This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. ...This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. Fifty-four （54） rats were studied. A circular bony defect （8 mm diameter） was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group （n= 18）, the CFB-HAP membrane was used to cover the bony defect, and in the control group （n= 18）, a resorbable collagen membrane （Bio-Gide） was used. In the negative control group （n= 18）, no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume （BV） and bone mineral density （BMD） （P〈O.05） between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration （GBR） membrane.展开更多
To develop a biodegradable membrane with guided bone regeneration(GBR),a Mg-2.0Zn-1.0Gd alloy(wt.%,MZG)membrane with Ca-P coating was designed and fabricated in this study.The microstructure,hydrophilicity,in vitro de...To develop a biodegradable membrane with guided bone regeneration(GBR),a Mg-2.0Zn-1.0Gd alloy(wt.%,MZG)membrane with Ca-P coating was designed and fabricated in this study.The microstructure,hydrophilicity,in vitro degradation,cytotoxicity,antibacterial effect and in vivo regenerative performance for the membrane with and without Ca-P coating were evaluated.After coating,the membrane exhibited an enhance hydrophilicity and corrosion resistance,showed good in vitro cytocompatibility upon MC3T3E-1 cells,and exhibited excellent antibacterial effect against E.coli,Staphylococcus epidermis and Staphylococcus aureus,simultaneously.In vivo experiment using the rabbit calvarial defect model confirmed that Ca-P coated MZG membrane underwent progressive degradation without inflammatory reaction and significantly improved the new bone formation at both 1.5 and 3 months after the surgery.All the results strongly indicate that MZG with Ca-P coating have great potential for clinical application as GBR membranes.展开更多
Bioabsorbable chitosan/β-glycerol phosphate （CS/β-GP） composite membranes were fabricated through a relatively PH neutral and mild sol-gel process for guided bone regeneration （GBR）.Their structural properties,m...Bioabsorbable chitosan/β-glycerol phosphate （CS/β-GP） composite membranes were fabricated through a relatively PH neutral and mild sol-gel process for guided bone regeneration （GBR）.Their structural properties,morphology,and tensile strength were investigated.FTIR and XRD analyses indicated that there were chemical bonds between the CS andβ-GP.SEM analysis revealed that the CS/β-GP composite membranes had a porous structure both at the surface and in sublayers.Even though the incorporation ofβ-GP in the CS matrix decreased the initial tensile strength of the membrane,the CS/β-GP membranes were still fit for GBR application with their tensile strength of roughly 1MPa.The concentration ofβ-GP was proportional to the pore size and thickness but was inversely proportional to the tensile strength of the CS/β-GP membrane.The present findings indicate that,based on its characteristics,the CS/β-GP composite membrane is a potential bioresorbable membrane for use in guided bone regeneration.展开更多
BACKGROUND Novel strategies are needed for improving guided bone regeneration(GBR) in oral surgery prior to implant placement, particularly in maxillary sinus augmentation(GBR-MSA) and in lateral alveolar ridge augmen...BACKGROUND Novel strategies are needed for improving guided bone regeneration(GBR) in oral surgery prior to implant placement, particularly in maxillary sinus augmentation(GBR-MSA) and in lateral alveolar ridge augmentation(LRA). This study tested the hypothesis that the combination of freshly isolated, unmodified autologous adipose-derived regenerative cells(UA-ADRCs), fraction 2 of plasma rich in growth factors(PRGF-2) and an osteoinductive scaffold(OIS)(UAADRC/PRGF-2/OIS) is superior to the combination of PRGF-2 and the same OIS alone(PRGF-2/OIS) in GBR-MSA/LRA.CASE SUMMARY A 79-year-old patient was treated with a bilateral external sinus lift procedure as well as a bilateral lateral alveolar ridge augmentation. GBR-MSA/LRA was performed with UA-ADRC/PRGF-2/OIS on the right side, and with PRGF-2/OIS on the left side. Biopsies were collected at 6 wk and 34 wk after GBRMSA/LRA. At the latter time point implants were placed. Radiographs(32 mo follow-up time) demonstrated excellent bone healing. No radiological or histological signs of inflammation were observed. Detailed histologic,histomorphometric, and immunohistochemical analysis of the biopsies evidenced that UA-ADRC/PRGF-2/OIS resulted in better and faster bone regeneration than PRGF-2/OIS.CONCLUSION GBR-MSA with UA-ADRCs, PRGF-2, and an OIS shows effectiveness without adverse effects.展开更多
The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects ...The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects （CSD） using bone marrow-derived mesenchymal stem cells （BMSCs）, and collagen membrane （CM） with and without tricalcium phosphate （TCP） graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD （diameter 4.6 mm） were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone （NFB） and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo pCT. At the lOth week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups I and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical ＂lock＂ between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adiunct BMSC therapy.展开更多
BACKGROUND The odontogenic jaw cyst is a cavity containing liquid,semifluid or gaseous components,with the development of the disease.In recent years,with the rapid development of oral materials and the transformation...BACKGROUND The odontogenic jaw cyst is a cavity containing liquid,semifluid or gaseous components,with the development of the disease.In recent years,with the rapid development of oral materials and the transformation of treatment of jaw cysts,more options are available for treatment of postoperative bone defect of jaw cysts.Guided bone regeneration(GBR)places biomaterials in the bone defect,and then uses biofilm to separate the proliferative soft tissue and the slow-growing bone tissue to maintain the space for bone regeneration,which is widely used in the field of implantology.AIM To observe the clinical effect of GBR in repairing bone defect after enucleation of small and medium-sized odontogenic jaw cysts.METHODS From June 2018 to September 2020,13 patients(7 male,6 female)with odontogenic jaw cysts were treated in the Department of Oral Surgery,Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine.Adults without hypertension,heart disease,diabetes or other systemic diseases were selected.The