Application of biomaterials in Masquelet technology / 中国组织工程研究

BACKGROUND:The remediation and treatment of bone defects present considerable challenges,with a variety of clinical intervention strategies available.One such approach,the Masquelet technique,has demonstrated high rates of success and reliable outcomes and is currently employed in clinical practice.However,the underlying mechanisms of this technique remain incompletely understood,and certain challenges persist in its clinical application,indicating that this technique is not yet fully mature. OBJECTIVE:To compile and categorize the biomaterials currently employed in research aimed at improving the Masquelet technique,in order to provide insights and references for the further development of this technique. METHODS:A literature search of the China National Knowledge Infrastructure and PubMed databases was conducted,spanning publications from January 2013 to November 2022.The search terms used included"Masquelet technique;induced membrane technique;induced membrane;biomaterial;bone defect"in both Chinese and English.A total of 58 articles meeting the inclusion criteria were reviewed. RESULTS AND CONCLUSION:(1)The emergence and continual development of the Masquelet technique provide a therapeutic strategy for treating bone defects.Some researchers are focusing on developing superior spacer materials,autograft substitutes,and membrane materials that mimic the properties of the induced membrane,to simplify the two-stage procedure,shorten treatment duration,and reduce patient distress.(2)Calcium sulfate,silicone,poly(lactic-co-glycolic acid),and polypropylene can replace polymethylmethacrylate bone cement to form induced membranes in animal experiments or clinical applications,each with their advantages.Contrary to expectations,common materials such as titanium and polyvinyl alcohol sponge cannot replace polymethylmethacrylate bone cement.(3)Autograft substitutes are diverse,with allograft bone,β-tricalcium phosphate,absorbable gelatin sponge,α-calcium sulfate hemihydrate,bioactive glass,titanium,and tantalum demonstrating their ability to reduce the quantity of autologous cancellous bone graft required in the second stage of the procedure.Among them,allograft bone,β-tricalcium phosphate,bioactive glass,titanium and tantalum can replace autogenous bone as grafts,and other materials need to be mixed with autogenous bone,in both clinical and fundamental experiments.(4)Biomimetic-induced membranes,human amnion,human decellularized dermis,polytetrafluoroethylene,and even autogenous cortical bone have been shown to possess properties similar to the induced membrane.(5)Most of the application and research of biomaterials in this technology still exist in the stage of basic research and have not been applied in clinical practice or popularized on a large scale,but the above materials can provide more sufficient theoretical basis and new ideas for the exploration of Masquelet technical mechanism,the improvement of surgical methods and clinical application.

Application of pulsed electromagnetic fields in the treatment of orthopedic diseases / 中国组织工程研究

BACKGROUND:Pulsed electromagnetic field is a non-invasive and non-radiative treatment method.Clinical use of pulsed electromagnetic fields in the treatment of orthopedic diseases has achieved certain results. OBJECTIVE:To review the current clinical application of the pulsed electromagnetic field in the treatment of orthopedic diseases,providing a scientific theoretical basis for the clinical treatment of orthopedic diseases. METHODS:The first author used a computer to search PubMed,CBM,Cochrane Library,CNKI,and WanFang Data for related studies on the pulsed electromagnetic field in the treatment of orthopedic diseases,using the keywords of"pulsed electromagnetic field,orthopedics,osteoarthritis,osteoporosis,bone healing,electromagnetic navigation"in English and Chinese.For the literature related to the same content,recent publications were selected.A total of 69 articles were selected from the search results for review. RESULTS AND CONCLUSION:Pulsed electromagnetic field has a definite curative effect on fracture healing.It can be used in the treatment of osteomyelitis by antibacterial,bactericidal,anti-inflammatory and promoting bone healing,and can inhibit osteoporosis and its progress.In addition,the treatment of early osteoarthritis,femoral head necrosis and postoperative rehabilitation of late joint replacement through various ways can become a treatment for orthopedic diseases.However,the therapeutic mechanism of the pulsed electromagnetic field for a variety of orthopedic diseases is still unclear,and most of the research is still in the primary stage.In the future,it is still necessary to obtain more reliable evidence from high-quality research and clinical trials to provide a more perfect basis for the clinical treatment of orthopedic diseases.

Biomaterials and pore characteristics of tendon tissue engineering scaffolds / 中国组织工程研究

BACKGROUND:With the increasing number of tendon transplantation surgeries for tendon injuries,the demand for tendon tissue engineering scaffolds is increasing.Research has found that good pore size and porosity of implants contribute to tissue healing. OBJECTIVE:To review the types of materials currently published for tendon tissue engineering scaffolds and investigate the correlation between various tendon tissue engineering scaffold materials and pores. METHODS:Articles were retrieved on PubMed,Embase,and Web of Science databases,using keywords"tendon"or"ligament"and"tissue scaffold"as well as"porosity"or"permeability".A total of 84 articles meeting the criteria were included to summarize,discuss and anticipate future development directions. RESULTS AND CONCLUSION:The materials used in the research of tendon tissue engineering are mainly divided into two categories:natural tendon scaffold materials and artificial synthetic tendon scaffold materials.Natural scaffold materials include autologous tendons,allogeneic tendons,and xenogeneic tendons.Autogenous tendons and allogeneic tendons have been used in clinical practice for many years.During the preparation of allogeneic tendons and animal experiments,it was found that the process of acellular disinfection resulted in an increase in the pore size and porosity of both types of tendons,but the specific reasons and mechanisms have not been further studied.There are many types of artificial tendon scaffold materials currently being studied,among which artificial ligament products such as Leeds Keio and LARS(Ligament Advanced Reinforcement System)are still in use in some countries.Other materials have not been promoted in clinical practice due to immature technology and other issues.The pores and porosity of artificial tendon scaffold materials also show different trends due to their different materials and preparation techniques.

