performed in different environments.Methods: From January 2018 to June 2021, 66 patients who underwent laminectomy at Department of Neurosurgery, Gangnam Severance Hospital were retrospectively reviewed. All patients were matched for sex, age, body mass index, bone mineral density, and follow-up duration at a 1:2 matching ratio and were divided into the UBE group (22 patients) and the microscopic discectomy group (44 patients). We investigated the site of laminectomy shown on preoperative and postoperative x-ray images using ImageJ software. The factors related to bone healing were also investigated.Results: The average bone healing area was 69.59 mm&lt;sup&gt;2&lt;/sup&gt; in the UBE group and 44.56 mm&lt;sup&gt;2&lt;/sup&gt; in the microscopic discectomy group, constituting a significant difference (p = 0.022). The remaining laminectomy area was significantly lower in the UBE group than in the microscopic discectomy group (13.91 mm&lt;sup&gt;2&lt;/sup&gt; vs. 53.84 mm&lt;sup&gt;2&lt;/sup&gt;, p &lt; 0.001). The bone recovery ratio in the UBE group was 85.42%, compared to 51.33% in the microscopic discectomy group, which was a significant difference (p &lt; 0.001). The primary laminectomy area, bone healing during 6 months, and clinical outcomes were not significantly different between the 2 groups.Conclusion: Compared with the microscopic discectomy group, the UBE group had a larger bone healing area and a higher bone recovery ratio for patients with lumbar discectomy. These findings suggest that preserving normal structures is more feasible during UBE than during microscopic surgery.

Reambulation following hindlimb unloading attenuates disuse-induced changes in murine fracture healing.

Patients with bone and muscle loss from prolonged disuse have higher risk of falls and subsequent fragility fractures. In addition, fracture patients with continued disuse and/or delayed physical rehabilitation have worse clinical outcomes compared to individuals with immediate weight-bearing activity following diaphyseal fracture. However, the effects of prior disuse followed by physical reambulation on fracture healing cellular processes and adjacent bone and skeletal muscle recovery post-injury remains poorly defined. To bridge this knowledge gap and inform future treatment and rehabilitation strategies for fractures, a preclinical model of fracture healing with a history of prior unloading with and without reambulation was employed. First, skeletally mature male and female C57BL/6J mice (18 weeks) underwent hindlimb unloading by tail suspension (HLU) for 3 weeks to induce significant bone and muscle loss modeling enhanced bone fragility. Next, mice had their right femur fractured by open surgical dissection (stabilized with 24-gauge pin). The, mice were randomly assigned to continued HLU or allowed normal weight-bearing reambulation (HLU + R). Mice given normal cage activity throughout the experiment served as healthy age-matched controls. All mice were sacrificed 4-days (DPF4) or 14-days (DPF14) following fracture to assess healing and uninjured hindlimb musculoskeletal properties (6-10 mice per treatment/biological sex). We found that continued disuse following fracture lead to severely diminished uninjured hindlimb skeletal muscle mass (gastrocnemius and soleus) and femoral bone volume adjacent to the fracture site compared to healthy age-matched controls across mouse sexes. Furthermore, HLU led to significantly decreased periosteal expansion (DPF4) and osteochondral tissue formation by DPF14, and trends in increased osteoclastogenesis (DPF14) and decreased woven bone vascular area (DPF14). In contrast, immediate reambulation for 2 weeks after fracture, even following a period of prolonged disuse, was able to increase hindlimb skeletal tissue mass and increase osteochondral tissue formation, albeit not to healthy control levels, in both mouse sexes. Furthermore, reambulation attenuated osteoclast formation seen in woven bone tissue undergoing disuse. Our results suggest that weight-bearing skeletal loading in both sexes immediately following fracture may improve callus healing and prevent further fall risk by stimulating skeletal muscle anabolism and decreasing callus resorption compared to minimal or delayed rehabilitation regimens.