diagnosis was based on the final pathological results:11 cases were diagnosed as apical cysts,one as primordial cyst,and one as dentigerous cyst.The lesions were located in the maxilla in seven cases,and in the mandible in six cases.All cases were treated with the same method of enucleation combined with GBR.RESULTS Three to four months after the operation,the boundary between the implant site and the surrounding normal stroma was not obvious in patients with small-sized odontogenic jaw cysts.The patients with tooth defects were treated with implant after 6 mo.For the patients with medium-sized odontogenic jaw cysts,the density of the center of the implant area was close to the normal mass at 6 mo after surgery,and there was a clear boundary between the periphery of the implant area and the normal mass.The boundary between the periphery of the implant area and the normal mass was blurred at 8-9 mo after surgery.Patients with tooth defects were treated with implants at>6 mo after the operation.CONCLUSION Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts can shorten the time of osteogenesis,increase the amount of new bone formation,reduce complications,and improve quality of life.展开更多
The aim of this study was to evaluate the accuracy and reproducibility of a morphological contour interpolation(MCI)based segmentation method for the volumetric measurement of bone grafts around implants.Three 3D-prin...The aim of this study was to evaluate the accuracy and reproducibility of a morphological contour interpolation(MCI)based segmentation method for the volumetric measurement of bone grafts around implants.Three 3D-printed models(one with a cylinder and two with a geometrically-complex form)were fabricated to simulate implant placement with a simultaneous guided bone regeneration(GBR)procedure.All models were scanned using a cone beam computed tomography(CBCT)instrument with the same parameters.The true volumes of the bone grafts in the models were assessed using computer-aided calculation(controls).For the test measurements,both manual and MCI-based methods were used.A comparison between the measured and true volumes was performed to evaluate the accuracy.The coefficients of variation of repeated measurements were calculated to evaluate the reproducibility.In addition,the execution time was recorded and a comparison between the two methods was performed.The high accuracy of the MCI-based method was found with differences between the measured value and actual volume,which never exceeded 7.3%.Excellent reproducibility was shown,with coefficients of variation never exceeding 1.1%.A shorter execution time was observed for the MCI-based method than for the manual method.Within the confines of this study,the MCI-based method may be suitable for volumetric measurements of grafted bone around implants.展开更多
Magnesium(Mg)and its alloys have emerged as promising candidates for guided bone/tissue regeneration(GBR/GTR)due to their good mechanical properties,biosafety,and biodegradability.In this study,we present a pioneering...Magnesium(Mg)and its alloys have emerged as promising candidates for guided bone/tissue regeneration(GBR/GTR)due to their good mechanical properties,biosafety,and biodegradability.In this study,we present a pioneering application of Mg-Ag alloys featuring tunable corrosion behaviors for GBR/GTR membranes,showcasing their in vitro antibacterial effects,cell migration,and osteogenic differentiation abilities.Mg-Ag alloys with different Ag contents were engineered to facilitate the cell migration of murine fibroblasts(L929)and the osteogenic differentiation of rat bone mesenchymal stem cells(rBMSCs).The Mg-Ag alloy consisted of recrystallizedα-Mg grains and fine Mg4Ag second phases,with an observable refinement in the average grain size to 5.6μm with increasing Ag content.Among the alloys,Mg-9Ag exhibited optimal mechanical strength and moderate plasticity(tensile yield strength of 205.7 MPa,elongation of 20.3%,and a maximum bending load of 437.2 N).Furthermore,the alloying of Ag accelerated the cathodic reaction of pure Mg,leading to a slightly increased corrosion rate of the Mg-Ag alloys while maintaining acceptable general corrosion.Notably,compared with pure Mg,Mg-Ag alloys had superior antibacterial effects against Porphyromonas gingivalis(P.gingivalis)and Staphylococcus aureus(S.aureus).Taken together,these results provide evidence for the significant clinical potential of Mg-Ag alloys as GBR/GTR membranes.展开更多
Hydrothermally synthesized nano-hydroxyapatite（n-HA ） varmg m wetght Jrom 10% to 30% was used us filler to make guided bone regeneration （ GBR ） composite membranes with navel aliphatic polyesteramide （ PEA ）. T...Hydrothermally synthesized nano-hydroxyapatite（n-HA ） varmg m wetght Jrom 10% to 30% was used us filler to make guided bone regeneration （ GBR ） composite membranes with navel aliphatic polyesteramide （ PEA ）. The structare and properties of PEA and its n- HA composites were investigated through TEM, IR, XRD, SEM and EDX. The shape and size of the n- HA crystals are similar to the apatite crystals in nataral bone. Molecule interactions are present between the n- HA and PEA in the compasite, which allows the uniform dispersion of n- HA in PEA matrix. This contributes enhanced mechanical property and bioactivhy to the compasite. The cytacompatibilhy of the composites has been investigated by culturing osteoblasts on the membranes. Good cell attachment and proliferation manner were observed on the membranes after 1 week. These results suggest that the PEA/ n-HA compasite membrane prepared in this study may serve us barrier membranes for guided bone regeneration and potential candidate scaffold for tissue engineering.展开更多
[Basckground]This case report presented a methodology for immediate implantation in the esthetic zone with a facial bone defect along with flap surgery,guided bone regeneration,and non-submerged healing.[Case presenta...[Basckground]This case report presented a methodology for immediate implantation in the esthetic zone with a facial bone defect along with flap surgery,guided bone regeneration,and non-submerged healing.[Case presentation]A 27-year-old female patient was complaining of the aesthetic complication that was caused via metallic staining of the neck of ceramic crowns in the maxillary right anterior region for one year.She has experienced immediate implantation along with flap surgery,guided bone regeneration(GBR),and non-submerged healing.The torque of the implant reached to the 35 N·cm to confirm primary stability.Six months after surgery,the healing abutment and the implant were fixed,the gingiva was healthy in the surgical area,and the nearby teeth and the opposite teeth were normal.[Results]The results of cone-beam computer tomography(CBCT)revealed that bone defects were filled with the newly formed bone.At the same time,the final impressions accomplished,and an all-ceramic crown was fit-placed.As a whole,the patient satisfaction rate was high.[Conclusions]Immediate implant placement with flap surgery,GBR,and non-submerged healing with a facial bone wall defect in the esthetic zone is an achievable process.展开更多