Expression and action mechanism of stromal cell-derived factor 1 in tendon-bone healing of rabbit rotator cuff / 中国组织工程研究

BACKGROUND:In recent years,some scholars in the field of tendon bone injury have attached stromal cell-derived factor 1 to tissue engineering scaffolds to promote tendon bone healing,and achieved good results.However,whether stromal cell-derived factor 1 promotes tendon bone healing mechanisms and participates in the repair of natural healing has not yet been defined. OBJECTIVE:To study the expression of stroma-cell derived factor 1 during tendon bone healing after rupture of the whole supraspinatus muscle of the rabbit rotator cuff and its migration effect and optimal in vitro migration promoting concentration on stem cells during tendon bone injury. METHODS:Totally 18 adult New Zealand rabbits were randomly selected to establish rotator cuff injury models,and an additional 3 rabbits were selected as blank controls.At 3,5,7,14,21,and 28 days after modeling,three rabbits were executed separately and the rabbits in the blank group were sacrificed.The tissues of tendon bone junction were taken and stored in a-80℃refrigerator.The expression of stromal cell-derived factor 1 was detected by ELISA at each time point after injury.Mesenchymal stem cells were isolated from the bone marrow of young rabbit femur,cultured,and identified.Transwell assay was performed to verify the migration-promoting effect of stromal cell-derived factor 1 on stem cells and the optimal migration-promoting concentration in vitro.The stem cells cultured to P3 were co-cultured with BrdU and injected into the rabbit ear marginal vein,and immunohistochemical staining was used to verify whether the stem cells migrated to the injury site. RESULTS AND CONCLUSION:(1)Stromal cell-derived factor 1 gene expression was bimodal during rotator cuff tendon bone healing.Stromal cell-derived factor 1 gene expression increased significantly at 3 days post-injury(P<0.01)and then decreased,reaching a minimum at 5 days post-injury.It increased again and reached a peak 14 days after injury(P<0.01)and then decreased.(2)Cell immunohistochemical staining displayed that stem cells labeled with BrdU did migrate to the injury site.(3)The results of the transwell experiment exhibited that 60-80 ng/mL stromal cell-derived factor 1 had the best effect on promoting migration of stem cells,while a concentration of 200 ng/mL inhibited migration.(4)Stromal cell-derived factor 1 is involved in the healing of rotator cuff tendon bone during the inflammatory response phase and the proliferation phase.The mechanism of action may be to promote the migration of stem cells to the injury and their differentiation into various types of cells to promote repair.In addition,the pro-migration effect of stromal cell-derived factor 1 exists at a range of concentrations,beyond which it may act as an inhibitor.

Application of bioelectric effect materials in design of bone tissue engineering scaffolds / 中国组织工程研究

BACKGROUND:Bone has bioelectric effects.However,bone defects can lead to loss of endogenous bioelectricity in bone.The implantation of bone tissue engineering scaffolds with bioelectric effect into bone defects will replenish the missing electrical signals and accelerate the repair of bone defects. OBJECTIVE:To introduce the bioelectric effect of bone tissue and expound the repair effect of electrical stimulation on bone defects,summarize the research progress of bioelectric effect applied to bone tissue engineering,in order to provide new ideas for the research of bone tissue engineering. METHODS:Relevant articles were searched on CNKI,WanFang,PubMed,Web of Science and ScienceDirect databases,using"bioelectrical effect,bioelectrical materials,electrical stimulation,bone tissue engineering,bone scaffold,bone defect,bone repair,osteogenesis"as the English and Chinese search terms.Finally,87 articles were included for analysis. RESULTS AND CONCLUSION:(1)Bioelectrical effect combined with ex vivo electrical stimulation to design bone tissue engineering scaffolds is an ideal and feasible approach,and the main materials involved include metallic materials,graphene materials,natural bio-derived materials,and synthetic biomaterial.At present,the most widely used conductive material is graphene material,which benefits from its super conductivity,large specific surface area,good biocompatibility with cells and bones,and excellent mechanical properties.(2)Graphene materials are mainly introduced into the scaffold as modified materials to enhance the conductivity of the overall scaffold,while its large surface area and rich functional groups can promote the loading and release of bioactive substances.(3)However,there are still some major challenges to overcome for bioelectrically effective bone tissue engineering scaffolds:not only electrical conductivity but also the overall performance of the bracket needs to be considered;lack of uniform,standardized preparation of bioelectrically effective bone tissue engineering scaffolds;extracorporeal electrical stimulation intervention systems are not yet mature enough;lack of individualized guidance on stent selection to enable the selection and design of the most appropriate stent for patients with different pathologies.(4)When designing conductive scaffolds,researchers have to deeply consider the comprehensive effects of the scaffolds,such as biocompatibility,mechanical properties,and biodegradability.This combination of properties can be achieved by combining multiple materials.(5)Beyond that,clinical translation should be the ultimate consideration for conductive stent design.On the basis of evaluating the safe current threshold for electrical stimulation to act on the human body and facilitate the repair of bone defects,animal experiments as well as basic experiments are designed and then applied to the clinic to achieve the ultimate goal of applying bioelectrical effect bone tissue engineering scaffolds in the clinic.