Evaluating the Effect of Jointly Administering Synthetic Graft and Ankaferd Blood Stopper for Bone Recovery in Created Bone Deformities in Diabetic Rats

Objective: In the present paper, it was purposed to examine the late impacts of bone tissue recoveries in combination with synthetic grafts and Ankaferd Blood Stopper (ABS), which are effective in bone wound healing in diabetic rats.&#x0D; Methods: A total of 64 Wistar albino male rats with diabetes were studied. A bone deformity was generated in the calvarium of diabetic rats. These diabetic rats are divided into 4 different groups. Only saline was applied to the bone defect in group 1, Beta-tricalcium phosphate (β-TCP) graft was administered to Group 2, ABS solution to Group 3, (β-TCP+ABS) were administered to group 4. Eight rats from each group were sacrificed on the 28th day and another 8 rats on the 56th day. Immunohistochemical, histopathological, and Dual Energy X-ray Absorptiometry (DEXA) analyzes of the obtained samples were made.&#x0D; Results: In histopathological measurements, osteoblastic activity and bone regeneration were considerably higher in the group treated with group 2 and group 4 when compared to the control group on the 28th and 56th day (p˂ .05). Western blotting findings showed that the osteopontin (OP) and osteonectin (ON) expression at 28th day increased dramatically in the treated with group 4. DEXA analyzes revealed that BMC values in groups treated with group 2, group 3 and group 4 on 28th day were considerably higher than the control group (p˂ .05).&#x0D; Conclusion: We can believe and conclude that ABS in combination with a β-TCP bone graft will produce more successful outcomes on wound&#x0D; healing and formation of new bone in diabetic rats.

Synergistic effect of drug/antibiotic-impregnated micro/nanohybrid mesoporous bioactive glass/calcium phosphate composite bone cement on antibacterial and osteoconductive activities

Calcium phosphate bone cements (CPC) can be used in minimally invasive surgery because of their injectability, and they can also be used to repair small and irregular bone defects. This study aimed to release the antibiotic gentamicin sulfate (Genta) to reduce tissue inflammation and prevent infection in the early stages of bone recovery. Subsequently, the sustained release of the bone-promoting drug ferulic acid (FA) mimicked the response of osteoprogenitor D1 cells interaction, thereby accelerating the healing process of the overall bone repair. Accordingly, the different particle properties of micro-nano hybrid mesoporous bioactive glass (MBG), namely, micro-sized MBG (mMBG) and nano-sized MBG (nMBG), were explored separately to generate different dose releases in MBG/CPC composite bone cement. Results show that nMBG had better sustained-release ability than mMBG when impregnated with the same dose. When 10 wt% of mMBG hybrid nMBG and composite CPC were used, the amount of MBG slightly shortened the working/setting time and lowered the strength but did not hinder the biocompatibility, injectability, anti-disintegration, and phase transformation of the composite bone cement. Furthermore, compared with 2.5wt%Genta@mMBG/7.5 wt% FA@nMBG/CPC, 5wt.%Genta@mMBG/5wt.%FA@nMBG/CPC exhibited better antibacterial activity, better compressive strength, stronger mineralization of osteoprogenitor cell, and similar 14-day slow-release trend of FA. The MBG/CPC composite bone cement developed can be used in clinical surgery to achieve the synergistic sustained release of antibacterial and osteoconductive activities.

Role of myofascia in the recovery of bone loss after reloading in tail-suspended rats

Astronauts experience severe musculoskeletal degradation in space. After returning to earth, bone loss recovery did not parallel muscle recovery. Fascia may play an important role as a considerable part of muscle force is transmitted to bone through fascia. However, little is known about how fascia changes in microgravity and its effect on the development of musculoskeletal degeneration. In this study, a rat hindlimb unloading model was used to simulate microgravity (21 days of tail suspension) and then reloading for 7 days, 14 days and 21 days. After different periods, bone mineral density (BMD) and microstructure of the tibia were analyzed by μCT, the mechanical properties of the tibia were determined by the three-point bending test and the mechanical properties of fascia were explored by tensile test. The results show that, after tail suspension, collagen Ⅰ in myofascia was significantly increased (p < 0.05), the myofascial elastic modulus was significantly decreased (p < 0.05), BMD of the tibia was significantly decreased (p < 0.05) and the microstructure of the tibia had deteriorated. After 21 days of reloading, there was no significant improvement in the myofascial elastic modulus as well as in the tibial maximum load. Correlation analysis results showed that the myofascial elastic modulus was significantly correlated with the tibial maximum load. In summary, the deterioration of mechanical property of myofascia induced by tail suspension did not recover when the time of reloading was the same as the time of unloading. This indicates that the delayed bone recovery after being exposed to microgravity was associated with deterioration of myofascia.