Objective: to explore the significance of combined guided bone regeneration technique on the basis of jaw cyst curettage in the treatment of patients with odontogenic jaw cyst to improve the treatment quality of patie...Objective: to explore the significance of combined guided bone regeneration technique on the basis of jaw cyst curettage in the treatment of patients with odontogenic jaw cyst to improve the treatment quality of patients. Methods: the project started in October 2020 and the project ended in January 2022. The data composition of the project were all confirmed patients in our hospital, with a total of 54 cases. The project was divided into the general group and the study group, with 27 cases in each group. The treatment parameters, changes in jaw height and width after surgery, treatment efficiency and surgical treatment indexes of the two groups were compared. Results: compared with other groups, the volume and area of cysts in the study group changed more significantly, and the bone mineral density of the patients increased more than that in the general group. Comparing the changes of jaw height and width, the parameters of the study group were higher than those of the conventional group. The number of patients in the study group who showed significant improvement in treatment was larger, and the total effective rate was significantly higher than that in the general group. Compared with the surgical treatment, although the treatment time and blood loss of the study group were more, the incidence of postoperative complications and recurrence rate were lower than those of the general group (P≤0.05). Conclusion: for the patients with odontogenic jaw cyst, the application of combined therapy is of positive significance in improving the disease pathological changes of the patients, improving the overall recovery quality, and reducing the influence of disease complications and recurrence rate.展开更多
Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.M...Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions.展开更多
Severe bone defects pose a formidable clinical challenge in orthopedics,urgently demanding the development of advanced biomaterials to restore structural and functional integrity.While current regenerative materials,s...Severe bone defects pose a formidable clinical challenge in orthopedics,urgently demanding the development of advanced biomaterials to restore structural and functional integrity.While current regenerative materials,such as collagen-containing products,demonstrate a certain degree of biocompatibility,they are still hampered by limitations that include poor mechanical performance,restricted barrier effects,and arduous preparation methods.Here,we report a rapid-curing methodology to engineer recombinant resilin bioshield with tunable modulus,superior bioactivity,and rapid assembly kinetics.The resilin bioshield is rapidly formed within minutes via a tyrosine-mediated photo-crosslinking strategy,achieving spatially programmable assembly.Enzymatic integration of alkaline phosphatase into the resilin matrix drives in situ mineralization,yielding densely packed hydroxyapatite(HAP)nanocrystals.Remarkably,this process enables controlled modulus tuning of the bioshield across three orders of magnitude,achieving an exceptional maximum modulus of 145 MPa while retaining excellent flexibility,thus surpassing conventional guided bone regeneration materials.Beyond its mechanical superiority,the mineralized resilin bioshield not only directs cellular behavior by enhancing adhesion and spreading but also robustly drives the osteogenic differentiation of mesenchymal stem cells,thereby accelerating functional bone regeneration.As a result,our work provides an alternative approach for creating high-performance barrier membranes for guided bone regeneration.展开更多
BACKGROUND Continuous severe horizontal bone defect is common in the aesthetic maxillary anterior area,and presents a major challenge in implant dentistry and requires predictable bone augmentation to increase the wid...BACKGROUND Continuous severe horizontal bone defect is common in the aesthetic maxillary anterior area,and presents a major challenge in implant dentistry and requires predictable bone augmentation to increase the width of the alveolar bone.CASE SUMMARY A 24-year-old man,with a history of well-controlled IgA nephropathy,presented to the Dentistry Department of our hospital complaining of missing his right maxillary anterior teeth 1 mo ago.Severe horizontal alveolar bone defects at sites of teeth 12,13 and 14 were diagnosed.A modified guided bone regeneration surgical approach stabilizing the absorbable collagen membrane and particulate graft materials by periosteal diagonal mattress suture(PDMS)combined with four corner pins was used for this severe continuous horizontal bone defect.The outcome revealed that the newly formed alveolar ridge dimension increased from 0.72 mm to 11.55 mm horizontally 10 mo postoperatively,with no adverse events.The implant surgery was successfully performed.CONCLUSION This case highlights that PDMS combined with four corner pins is feasible to maintain the space and stabilize the graft and membranes in severe continuous horizontal bone defect.展开更多