Research progress of traditional Chinese medicine regulating related signaling pathways to promote tendon-bone healing / 中国药房

Tendon-bone healing is a complex biological process. Multiple signaling pathways are involved in tendon-bone healing， including transforming growth factor-β signaling pathway， bone morphogenetic protein signaling pathway， Wnt signaling pathway， fibroblast growth factor signaling pathway and nuclear transcription factor-κB signaling pathway. This paper summarizes the research status of traditional Chinese medicine regulating related signaling pathways to promote tendon-bone healing. It is found that a variety of traditional Chinese medicine monomers or herbal extracts （such as baicalein， icariin， total flavonoids of Drynaria fortunei， parthenolide， total saponins of Panax notoginseng， etc.） and traditional Chinese medicine compounds （such as Taohong siwu decoction， Liuwei dihuang pill， Xujin jiegu liquid， etc.） can promote bone formation， anti-inflammatory， anti-oxidation， by regulating the above signaling pathways， thereby effectively promoting tendon-bone healing.

Study on injectable chitosan hydrogel with tendon-derived stem cells for enhancing rotator cuff tendon-to-bone healing / 中国修复重建外科杂志

OBJECTIVE@#To explore the effect of chitosan (CS) hydrogel loaded with tendon-derived stem cells (TDSCs; hereinafter referred to as TDSCs/CS hydrogel) on tendon-to-bone healing after rotator cuff repair in rabbits.@*METHODS@#TDSCs were isolated from the rotator cuff tissue of 3 adult New Zealand white rabbits by Henderson step-by-step enzymatic digestion method and identified by multidirectional differentiation and flow cytometry. The 3rd generation TDSCs were encapsulated in CS to construct TDSCs/CS hydrogel. The cell counting kit 8 (CCK-8) assay was used to detect the proliferation of TDSCs in the hydrogel after 1-5 days of culture in vitro, and cell compatibility of TDSCs/CS hydrogel was evaluated by using TDSCs alone as control. Another 36 adult New Zealand white rabbits were randomly divided into 3 groups ( n=12): rotator cuff repair group (control group), rotator cuff repair+CS hydrogel injection group (CS group), and rotator cuff repair+TDSCs/CS hydrogel injection group (TDSCs/CS group). After establishing the rotator cuff repair models, the corresponding hydrogel was injected into the tendon-to-bone interface in the CS group and TDSCs/CS group, and no other treatment was performed in the control group. The general condition of the animals was observed after operation. At 4 and 8 weeks, real-time quantitative PCR (qPCR) was used to detect the relative expressions of tendon forming related genes (tenomodulin, scleraxis), chondrogenesis related genes (aggrecan, sex determining region Y-related high mobility group-box gene 9), and osteogenesis related genes (alkaline phosphatase, Runt-related transcription factor 2) at the tendon-to-bone interface. At 8 weeks, HE and Masson staining were used to observe the histological changes, and the biomechanical test was used to evaluate the ultimate load and the failure site of the repaired rotator cuff to evaluate the tendon-to-bone healing and biomechanical properties.@*RESULTS@#CCK-8 assay showed that the CS hydrogel could promote the proliferation of TDSCs ( P<0.05). qPCR results showed that the expressions of tendon-to-bone interface related genes were significantly higher in the TDSCs/CS group than in the CS group and control group at 4 and 8 weeks after operation ( P<0.05). Moreover, the expressions of tendon-to-bone interface related genes at 8 weeks after operation were significantly higher than those at 4 weeks after operation in the TDSCs/CS group ( P<0.05). Histological staining showed the clear cartilage tissue and dense and orderly collagen formation at the tendon-to-bone interface in the TDSCs/CS group. The results of semi-quantitative analysis showed that compared with the control group, the number of cells, the proportion of collagen fiber orientation, and the histological score in the TDSCs/CS group increased, the vascularity decreased, showing significant differences ( P<0.05); compared with the CS group, the proportion of collagen fiber orientation and the histological score in the TDSCs/CS group significantly increased ( P<0.05), while there was no significant difference in the number of cells and vascularity ( P>0.05). All samples in biomechanical testing failed at the repair site during the testing process. The ultimate load of the TDSCs/CS group was significantly higher than that of the control group ( P<0.05), but there was no significant difference compared to the CS group ( P>0.05).@*CONCLUSION@#TDSCs/CS hydrogel can induce cartilage regeneration to promote rotator cuff tendon-to-bone healing.

Value of X-ray tomographic fusion technique in effect assessing after FNS internal fixation of femoral neck fracture / 中国医学装备

Objective:To explore the application value of X-ray tomographic fusion technique in assessing bone healing and osteotylus growth after femoral neck system(FNS)internal fixation of femoral neck fracture.Methods:A total of 18 patients with femoral neck fracture who admitted to the Department of Orthopedics of Beijing Haidian Hospital from October 2019 to June 2020 were selected.All of them were treated with FNS internal fixation,and conventional X-ray and X-ray tomographic fusion imaging were performed respectively at 1 month and 12 months after operation for them.The displays of the two imaging techniques for the bone healing and osteotylus growth after FNS internal fixation of femoral neck fracture were evaluated,and the relevant parameters of the two imaging techniques for the process of image detection of FNS internal fixation of femoral neck fracture were counted by statistical method.Results:The detection rate of X-ray tomographic fusion technique for osteotylus at 1 month after surgery was significantly lower than that at 12 months after surgery.The detection rates(94.44% and 61.11%)of X-ray tomographic fusion technique for osteotylus at 1 month and 12 months after surgery were significantly higher than those(61.11% and 33.33%)of X-ray(x2=5.100,5.790,P<0.05),respectively.The rank-sum test indicated there were significant differences in the distribution of the scores of the image qualities of osteotylus growths at 1 month and 12 months after surgery for patients with femoral neck fracture between two imaging techniques(Z=2.113,2.018,P<0.05),and there were significant differences in the image qualities of bone healing at 1 month and 12 months after surgery between two imaging techniques(Z=2.868,2.258,P<0.05).The display effect of the detection image of fracture site before treatment under the guidance of X-ray tomographic fusion technique was ideal,which images were clear and could display more fully and clearly the fracture line of patient.After 12 months of surgery,the continuous osteotylus that passed fracture line could be found at the anterior lateral position of X-ray,which has reached to clinical healing.In the process of detecting image of FNS internal fixation of femoral neck fracture,the air Kerma,dose area product and effective dose of X-ray tomographic fusion technique were significantly lower than those of conventional X-ray imaging(t=5.900,2.466,32.255,P<0.05),respectively.Conclusion:In the diagnosis and evaluation of bone healing of patients with FNS internal fixation after femoral neck fracture,the use of X-ray tomographic fusion technique can better detect the osteotylus growth of patients and judge the degree of bone healing,especially the judgment effect of that for the postoperative recovery with longer time of patients is more better.In addition,this technique has better safety,which would cause less radiation damage in the process of detection.