Is the association of electrochemotherapy and bone fixation rational in patients with bone metastasis?

Bone metastases are frequent in patients with cancer. Electrochemotherapy (ECT) is a minimally invasive treatment based on a high-voltage electric pulse combined with an anticancer drug. Preclinical and clinical studies supported the use of ECT in patients with metastatic bone disease, demonstrating that it does not damage the mineral structure of the bone and its regenerative capacity, and that is feasible and efficient for the treatment of bone metastases. Year 2014 saw the start of a registry of patients with bone metastases treated with ECT, whose data are recorded in a shared database. (1) Among patients who underwent ECT and internal fixation for bone metastasis, how many experienced a reduction of pain? (2) How many cases showed a radiological response? (3) How many patients presented local or systemic complication after ECT and fixation? Patients were treated in Bologna at Rizzoli Orthopaedic Institute between March 2014 and February 2022 and recorded in the REINBONE registry (a shared database protected by security passwords): clinical and radiological information, ECT session, adverse events, response, quality of life indicators, and duration of follow-up were registered. We consider only cases treated with ECT and intramedullary nail during the same surgical session. Patients included in the analysis were 32: 15 males and 17 females, mean age 65 ± 13 years (median 66, range 38-88 years), mean time since diagnosis of primary tumor 6.2 ± 7.0 years (median 2.9, range 0-22 years). Nail was indicated in 13 cases for a pathological fracture in, 19 for an impending fracture. Follow-up was available for 29 patients, as 2 patients were lost to follow-up and 1 was unable to return to controls. Mean follow-up time was 7.7 ± 6.5 months (median 5, range 1-24), and 16 patients (50%) had a follow-up longer than 6 months. A significant decrease in pain intensity was observed at the mean Visual Numeric Scale after treatment. Bone recovery was observed in 13 patients. The other 16 patients remained without changes, and one presented disease progression. One patient presented a fracture occurrence during the ECT procedure. Among all patients, bone recovery was observed in 13 patients: complete recovery in 1 patient (3%) and partial recovery in 12 patients (41%). The other 16 patients remained without changes, and one presented disease progression. One patient presented a fracture occurrence during the ECT procedure. However, healing was possible with normal fracture callus quality and healing time. No other local or systemic complications were observed. We found that pain levels decreased after treatment in 23 of the 29 cases for a pain relief rate of 79% at final follow-up. Pain is one of the most important indicators of quality of life in patients that undergo palliative treatments. Even if conventional external body radiotherapy is considered a noninvasive treatment, it presents a dose-dependent toxicity. ECT provides a chemical necrosis preserving osteogenic activity and structural integrity of bone trabeculae; this is a crucial difference with other local treatments and allows bone healing in case of pathological fracture. The risk of local progression in our patient population was small, and 44% experienced bone recovery while 53% of the cases remained unchanged. We observe intraoperative fracture in one case. This technique, in selected patients, improves outcome in bone metastatic patients combing both the efficacy of the ECT in the local control of the disease and the mechanical stability with the bone fixation to synergize their benefits. Moreover, the risk of complication is very low. Although encouraging data, comparative studies are required to quantify the real efficacy of the technique. Level of Evidence Level I, therapeutic study.

Could the pulp be preserved in tooth with root resorption caused by embedded tooth?

Background/purposeAt present, there are no recognized guidelines or consensus for the treatment strategy of the asymptomatic tooth with external root resorption caused by an embedded tooth (et-ERR). Most clinicians would like prophylactic or concomitant root canal therapy (RCT) along with the extraction of the embedded tooth. The purpose of this study was to report the prognosis of external root resorption (ERR) and investigate the possibility to preserve the vital pulp of ERR tooth. Materials and methodsThe patients who had asymptomatic et-ERR teeth were included. After extraction of the embedded tooth, the clinical process, prognosis, and adverse events were observed, including symptoms, clinical, and radiographic examination throughout the follow-up period. ResultsA total of four cases with special features were reported. Over a follow-up period of up to 12 months, on clinical examination, 3 ERR teeth preserved pulp vitality without additional intervention except for tooth extraction and have kept normal function free from any symptoms. Radiographic examination showed bone regeneration and recovery of periodontal tissue. While one case failed to keep the vital pulp and ended in intentional replantation. ConclusionAs to et-ERR, if the embedded tooth can be promptly extracted with a minimally invasive technique and effective infection control, the pulp vitality of the et-ERR tooth is likely to be preserved. In this situation, the preferred management of asymptomatic et-ERR tooth is just followed up without prophylactic RCT.