BACKGROUND In the medical and dental fields,there is a need for studies of new therapeutic approaches for the treatment of bone defects that cause extensive bone loss.Melatonin may be an important endogenous biologica...BACKGROUND In the medical and dental fields,there is a need for studies of new therapeutic approaches for the treatment of bone defects that cause extensive bone loss.Melatonin may be an important endogenous biological factor for bone remodeling,and growth factors may enhance the repair process.AIM To evaluate the gene expression of cytokines(IL-1β,IL-6,IL-10 and TNF-α),markers of osteoclastogenesis(RANK,RANKL and OPG)and MMPs(MMP-1,MMP-2,MMP-8 and MMP-13)from the treatment of melatonin associated with an osteogenic membrane and rhBMP-2 on the recovery of a bone injury.METHODS Sixty-four rats were used and divided into 9 experimental groups and were formed according to the treatment carried out in the region of the bone lesion,which varied between the combination of 1,10 and 100μmol/L of melatonin.Gene Expression analysis was performed using real time-PCR by reading the concentration of total RNA and reverse transcription.RESULTS There were differences between groups when compared with clot or scaffold control,and improvement with a higher concentration of melatonin or rhBMP-2.The combination melatonin(1μg)with 5μg of rhBMP-2,using the guided bone regeneration technique,demonstrated some effects,albeit mild,on bone repair of critical bone defects.CONCLUSION This indicates that the approach for administering these substances needs to be reassessed,with the goal of ensuring their direct application to the affected area.Therefore,future research must be carried out,seeking to produce materials with these ideal characteristics.展开更多
Current challenges in the development of scaffolds for bone regeneration include the engineering of biomaterials that can withstand a natural dynamic physiology on the bone that provides a matrix capable of supporting...Current challenges in the development of scaffolds for bone regeneration include the engineering of biomaterials that can withstand a natural dynamic physiology on the bone that provides a matrix capable of supporting cell migration and tissue ingrowth. The objective of the present work was to develop and characterize a new biomembrane—Mineralized Exoskeleton Shrimp (MES) developed from the exoskeleton of paleomonetes. The integration of MES as a biomaterial for tissue regeneration relies on the growing evidence that the shrimp is characterized by a hierarchically arranged chitin fiber structure, mineralized predominately by calcium carbonate and/or calcium phosphate, bringing beneficial effects in bone regeneration. Additionally, the tridimensional MES structure, can act as a “tent” for Guided Bone Regeneration (GBR). Recently, our team has characterized the MES biomaterial by in vitro (human osteoblastic cellular cultures and immersion of the membrane in modified synthetic plasma) and in vivo (soft tissue in lab mice and hard tissue in rabbit model). The cellular growth in the MES membrane was very exuberant in cellular culture with osteoblastic colonization on its surface (histophilic and biocompatible). After the immersion in modified synthetic plasma for one week, a mass mineralization occurred throughout the membrane’s surface (bioactive). The analysis of histological samples from experimental surgery in lab mice showed that the MES membrane wasn’t toxic to soft tissues and that it caused a moderate inflammatory response (first reabsorption signs at 8 weeks). The MES could act as a cell-guiding template that contains the necessary cues and adequate three-dimensional set to facilitate cell adhesion and promote tissue regeneration upon implantation and subsequent biodegradation.展开更多
Appropriately adapted comprehensive mechanical properties,degradation behavior and biocompatibility are prerequisites for the application of Zn-based biodegradable implants.In this study,hot-extruded Zn-0.5Cu-xFe(x=0....Appropriately adapted comprehensive mechanical properties,degradation behavior and biocompatibility are prerequisites for the application of Zn-based biodegradable implants.In this study,hot-extruded Zn-0.5Cu-xFe(x=0.1,0.2 and 0.4 wt%)alloys were fabricated as candidates for biodegradable materials for guided bone regeneration(GBR)membranes.The hot-extrusion process and Cu alloying were expected mostly to enhance the mechanical properties,and the Fe alloying was added mainly for regulating the degradation.The microstructure,mechanical properties and in vitro degradation behavior were systematically investigated.The ZnCuFe alloys were composed of a Zn matrix and FeZn13 phase.With increasing Fe content,a higher FeZn13 phase precipitation with larger particles was observed.Since elongation declined significantly until fracture with increasing Fe content up to 0.4 wt%,the ZnCuFe(0.2 wt%)alloy achieved a good balance between mechanical strength and ductility,with an ultimate tensile strength of 202.3 MPa and elongation at fracture of 41.2%.Moreover,the addition of Fe successfully accelerated the degradation of ZnCuFe alloys.The ZnCuFe(0.2 wt%)alloy showed relatively uniform corrosion in the long-term degradation test.Furthermore,extracts of the ZnCuFe(0.2 wt%)alloy showed no apparent cytotoxic effects against L929 fibroblasts,Saos-2 osteoblasts or TAg periosteal cells.The ZnCuFe(0.2 wt%)alloy exhibited the potential to inhibit bacterial adhesion of Streptococcus gordonii and mixed oral bacteria.Our study provides evidence that the ZnCuFe(0.2 wt%)alloy can represent a promising material for the application as a suitable GBR membrane.展开更多
To evaluate the clinical efficacy of concentrated growth factors(CGFs)combined with mineralized collagen(MC)in guided bone regeneration(GBR).A retrospective study involving 29 patients treated with GBR technique,which...To evaluate the clinical efficacy of concentrated growth factors(CGFs)combined with mineralized collagen(MC)in guided bone regeneration(GBR).A retrospective study involving 29 patients treated with GBR technique,which was performed either CGF and MC complexes or MC alone.Implants were inserted simultaneously and cone-beam computed tomography was taken immediately,at 3 and 6 months postoperation.Questionnaires were completed by all patients so as to evaluate the main symptoms and daily activities during the first week after surgery.The outcomes of the two groups were statistically compared.All implants healed uneventfully.Patients in both groups suffered from different levels of discomfort for the reason of swelling,pain and chewing impairment on 1-2 days.Meanwhile,swelling of the Trial group was weaker than the Control group.When compared with the Control group,pain levels in Trial group were more rapidly reduced and patients took fewer analgesics from Day 3.Furthermore,the reconstitution mean value of the graft was thicker at 3 and 6 months in Trial group.CGFs complex with MC were beneficial to relieve the clinical symptoms,promote the peri-implant bone regeneration and shorten the healing time.展开更多