Effects of systemic ozone administration on the fresh extraction sockets healing: a histomorphometric and immunohistochemical study in rats

Abstract Studies have highlighted numerous benefits of ozone therapy in the field of medicine and dentistry, including its antimicrobial efficacy against various pathogenic microorganisms, its ability to modulate the immune system effectively, reduce inflammation, prevent hypoxia, and support tissue regeneration. However, its effects on dental extraction healing remain to be elucidated. Objective Therefore, this study aimed to evaluate the effects of systemically administered ozone (O3) at different doses in the healing of dental extraction sockets in rats. Methodology To this end, 72 Wistar rats were randomly divided into four groups after extraction of the right upper central incisor: Group C - control, no systemic treatment; Group OZ0.3 - animals received a single dose of 0.3 mg/kg O3; Group OZ0.7 - a single dose of 0.7 mg/kg O3; and Group OZ1.0 - a single dose of 1.0 mg/kg O3, intraperitoneally. In total, six animals from each group were euthanized at 7, 14, and 21 days after the commencement of treatment. Bone samples were harvested and further analyzed by descriptive histology, histomorphometry, and immunohistochemistry for osteocalcin (OCN) and tartrate-resistant acid phosphatase (TRAP) protein expression. Results All applied doses of O3 were shown to increase the percentage of bone tissue (PBT) after 21 days compared to group C. After 14 days, the OZ0.7 and OZ1.0 groups showed significantly higher PBT when compared to group C. The OZ1.0 group presented the most beneficial results regarding PBT among groups, which denotes a dose-dependent response. OCN immunostaining was higher in all groups at 21 days. However, after seven and 14 days, the OZ1.0 group showed a significant increase in OCN immunostaining compared to C group. No differences in TRAP+ osteoclasts were found between groups and time points. Conclusion Therefore, O3 therapy at higher doses might be beneficial for bone repair of the alveolar socket following tooth extraction.

Effect of Kartogenin combined with adipose-derived stem cells on tendon-bone healing after anterior cruciate ligament reconstruction / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effect of Kartogenin (KGN) combined with adipose-derived stem cells (ADSCs) on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction in rabbits.@*METHODS@#After the primary ADSCs were cultured by passaging, the 3rd generation cells were cultured with 10 μmol/L KGN solution for 72 hours. The supernatant of KGN-ADSCs was harvested and mixed with fibrin glue at a ratio of 1∶1; the 3rd generation ADSCs were mixed with fibrin glue as a control. Eighty adult New Zealand white rabbits were taken and randomly divided into 4 groups: saline group (group A), ADSCs group (group B), KGN-ADSCs group (group C), and sham-operated group (group D). After the ACL reconstruction model was prepared in groups A-C, the saline, the mixture of ADSCs and fibrin glue, and the mixture of supernatant of KGN-ADSCs and fibrin glue were injected into the tendon-bone interface and tendon gap, respectively. ACL was only exposed without other treatment in group D. The general conditions of the animals were observed after operation. At 6 and 12 weeks, the tendon-bone interface tissues and ACL specimens were taken and the tendon-bone healing was observed by HE staining, c-Jun N-terminal kinase (JNK) immunohistochemical staining, and TUNEL apoptosis assay. The fibroblasts were counted, and the positive expression rate of JNK protein and apoptosis index (AI) were measured. At the same time point, the tensile strength test was performed to measure the maximum load and the maximum tensile distance to observe the biomechanical properties.@*RESULTS@#Twenty-eight rabbits were excluded from the study due to incision infection or death, and finally 12, 12, 12, and 16 rabbits in groups A-D were included in the study, respectively. After operation, the tendon-bone interface of groups A and B healed poorly, while group C healed well. At 6 and 12 weeks, the number of fibroblasts and positive expression rate of JNK protein in group C were significantly higher than those of groups A, B, and D (P<0.05). Compared with 6 weeks, the number of fibroblasts gradually decreased and the positive expression rate of JNK protein and AI decreased in group C at 12 weeks after operation, with significant differences (P<0.05). Biomechanical tests showed that the maximum loads at 6 and 12 weeks after operation in group C were higher than in groups A and B, but lower than those in group D, while the maximum tensile distance results were opposite, but the differences between groups were significant (P<0.05).@*CONCLUSION@#After ACL reconstruction, local injection of a mixture of KGN-ADSCs and fibrin glue can promote the tendon-bone healing and enhance the mechanical strength and tensile resistance of the tendon-bone interface.