Extracellular vesicles rejuvenate the microenvironmental modulating function of recipient tissue-specific mesenchymal stem cells in osteopenia treatment.

Systemic transplantation of mesenchymal stem cells (MSCs), such as bone marrow MSCs (BMMSCs) and stem cells from human exfoliated deciduous teeth (SHED), is considered a prominent treatment for osteopenia. However, the mechanism of action of the transplanted MSCs has been poorly elucidated. In the recipient target tissue, including bone and bone marrow, only a few donor MSCs can be detected, suggesting that the direct contribution of donor MSCs may not be expected for osteopenia treatment. Meanwhile, secretomes, especially contents within extracellular vesicles (EVs) released from donor MSCs (MSC-EVs), play key roles in the treatment of several diseases. In this context, administrated donor MSC-EVs may affect bone-forming function of recipient cells. In this review, we discuss how MSC-EVs contribute to bone recovery recipient tissue in osteopenia. We also summarize a novel mechanism of action of systemic administration of SHED-derived EVs (SHED-EVs) in osteopenia. We found that reduced telomerase activity in recipient BMMSCs caused the deficiency of microenvironmental modulating function, including bone and bone marrow-like niche formation and immunomodulation in estrogen-deficient osteopenia model mice. Systemic administration of SHED-EVs could exert therapeutic effects on bone reduction via recovering the telomerase activity, leading to the rejuvenation of the microenvironmental modulating function in recipient BMMSCs, as seen in systemic transplantation of SHED. RNase-preconditioned donor SHED-EVs diminished the therapeutic benefits of administrated SHED-EVs in the recipient osteopenia model mice. These facts suggest that MSC-EV therapy targets the recipient BMMSCs to rejuvenate the microenvironmental modulating function via telomerase activity, recovering bone density. We then introduce future challenges to develop the reproducible MSC-EV therapy in osteopenia.

Effect of Multi-Walled Carbon Nanotube on the Microstructure, Physical and Mechanical Properties of ZrO2–CaO/Poly(methyl methacrylate) Biocomposite for Bone Reconstruction Application

After bone implant, short-term complications can lead to a complicated approach to recovery, requiring surgical correction associated with additive risks, such as deep infection and double fracture. The development of synthesized biomaterials for bone replacement or repair, as well as the prevalence of osteoporosis, bone fracture, and bone cancer, is therefore of significant importance. This work aims to demonstrate the effect of adding multi-walled carbon nanotube (MWCNTs) to the (PMMA/ZrO2–CaO) bio-composites to fabricate a new hybrid biocomposite system for bone recovery and replacement applications. Four groups of composite samples were produced PMMA/(0, 5, 10, 15, 20)% weights of ZrO2–CaO and adding (0, .1, 0.25, 0.5, 1)% weights of (MWCNTs) to each group. X-ray powder diffraction (XRD), surface topography by field emission scanning electron microscopy (FE-SEM), and fracture strength tests were performed to evaluate the samples’ properties. A number of the most significant characteristics obtained through XRD exhibited a high degree of homogeneous mixing of the composites. In the examination, smooth peaks were obtained and the homogeneous distribution resulted in phase stability. A FE-SEM analysis demonstrated the presence of fibrous structures following the addition of MWCNTs, indicating that this approach would promote adhesion and healing of the tissue, as well as a fibrous arrangement that mimics that of natural bone. The results also showed improvements in mechanical properties by approximately 57%, 38%, 45%, and 6.5% due to the addition of MWCNTs compared to the version sample. Based on the experimental results, the study highlights the potential of these composites in bone reconstruction applications.