Guided bone regeneration(GBR)is a therapeutic procedure used to enhance alveolar bone volume before dental implants.Commercial non-absorbable membranes(i.e.,titanium membranes)typically require a second surgery to rem...Guided bone regeneration(GBR)is a therapeutic procedure used to enhance alveolar bone volume before dental implants.Commercial non-absorbable membranes(i.e.,titanium membranes)typically require a second surgery to remove,whereas absorbable membranes(i.e.,collagen membranes)will fail when put over extensive bone lesions due to their low mechanical strength.The GBR membrane that has been sought is still being developed.Biodegradable metals(BMs),particularly Mg and Zn,have recently been postulated as promising barrier membrane candidates.Herein,the goal of this research is to evaluate the mechanical and biological feasibility of using BMs as GBR membranes.It shows that BMs have a wide range of potential applications as GBR membranes,owing to their benign biocompatibility,sufficient mechanical support,tunable degradation rate,good osteogenic capabilities,broad-spectrum antibacterial behavior,and improved wound healing ability.The rapid degradation rate,hydrogen evolution impact,and stress corrosion cracking behavior all pose obstacles to the use of Mg-based membranes,which can be improved by surface modifications,heat treatment,alloying,etc.Due to its acceptable degradation rate and lack of gas production,Zn appears to be a better candidate for usage as a GBR membrane.In general,advances in the development of BMs have paved the door for BMs to be used as GBR membranes in oral clinical trials.展开更多
Guided bone regeneration membranes have been effectively applied in oral implantology to repair bone defects.However,typical resorbable membranes composed of collagen(Col)have insufficient mechanical properties and hi...Guided bone regeneration membranes have been effectively applied in oral implantology to repair bone defects.However,typical resorbable membranes composed of collagen(Col)have insufficient mechanical properties and high degradation rate,while non-resorbable membranes need secondary surgery.Herein,we designed a photocrosslinkable collagen/polycaprolactone methacryloyl/magnesium(Col/PCLMA/Mg)composite membrane that provided spatiotemporal support effect after photocrosslinking.Magnesium particles were added to the PCLMA solution and Col/PCLMA and Col/PCLMA/Mg membranes were developed;Col membranes and PCL membranes were used as controls.After photocrosslinking,an interpenetrating polymer network was observed by scanning electron microscopy(SEM)in Col/PCL and Col/PCL/Mg membranes.The elastic modulus,swelling behavior,cytotoxicity,cell attachment,and cell proliferation of the membranes were evaluated.Degradation behavior in vivo and in vitro was monitored according to mass change and by SEM.The membranes were implanted into calvarial bone defects of rats for 8 weeks.The Col/PCL and Col/PCL/Mg membranes displayed much higher elastic modulus(p<0.05),and a lower swelling rate(p<0.05),than Col membranes,and there were no differences in cell biocompatibility among groups(p>0.05).The Col/PCL and Col/PCL/Mg membranes had lower degradation rates than the Col membranes,both in vivo and in vitro(p<0.05).The Col/PCL/Mg groups showed enhanced osteogenic capability compared with the Col groups at week 8(p<0.05).The Col/PCL/Mg composite membrane represents a new strategy to display space maintenance and enhance osteogenic potential,which meets clinical needs.展开更多
文摘This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. Fifty-four （54） rats were studied. A circular bony defect （8 mm diameter） was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group （n= 18）, the CFB-HAP membrane was used to cover the bony defect, and in the control group （n= 18）, a resorbable collagen membrane （Bio-Gide） was used. In the negative control group （n= 18）, no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume （BV） and bone mineral density （BMD） （P〈O.05） between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration （GBR） membrane.
基金This work was supported by National Natural Sci-ence Foundation of China(No.81600827,No.U1804251,No.81600827 and No.51971134)the National Key R&D program of China(No.2016YFC1102103)+1 种基金the Science and Technology Commission of Shanghai(18441908000)Shanghai Jiao Tong University Biomedi-cal Engineering Research Fund(YG2019ZDA02).Dr.Jiawen Si wants to thank his wife Qifan Hu and daughter Jinnuo Si for their support,care and love over the past years,and say“thank god for sending you to me on angel’s wings”.
文摘To develop a biodegradable membrane with guided bone regeneration(GBR),a Mg-2.0Zn-1.0Gd alloy(wt.%,MZG)membrane with Ca-P coating was designed and fabricated in this study.The microstructure,hydrophilicity,in vitro degradation,cytotoxicity,antibacterial effect and in vivo regenerative performance for the membrane with and without Ca-P coating were evaluated.After coating,the membrane exhibited an enhance hydrophilicity and corrosion resistance,showed good in vitro cytocompatibility upon MC3T3E-1 cells,and exhibited excellent antibacterial effect against E.coli,Staphylococcus epidermis and Staphylococcus aureus,simultaneously.In vivo experiment using the rabbit calvarial defect model confirmed that Ca-P coated MZG membrane underwent progressive degradation without inflammatory reaction and significantly improved the new bone formation at both 1.5 and 3 months after the surgery.All the results strongly indicate that MZG with Ca-P coating have great potential for clinical application as GBR membranes.
基金Funded by the National Natural Science Foundation of China(No.30870610)the National Glycoengineering Research Center,ShandongUniversity (No.NGRC2009F02)the Shandong Provincial Natural ScienceFoundation (No. Y2008C107)
文摘Bioabsorbable chitosan/β-glycerol phosphate （CS/β-GP） composite membranes were fabricated through a relatively PH neutral and mild sol-gel process for guided bone regeneration （GBR）.Their structural properties,morphology,and tensile strength were investigated.FTIR and XRD analyses indicated that there were chemical bonds between the CS andβ-GP.SEM analysis revealed that the CS/β-GP composite membranes had a porous structure both at the surface and in sublayers.Even though the incorporation ofβ-GP in the CS matrix decreased the initial tensile strength of the membrane,the CS/β-GP membranes were still fit for GBR application with their tensile strength of roughly 1MPa.The concentration ofβ-GP was proportional to the pore size and thickness but was inversely proportional to the tensile strength of the CS/β-GP membrane.The present findings indicate that,based on its characteristics,the CS/β-GP composite membrane is a potential bioresorbable membrane for use in guided bone regeneration.