Research progress on bioactive strategies for promoting tendon graft healing after anterior cruciate ligament reconstruction / 中国修复重建外科杂志

OBJECTIVE@#To review the bioactive strategies that enhance tendon graft healing after anterior cruciate ligament reconstruction (ACLR), and to provide insights for improving the therapeutic outcomes of ACLR.@*METHODS@#The domestic and foreign literature related to the bioactive strategies for promoting the healing of tendon grafts after ACLR was extensively reviewed and summarized.@*RESULTS@#At present, there are several kinds of bioactive materials related to tendon graft healing after ACLR: growth factors, cells, biodegradable implants/tissue derivatives. By constructing a complex interface simulating the matrix, environment, and regulatory factors required for the growth of native anterior cruciate ligament (ACL), the growth of transplanted tendons is regulated at different levels, thus promoting the healing of tendon grafts. Although the effectiveness of ACLR has been significantly improved in most studies, most of them are still limited to the early stage of animal experiments, and there is still a long way to go from the real clinical promotion. In addition, limited by the current preparation technology, the bionics of the interface still stays at the micron and millimeter level, and tends to be morphological bionics, and the research on the signal mechanism pathway is still insufficient.@*CONCLUSION@#With the further study of ACL anatomy, development, and the improvement of preparation technology, the research of bioactive strategies to promote the healing of tendon grafts after ACLR is expected to be further promoted.

Research on Runx2 gene induced differentiation of human amniotic mesenchymal stem cells into ligament fibroblasts in vitro and promotion of tendon-bone healing in rabbits / 中国修复重建外科杂志

OBJECTIVE@#To investigate whether the Runx2 gene can induce the differentiation of human amniotic mesenchymal stem cells (hAMSCs) to ligament fibroblasts in vitro and promote the tendon-bone healing in rabbits.@*METHODS@#hAMSCs were isolated from the placentas voluntarily donated from healthy parturients and passaged, and then identified by flow cytometric identification. Adenoviral vectors carrying Runx2 gene (Ad-Runx2) and empty vector adenovirus (Ad-NC) were constructed and viral titer assay; then, the 3rd generation hAMSCs were transfected with Ad-Runx2 (Ad-Runx2 group) or Ad-NC (Ad-NC group). The real-time fluorescence quantitative PCR and Western blot were used to detect Runx2 gene and protein expression to verify the effectiveness of Ad-Runx2 transfection of hAMSCs; and at 3 and 7 days after transfection, real-time fluorescence quantitative PCR was further used to detect the expressions of ligament fibroblast-related genes [vascular endothelial growth factor (VEGF), collagen type Ⅰ, Fibronectin, and Tenascin-C]. The hAMSCs were used as a blank control group. The hAMSCs, hAMSCs transfected with Ad-NC, and hAMSCs were mixed with Matrigel according to the ratio of 1 : 1 and 1 : 2 to construct the cell-scaffold compound. Cell proliferation was detected by cell counting kit 8 (CCK-8) assay, and the corresponding cell-scaffold compound with better proliferation were taken for subsequent animal experiments. Twelve New Zealand white rabbits were randomly divided into 4 groups of sham operation group (Sham group), anterior cruciate ligament reconstruction group (ACLR group), anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-NC-scaffold compound group (Ad-NC group), and anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-Runx2-scaffold compound group (Ad-Runx2 group), with 3 rabbits in each group. After preparing the ACL reconstruction model, the Ad-NC group and the Ad-Runx2 group injected the optimal hAMSCs-Matrigel compunds into the bone channel correspondingly. The samples were taken for gross, histological (HE staining and sirius red staining), and immunofluorescence staining observation at 1 month after operation to evaluate the inflammatory cell infiltration as well as collagen and Tenascin-C content in the ligament tissues.@*RESULTS@#Flow cytometric identification of the isolated cells conformed to the phenotypic characteristics of MSCs. The Runx2 gene was successfully transfected into hAMSCs. Compared with the Ad-NC group, the relative expressions of VEGF and collagen type Ⅰ genes in the Ad-Runx2 group significantly increased at 3 and 7 days after transfection ( P<0.05), Fibronectin significantly increased at 3 days ( P<0.05), and Tenascin-C significantly increased at 3 days and decreased at 7 days ( P<0.05). CCK-8 detection showed that there was no significant difference ( P>0.05) in the cell proliferation between groups and between different time points after mixed culture of two ratios. So the cell-scaffold compound constructed in the ratio of 1∶1 was selected for subsequent experiments. Animal experiments showed that at 1 month after operation, the continuity of the grafted tendon was complete in all groups; HE staining showed that the tissue repair in the Ad-Runx2 group was better and there were fewer inflammatory cells when compared with the ACLR group and the Ad-NC group; sirius red staining and immunofluorescence staining showed that the Ad-Runx2 group had more collagen typeⅠ and Ⅲ fibers, tending to form a normal ACL structure. However, the fluorescence intensity of Tenascin-C protein was weakening when compared to the ACLR and Ad-NC groups.@*CONCLUSION@#Runx2 gene transfection of hAMSCs induces directed differentiation to ligament fibroblasts and promotes tendon-bone healing in reconstructed anterior cruciate ligament in rabbits.