文摘BACKGROUND Novel strategies are needed for improving guided bone regeneration(GBR) in oral surgery prior to implant placement, particularly in maxillary sinus augmentation(GBR-MSA) and in lateral alveolar ridge augmentation(LRA). This study tested the hypothesis that the combination of freshly isolated, unmodified autologous adipose-derived regenerative cells(UA-ADRCs), fraction 2 of plasma rich in growth factors(PRGF-2) and an osteoinductive scaffold(OIS)(UAADRC/PRGF-2/OIS) is superior to the combination of PRGF-2 and the same OIS alone(PRGF-2/OIS) in GBR-MSA/LRA.CASE SUMMARY A 79-year-old patient was treated with a bilateral external sinus lift procedure as well as a bilateral lateral alveolar ridge augmentation. GBR-MSA/LRA was performed with UA-ADRC/PRGF-2/OIS on the right side, and with PRGF-2/OIS on the left side. Biopsies were collected at 6 wk and 34 wk after GBRMSA/LRA. At the latter time point implants were placed. Radiographs(32 mo follow-up time) demonstrated excellent bone healing. No radiological or histological signs of inflammation were observed. Detailed histologic,histomorphometric, and immunohistochemical analysis of the biopsies evidenced that UA-ADRC/PRGF-2/OIS resulted in better and faster bone regeneration than PRGF-2/OIS.CONCLUSION GBR-MSA with UA-ADRCs, PRGF-2, and an OIS shows effectiveness without adverse effects.
基金King Saud University,through Vice Deanship of Research Chairs
文摘The aim of the present real time in vivo micro-computed tomography （pCT） and histologic experiment was to assess the efficacy of guided bone regeneration （GBR） around standardized calvarial critical size defects （CSD） using bone marrow-derived mesenchymal stem cells （BMSCs）, and collagen membrane （CM） with and without tricalcium phosphate （TCP） graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD （diameter 4.6 mm） were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone （NFB） and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo pCT. At the lOth week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups I and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical ＂lock＂ between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adiunct BMSC therapy.
基金Supported by the National Natural Science Foundation of China,No. 31800816Fundamental Research Program Funding of the Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,No. JYZZ109
文摘BACKGROUND The odontogenic jaw cyst is a cavity containing liquid,semifluid or gaseous components,with the development of the disease.In recent years,with the rapid development of oral materials and the transformation of treatment of jaw cysts,more options are available for treatment of postoperative bone defect of jaw cysts.Guided bone regeneration(GBR)places biomaterials in the bone defect,and then uses biofilm to separate the proliferative soft tissue and the slow-growing bone tissue to maintain the space for bone regeneration,which is widely used in the field of implantology.AIM To observe the clinical effect of GBR in repairing bone defect after enucleation of small and medium-sized odontogenic jaw cysts.METHODS From June 2018 to September 2020,13 patients(7 male,6 female)with odontogenic jaw cysts were treated in the Department of Oral Surgery,Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine.Adults without hypertension,heart disease,diabetes or other systemic diseases were selected.The diagnosis was based on the final pathological results:11 cases were diagnosed as apical cysts,one as primordial cyst,and one as dentigerous cyst.The lesions were located in the maxilla in seven cases,and in the mandible in six cases.All cases were treated with the same method of enucleation combined with GBR.RESULTS Three to four months after the operation,the boundary between the implant site and the surrounding normal stroma was not obvious in patients with small-sized odontogenic jaw cysts.The patients with tooth defects were treated with implant after 6 mo.For the patients with medium-sized odontogenic jaw cysts,the density of the center of the implant area was close to the normal mass at 6 mo after surgery,and there was a clear boundary between the periphery of the implant area and the normal mass.The boundary between the periphery of the implant area and the normal mass was blurred at 8-9 mo after surgery.Patients with tooth defects were treated with implants at>6 mo after the operation.CONCLUSION Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts can shorten the time of osteogenesis,increase the amount of new bone formation,reduce complications,and improve quality of life.
基金the Project of Science and Technology Commission of Shanghai Municipality(No.19411950100)the Multicenter Clinical Research Program of Shanghai Jiao Tong University School of Medicine(No.DLY201822)the Fundamental Research Program Funding of Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine(No.JYZZ102)。
文摘The aim of this study was to evaluate the accuracy and reproducibility of a morphological contour interpolation(MCI)based segmentation method for the volumetric measurement of bone grafts around implants.Three 3D-printed models(one with a cylinder and two with a geometrically-complex form)were fabricated to simulate implant placement with a simultaneous guided bone regeneration(GBR)procedure.All models were scanned using a cone beam computed tomography(CBCT)instrument with the same parameters.The true volumes of the bone grafts in the models were assessed using computer-aided calculation(controls).For the test measurements,both manual and MCI-based methods were used.A comparison between the measured and true volumes was performed to evaluate the accuracy.The coefficients of variation of repeated measurements were calculated to evaluate the reproducibility.In addition,the execution time was recorded and a comparison between the two methods was performed.The high accuracy of the MCI-based method was found with differences between the measured value and actual volume,which never exceeded 7.3%.Excellent reproducibility was shown,with coefficients of variation never exceeding 1.1%.A shorter execution time was observed for the MCI-based method than for the manual method.Within the confines of this study,the MCI-based method may be suitable for volumetric measurements of grafted bone around implants.
基金National Natural Science Found for Distinguished Young Scholars(52225101)National Natural Science Found(52301132)+3 种基金China Postdoctoral Science Foundation(2022M720551)Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0527)Chongqing Academician Special Fund(2022YSZX-JCX0014CSTB)Chongqing Science and Technology Commission(CSTB2022NSCQ-MSX0416)。
文摘Magnesium(Mg)and its alloys have emerged as promising candidates for guided bone/tissue regeneration(GBR/GTR)due to their good mechanical properties,biosafety,and biodegradability.In this study,we present a pioneering application of Mg-Ag alloys featuring tunable corrosion behaviors for GBR/GTR membranes,showcasing their in vitro antibacterial effects,cell migration,and osteogenic differentiation abilities.Mg-Ag alloys with different Ag contents were engineered to facilitate the cell migration of murine fibroblasts(L929)and the osteogenic differentiation of rat bone mesenchymal stem cells(rBMSCs).The Mg-Ag alloy consisted of recrystallizedα-Mg grains and fine Mg4Ag second phases,with an observable refinement in the average grain size to 5.6μm with increasing Ag content.Among the alloys,Mg-9Ag exhibited optimal mechanical strength and moderate plasticity(tensile yield strength of 205.7 MPa,elongation of 20.3%,and a maximum bending load of 437.2 N).Furthermore,the alloying of Ag accelerated the cathodic reaction of pure Mg,leading to a slightly increased corrosion rate of the Mg-Ag alloys while maintaining acceptable general corrosion.Notably,compared with pure Mg,Mg-Ag alloys had superior antibacterial effects against Porphyromonas gingivalis(P.gingivalis)and Staphylococcus aureus(S.aureus).Taken together,these results provide evidence for the significant clinical potential of Mg-Ag alloys as GBR/GTR membranes.
文摘Hydrothermally synthesized nano-hydroxyapatite（n-HA ） varmg m wetght Jrom 10% to 30% was used us filler to make guided bone regeneration （ GBR ） composite membranes with navel aliphatic polyesteramide （ PEA ）. The structare and properties of PEA and its n- HA composites were investigated through TEM, IR, XRD, SEM and EDX. The shape and size of the n- HA crystals are similar to the apatite crystals in nataral bone. Molecule interactions are present between the n- HA and PEA in the compasite, which allows the uniform dispersion of n- HA in PEA matrix. This contributes enhanced mechanical property and bioactivhy to the compasite. The cytacompatibilhy of the composites has been investigated by culturing osteoblasts on the membranes. Good cell attachment and proliferation manner were observed on the membranes after 1 week. These results suggest that the PEA/ n-HA compasite membrane prepared in this study may serve us barrier membranes for guided bone regeneration and potential candidate scaffold for tissue engineering.
文摘[Basckground]This case report presented a methodology for immediate implantation in the esthetic zone with a facial bone defect along with flap surgery,guided bone regeneration,and non-submerged healing.[Case presentation]A 27-year-old female patient was complaining of the aesthetic complication that was caused via metallic staining of the neck of ceramic crowns in the maxillary right anterior region for one year.She has experienced immediate implantation along with flap surgery,guided bone regeneration(GBR),and non-submerged healing.The torque of the implant reached to the 35 N·cm to confirm primary stability.Six months after surgery,the healing abutment and the implant were fixed,the gingiva was healthy in the surgical area,and the nearby teeth and the opposite teeth were normal.[Results]The results of cone-beam computer tomography(CBCT)revealed that bone defects were filled with the newly formed bone.At the same time,the final impressions accomplished,and an all-ceramic crown was fit-placed.As a whole,the patient satisfaction rate was high.[Conclusions]Immediate implant placement with flap surgery,GBR,and non-submerged healing with a facial bone wall defect in the esthetic zone is an achievable process.
文摘Objective: to explore the significance of combined guided bone regeneration technique on the basis of jaw cyst curettage in the treatment of patients with odontogenic jaw cyst to improve the treatment quality of patients. Methods: the project started in October 2020 and the project ended in January 2022. The data composition of the project were all confirmed patients in our hospital, with a total of 54 cases. The project was divided into the general group and the study group, with 27 cases in each group. The treatment parameters, changes in jaw height and width after surgery, treatment efficiency and surgical treatment indexes of the two groups were compared. Results: compared with other groups, the volume and area of cysts in the study group changed more significantly, and the bone mineral density of the patients increased more than that in the general group. Comparing the changes of jaw height and width, the parameters of the study group were higher than those of the conventional group. The number of patients in the study group who showed significant improvement in treatment was larger, and the total effective rate was significantly higher than that in the general group. Compared with the surgical treatment, although the treatment time and blood loss of the study group were more, the incidence of postoperative complications and recurrence rate were lower than those of the general group (P≤0.05). Conclusion: for the patients with odontogenic jaw cyst, the application of combined therapy is of positive significance in improving the disease pathological changes of the patients, improving the overall recovery quality, and reducing the influence of disease complications and recurrence rate.
文摘Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions.
基金supported by grants from the National Key R&D Program of China(Nos.2024YFC2510702,2021YFB3502300,and 2022YFA1206100)the National Natural Science Foundation of China(Nos.22405015,82225012,52473120,82101074,82201017,22125701,52373123,52372278,22361132542,22277064,82202349,22388101,and 22020102003)+4 种基金Beijing Nova Program(Nos.Z211100002121132 and 20220484205)Beijing Natural Science Foundation(Nos.2222010 and L222066)China Postdoctoral Science Foundation(Nos.2022M710257 and 2024M754068)Young Elite Scientist Sponsorship Program by CAST(No.2022QNRC001)C.N.J.thanks the Postdoctoral Fellowship Program of CPSF under Grant Number GZC20231340.
文摘Severe bone defects pose a formidable clinical challenge in orthopedics,urgently demanding the development of advanced biomaterials to restore structural and functional integrity.While current regenerative materials,such as collagen-containing products,demonstrate a certain degree of biocompatibility,they are still hampered by limitations that include poor mechanical performance,restricted barrier effects,and arduous preparation methods.Here,we report a rapid-curing methodology to engineer recombinant resilin bioshield with tunable modulus,superior bioactivity,and rapid assembly kinetics.The resilin bioshield is rapidly formed within minutes via a tyrosine-mediated photo-crosslinking strategy,achieving spatially programmable assembly.Enzymatic integration of alkaline phosphatase into the resilin matrix drives in situ mineralization,yielding densely packed hydroxyapatite(HAP)nanocrystals.Remarkably,this process enables controlled modulus tuning of the bioshield across three orders of magnitude,achieving an exceptional maximum modulus of 145 MPa while retaining excellent flexibility,thus surpassing conventional guided bone regeneration materials.Beyond its mechanical superiority,the mineralized resilin bioshield not only directs cellular behavior by enhancing adhesion and spreading but also robustly drives the osteogenic differentiation of mesenchymal stem cells,thereby accelerating functional bone regeneration.As a result,our work provides an alternative approach for creating high-performance barrier membranes for guided bone regeneration.