Suckermouth catfish bone extract as bone graft raw material for bone-healing promotes bone growth in bone loss / Extrato de osso de bagre como material de reparo promove o crescimento ósseo em perda óssea

Objective: This study aimed to evaluate the properties of suckermouth catfish bone extract, which allows it to be adopted as a raw material for bone graft following its graft in an artificial defect of a rat model. Material and Methods: Hydroxyapatite (HA) from suckermouth catfish bone extract was characterized using Fourier-transform infrared spectroscopy (FTIR), and its toxicity was evaluated by Brine Shrimp Lethality Test (BSLT). This material was grafted on artificial defects in rats' femoral bones, which were observed immunologically by Enzyme-linked immunosorbent assay (ELISA) after one week and four weeks, and radiographically in the second week, and histologically in the second and fourth weeks. Results: FTIR shows that this material consists of phosphate, hydroxyl, and carbonate groups, while the BSLT results show that this material is not toxic. Observations by ELISA showed an increase in the expression of Tumor necrosis factor alpha (TNF-α) in defects with HA in the fourth week. Radiographically the defect did not show closure in the second week. In contrast, histological analysis showed a better bone healing process in the defect, which was applied with the HA of the suckermouth catfish bone. Conclusion: The HA extracted from the suckermouth catfish bone has beneficial properties as an alternative to bone graft raw material and, more investigated needed to support this biomaterial to be used in the treatment of bone loss (AU)

Objetivo: Avaliar as propriedades do extrato de osso de bagre, que permitem sua adoção como material bruto para enxerto ósseo, em um defeito ósseo artificial em ratos. Material e Métodos: A hidroxiapatita (HA) do extrato de osso de bagre foi caracterizada usando espectroscopia infravermelha por transformada de Fourier (FTIR), e sua toxicidade foi avaliada pelo Teste de Letalidade do Camarão de Sal (BSLT). Esse material foi enxertado em defeitos artificiais nos ossos femorais de ratos. Análise imunológica por meio do ensaio imunoenzimático (ELISA) foi realizada uma e quatro semanas após a colocação dos enxertos. Análises radiográficas foram feitas na segunda semana e histológica na segunda e quarta semanas. Resultados: A FTIR mostrou que esse material é composto por grupos de fosfato, hidroxila e carbonato, enquanto os resultados do BSLT mostraram que esse material não é tóxico. As observações pelo ELISA mostraram um aumento na expressão do fator de necrose tumoral alfa (TNF-α) nos defeitos com HA na quarta semana. Radiograficamente, o defeito não apresentou fechamento na segunda semana. Em contraste, a análise histológica mostrou um melhor processo de cicatrização óssea no defeito que foi aplicado com a HA do osso de bagre. Conclusão: A HA extraída do osso de bagre possui propriedades benéficas como alternativa ao material bruto para enxerto ósseo, sendo necessárias mais investigações para apoiar esse biomaterial a ser usado no tratamento da perda óssea.(AU)

Fracture healing, the diamond concept under the scope: Hydroxyapatite and the hexagon / Consolidación de fractura, una mirada al concepto diamante: Hidroxiapatita y el hexágono

Abstract Bone healing after a fracture has many intercalated steps that depend on the host, type of injury, and often the orthopedist. The diamond concept since 2007 has outlined 4 main facets that have to be considered as a model by the treating surgeon at the time of injury and when nonunion develops: osteogenic cells, osteoconductive scaffolds, osteoinduction, and the biomechanical environment. All of these foment fracture healing in optimal circumstances. Yet, this work proposes other facets, such as osteoimmunology and vascularity, to be considered as well in the model. These are as important as the original four, though their correlation to the original work has been less noted until more recent literature. The mindset of the orthopedist must thoroughly analyze all these facets and many more when dealing with nonunion. This work presents, probably the most sig nificant ones, parting from the original 4-corner diamond model and expanding it to a more representative hexagon integrated model. Metaphorically, just like the strongest inorganic constituent of the bone: hydroxyapatite.

Resumen Hay múltiples pasos intercalados en la consolidación de la fractura que dependen del paciente, el tipo de fractura y frecuentemente del ortopedista. Desde su introducción en el año 2007, el concepto del diamante ha delineado 4 facetas o aristas principales que se han de tener en cuenta por el ortopedista en el momento de la lesión y cuando la no-unión de fractura ocurre: células osteogénicas, matrices osteocunductivas, osteoinducción, y el ambiente biomecánico. Otras facetas para tener en cuenta, no menos importantes, son la osteoimmunología y la vascularidad. Estas son tan importantes como las 4 facetas originales, pero la correlación entre las mismas ha sido poco notada o integrada hasta ahora. El ortopedista tratante debe analizar todas ellas en profundidad, especialmente cuando se trata de una no-unión. Este trabajo presenta las más significantes, partiendo del modelo original del diamante de 4 facetas hacia uno más representativo e integrado como el hexágono. Metafóricamente, como el elemento inorgánico más abundante y fuerte en el hueso: la hidroxiapatita.

Three osteotomy methods and bone healing in Ilizarov tibial bone transport / 中华创伤骨科杂志

Objective:To explore the effects of 3 osteotomy methods on the bone healing in Ilizarov tibial bone transport.Methods:The data of 93 patients were retrospectively reviewed who had been treated by Ilizarov single-segment tibial bone transport at Department of Hand Surgery, The Second Hospital of Tangshan from December 2003 to April 2019. Minimally invasive osteotomy was performed in 16 patients [group A: 16 males with an age of (37.1±8.3) years; 5 cases of type Ⅱ and 11 ones of type Ⅲ by Gustilo classification], subperiosteal saw osteotomy in 57 patients [group B: 47 males and 10 females with an age of (39.1±11.8) years; 17 cases of type Ⅱ and 40 ones of type Ⅲ by Gustilo classification] and extraperiosteal wire saw osteotomy in 20 patients [group C: 19 males and one female with an age of (37.7±11.2) years; 18 cases of type Ⅱ and 2 cases of type Ⅲ by Gustilo classification]. The 3 groups were compared in terms of the bone healing index and the Association for the Study and Application of the Method of Ilizarov (ASAMI) functional scores.Results:The 3 groups were comparable because there was no significant difference in the preoperative general data between them ( P>0.05). All the patients were followed up for 19 to 50 months (average, 27.4 months). All patients achieved bony healing, and their associated complications were cured after corresponding treatments. There were no significant differences in the bone healing index between the 3 groups [(53.09±21.88) d/cm for group A, (59.97±33.29) d/cm for group B and (46.20±14.11) d/cm for group C] ( P>0.05). There were no significant differences either in the good to excellent rate by the ASAMI functional scores between the 3 groups (87.5% for group A, 89.5% for group B and 90.0% for group C) ( P> 0.05). Conclusion:All the 3 osteotomy methods may achieve good bony union, leading to similar bone healing indexes and postoperative functional scores.

Stiffness and Stress Distribution of Internal Fixation System for Long Bone Fractures / 医用生物力学

Objective To study distributions of stiffness and stress of each component in internal fixation system for long bone fractures composed of fractured bones (including callus) and bone plates,and propose a method for determining bending stiffness of fracture internal fixation implants. Methods Based on the linear bending theory and composite beam theory, the mechanical model of femoral shaft internal fracture fixing system composed of fractured bones and bone plate was constructed and verified with the finite element model based on artificial femur CT data. The relationship between stress and stiffness of the internal fixation system for long bone fractures was established. Results The three stages (slow-rapid-steady growth) for variation of fractured bone bending stiffness with callus elastic modulus obtained by calculation and analysis were consistent with the three stages of actual bone healing process, which proved accuracy of the theoretical calculation method. Changing patterns for the neutral axis position of internal fracture fixing system composed of fractured bones and bone plate were further obtained, namely, the neutral axis position was close to (away from) the central axis of bone plate when stiffness of bone plate increased (decreased). According to the stress required for fracture healing (0.72-0.80 MPa), the reasonable range for bending stiffness of bone plate was 0.99-4.20 kN·mm2. Conclusions When elastic modulus of the callus was 0.037.00 GPa, bending stiffness of the fractured bones increased rapidly, which was at the stage of bone bridge formation. When elastic modulus of the callus was above 7 GPa, the callus tended to mature. Based on the femur model in this study, when thickness of bone plate was 3.6-6.0 mm and elastic modulus of fractured bones was 3.013.5 GPa, the entire fractured bone section could be effectively stimulated. In this study, when bending stiffness of bone plate was 0.99-4.20 kN·mm2 during the generation stage of bone bridge, it was conducive to bone healing.

Effect of low intensity ultra sound on bone regeneration and healing: a systematic review

ABSTRACT Objective: Low Intensity Pulsed Ultra Sound (LIPUS) is found to have stimulatory effect on bone healing and regeneration. This review aimed to assess whether LIPUS enhances bone regeneration and healing in terms of efficiency in improving clinical, radiographic, histologic parameters or serum and tissue biomarkers. Methods: A comprehensive search based on PRISMA guidelines with pre-determined eligibility criteria was conducted to identify randomized controlled clinical trials evaluating effectiveness of Low intensity pulsed ultrasound in bone regeneration and healing. The title and abstract of the entries in all languages yielded from the PubMed, Google scholar and Cochrane library were screened. Results: 14 eligible Randomized controlled trials testing the effectiveness of LIPUS was evaluated. More heterogeneity was seen in the screened studies with respect to sample characteristics, type of bone and outcome measures. The studies that screened histological parameters state that LIPUS is significantly beneficial than control. In terms of time for radiographic union, most of the studies stated that LIPUS was more effective than control but numberof studies are very few. Whereas studies which evaluated parameters such as healing time and radiographic union were showing highly inconsistent results regarding effectiveness of LIPUS. Conclusion: This review cannot give a definitive conclusion that LIPUS is effective in bone healing with respect to clinical parameters but a positive influence on radiographical and histological parameters in bone healing and regeneration is promising to pursue future research.

Evaluation of alkaline phosphatase as a biomarker in the healing progression following tooth extraction / Avaliação da fosfatase alcalina como um biomarcador na progressão da cicatrização após extração dentária

Objetivo: A progressão da cicatrização de um alvéolo após uma extração é geralmente analisada por meio de exame clínico e investigação radiográfica. Embora a cicatrização do tecido mole geralmente seja mantida bem, a progressão da cicatrização do tecido duro é mais difícil de prever e gerenciar, com problemas como alvéolo seco ou má união do osso subjacente. Biomarcadores séricos para progressão da cicatrização óssea, como a Fosfatase Alcalina (FAL), podem ser úteis como ferramenta diagnóstica para intervenção precoce. Material e Métodos:Vinte indivíduos saudáveis de 18-30 anos de idade que deveriam extrair dentes do siso inferiores impactados foram incluídos. Foram coletados 2 ml de sangue, antes do tratamento e 48 horas depois, as amostras seguintes foram coletadas 1 mês, 2 meses e 3 meses após o procedimento. As radiografias intraorais foram realizadas no final dos três meses. Resultados: Houve uma correlação obtida com a cura e os níveis de FAL em intervalos de tempo de 1, 2 e 3 meses (p <0,05), onde 17 pacientes que tiveram um aumento substancial nos níveis de FAL também tiveram cura satisfatória após três meses. Três indivíduos que não apresentaram aumento no nível de FAL não tiveram cura satisfatória. Conclusão: FAL é um biomarcador suplementar útil para a consolidação óssea (AU)

Objective: The progression of a healing socket following an extraction is usually analysed through clinical examination and radiographic investigation. Whilst soft tissue healing is usually maintained well, healing progression of hard tissue is more challenging to predict and manage, with issues such as a dry socket or mal-union of the underlying bone. Serum biomarkers for bone healing progression, such as alkaline phosphatase (ALP), could prove helpful as a diagnostic tool for early intervention. Material and Methods: Twenty healthy 18-30-year-old individuals who were to extract lower impacted wisdom teeth were included. 2ml of blood was collected before treatment, 48 hours after then following samples were collected 1 month, 2 months and 3 months after the procedure. Intra-oral radiographs were taken at the end of the three months. Results: There was a significant correlation elicited with the healing and ALP levels at 1,2 & 3 months' time intervals (p<0.05), where 17 patients who had a substantial increase in the levels of ALP also had satisfactory healing after three months. Three individuals who did not show any increase in ALP level did not have satisfactory healing. Conclusion:ALP is a useful supplementary biomarker for bone healing.(AU)

Characterizations of alveolar repair after mandibular second molar extraction: an experimental study in rats

Abstract Characterizations of rat mandibular second molar extraction socket with significantly different buccal and lingual alveolar ridge width remain unclear. Objective: To observe alterations in the alveolar ridge after extraction of mandibular second molars, and to examine processes of alveolar socket healing in an experimental model of alveolar ridge absorption and preservation. Methodology: Eighteen Wistar rats were included and divided into six groups regarding healing time in the study. Bilateral mandibular second molars were extracted. The rats with tooth extraction sockets took 0, 1.5, 2, 3, 4 and 8 weeks of healing. Histological observation, tartrate-resistant acidic phosphatase (TRAP) staining, Masson's trichrome staining, immunohistochemical staining and micro-computed tomography (micro-CT) were applied to estimate alterations in the alveolar ridge. Results: Different buccal and lingual alveolar ridge width led to different height loss. Lingual wall height (LH) decreased significantly two weeks after tooth extraction. Buccal wall height rarely reduced its higher ridge width. From two to eight weeks after extraction, bone volume (BV/TV), density (BMD), and trabecular thickness (Tb.Th) progressively increased in the alveolar socket, which gradually decreased in Tb.Sp and Tb.N. LH showed no significant change during the same period. Osteogenic marker OCN and OPN increased during bone repair from two to eight weeks. The reduced height of the lingual wall of the tooth extraction socket was rarely repaired in the later repair stage. Osteoclast activity led to absorption of the alveolar ridge of the alveolar bone wall within two weeks after operation. We observed positive expression of EMMPRIN and MMP-9 in osteoclasts that participated in the absorption of the spire region. Conclusion: Extraction of rat mandibular second molars may help the study of alveolar ridge absorption and preservation. The EMMPRIN-MMP-9 pathway may be a candidate for further study on attenuating bone resorption after tooth extraction.

Uso de membrana de colágeno y placa de protección mecánica como instrumento de conservación alveolar / Use of collagen membrane and mechanical protective plate as an instrument for alveolar preservation

Luego de una extracción dental ocurren inevitablemente procesos de reabsorción y remodelación ósea, donde la dimensión y morfología de la cresta alveolar se ve modificada, representando un problema para la rehabilitación de la zona. Estudios clínicos han documentado un promedio de 4,0 a 4,5 mm de reabsorción ósea horizontal luego de una exodoncia, como así también cambios dimensionales significativos en los alrededores del hueso alveolar. El propósito fue evaluar y comparar clínica y tomográficamente los procesos de reparación y conservación del reborde alveolar post-extracción de paredes intactas, con y sin la utilización de esponjas de colágeno intraalveolar como relleno y placa termoformada como barrera física, durante el proceso de cicatrización. Se seleccionaron pacientes con indicación de exodoncia de elementos dentarios normalmente implantados y clínicamente aceptables, aplicando los criterios de exclusión, se realiza toma de impresión del terreno para la confección de una placa de protección rígida 0,8 termoformada para ser colocada posterior a la extracción durante la masticación por un período de 30 días. Se indica tomografía cone-beam post operatoria inmediata y a los tres meses para analizar, medir y comparar alto y ancho de crestas alveolares residuales. En la evaluación clínica y tomográfica de los casos estudiados, el grupo control donde se usó únicamente placa de protección alveolar arrojó mejores resultados que el grupo donde se colocaron esponja de colágeno en el interior del alvéolo. Palabras clave: Regeneración ósea, esponja de colágeno, cicatrización ósea, alvéolo postextracción, placa de protección alveolar (AU)

After a tooth extraction, bone resorption and remodeling processes inevitably occurs, where size and morphology of the alveolar crest is modified, representing a problem for the rehabilitation of the area. Clinical studies have documented an average of 4.0 to 4.5 mm of horizontal bone resorption after an extraction, us well us substantial dimensional changes around the alveolar bone. The purpose was to evaluate and compare clinical and tomographically both repair and preservation of post extraction alveolar ridge of intact walls processes, with and without the use of intraalveolar collagen sponges as filler and a thermoformed protective plaque, us physica? barrier, during healing process. Patients with normally implanted and clinically acceptable tooth with extraction indication were selected, applying the exclusion criteria, impression of the field is taken to build a 0.8 rigid thermoformed protective plaque in order to be placed after extraction and used during chewing for a period of 30 days. Immediate and three months post-operative cone beam tomography are indicated to analyze, measure and compare height and width of residual alveolar crests. In the clinical and tomographic evaluation of the cases treated, control group where only alveolar protective plaque was used, showed better results than the group with intraalveolar collagen sponge (AU)