文摘BACKGROUND Continuous severe horizontal bone defect is common in the aesthetic maxillary anterior area,and presents a major challenge in implant dentistry and requires predictable bone augmentation to increase the width of the alveolar bone.CASE SUMMARY A 24-year-old man,with a history of well-controlled IgA nephropathy,presented to the Dentistry Department of our hospital complaining of missing his right maxillary anterior teeth 1 mo ago.Severe horizontal alveolar bone defects at sites of teeth 12,13 and 14 were diagnosed.A modified guided bone regeneration surgical approach stabilizing the absorbable collagen membrane and particulate graft materials by periosteal diagonal mattress suture(PDMS)combined with four corner pins was used for this severe continuous horizontal bone defect.The outcome revealed that the newly formed alveolar ridge dimension increased from 0.72 mm to 11.55 mm horizontally 10 mo postoperatively,with no adverse events.The implant surgery was successfully performed.CONCLUSION This case highlights that PDMS combined with four corner pins is feasible to maintain the space and stabilize the graft and membranes in severe continuous horizontal bone defect.
文摘BACKGROUND In the medical and dental fields,there is a need for studies of new therapeutic approaches for the treatment of bone defects that cause extensive bone loss.Melatonin may be an important endogenous biological factor for bone remodeling,and growth factors may enhance the repair process.AIM To evaluate the gene expression of cytokines(IL-1β,IL-6,IL-10 and TNF-α),markers of osteoclastogenesis(RANK,RANKL and OPG)and MMPs(MMP-1,MMP-2,MMP-8 and MMP-13)from the treatment of melatonin associated with an osteogenic membrane and rhBMP-2 on the recovery of a bone injury.METHODS Sixty-four rats were used and divided into 9 experimental groups and were formed according to the treatment carried out in the region of the bone lesion,which varied between the combination of 1,10 and 100μmol/L of melatonin.Gene Expression analysis was performed using real time-PCR by reading the concentration of total RNA and reverse transcription.RESULTS There were differences between groups when compared with clot or scaffold control,and improvement with a higher concentration of melatonin or rhBMP-2.The combination melatonin(1μg)with 5μg of rhBMP-2,using the guided bone regeneration technique,demonstrated some effects,albeit mild,on bone repair of critical bone defects.CONCLUSION This indicates that the approach for administering these substances needs to be reassessed,with the goal of ensuring their direct application to the affected area.Therefore,future research must be carried out,seeking to produce materials with these ideal characteristics.
文摘Current challenges in the development of scaffolds for bone regeneration include the engineering of biomaterials that can withstand a natural dynamic physiology on the bone that provides a matrix capable of supporting cell migration and tissue ingrowth. The objective of the present work was to develop and characterize a new biomembrane—Mineralized Exoskeleton Shrimp (MES) developed from the exoskeleton of paleomonetes. The integration of MES as a biomaterial for tissue regeneration relies on the growing evidence that the shrimp is characterized by a hierarchically arranged chitin fiber structure, mineralized predominately by calcium carbonate and/or calcium phosphate, bringing beneficial effects in bone regeneration. Additionally, the tridimensional MES structure, can act as a “tent” for Guided Bone Regeneration (GBR). Recently, our team has characterized the MES biomaterial by in vitro (human osteoblastic cellular cultures and immersion of the membrane in modified synthetic plasma) and in vivo (soft tissue in lab mice and hard tissue in rabbit model). The cellular growth in the MES membrane was very exuberant in cellular culture with osteoblastic colonization on its surface (histophilic and biocompatible). After the immersion in modified synthetic plasma for one week, a mass mineralization occurred throughout the membrane’s surface (bioactive). The analysis of histological samples from experimental surgery in lab mice showed that the MES membrane wasn’t toxic to soft tissues and that it caused a moderate inflammatory response (first reabsorption signs at 8 weeks). The MES could act as a cell-guiding template that contains the necessary cues and adequate three-dimensional set to facilitate cell adhesion and promote tissue regeneration upon implantation and subsequent biodegradation.
基金the program of project-related personal exchange of person promoting international mobility of researchers(PPP)jointly funded by the(DAAD)German Academic Exchange Service and(CSC)China Scholarship Council:DAAD grant OsteoZink(Project-ID 57390341)This research was funded by National Key Research and Development Plan(Grant No.2016YFC1102500)+1 种基金Sichuan Science and Technology Program Under(Grant No.2020YFH0077)We would like also to thank the Analytical and Testing Center of Southwest Jiaotong University for the characterization analysis and discussion.The authors would also like to acknowledge scientific advice from Dr.Lutz Scheideler and excellent technical assistance of Mr.Ernst Schweizer and Mrs.Evi Kimmerle-Müller from Section Medical Materials Science and Technology,University Hospital Tübingen.
文摘Appropriately adapted comprehensive mechanical properties,degradation behavior and biocompatibility are prerequisites for the application of Zn-based biodegradable implants.In this study,hot-extruded Zn-0.5Cu-xFe(x=0.1,0.2 and 0.4 wt%)alloys were fabricated as candidates for biodegradable materials for guided bone regeneration(GBR)membranes.The hot-extrusion process and Cu alloying were expected mostly to enhance the mechanical properties,and the Fe alloying was added mainly for regulating the degradation.The microstructure,mechanical properties and in vitro degradation behavior were systematically investigated.The ZnCuFe alloys were composed of a Zn matrix and FeZn13 phase.With increasing Fe content,a higher FeZn13 phase precipitation with larger particles was observed.Since elongation declined significantly until fracture with increasing Fe content up to 0.4 wt%,the ZnCuFe(0.2 wt%)alloy achieved a good balance between mechanical strength and ductility,with an ultimate tensile strength of 202.3 MPa and elongation at fracture of 41.2%.Moreover,the addition of Fe successfully accelerated the degradation of ZnCuFe alloys.The ZnCuFe(0.2 wt%)alloy showed relatively uniform corrosion in the long-term degradation test.Furthermore,extracts of the ZnCuFe(0.2 wt%)alloy showed no apparent cytotoxic effects against L929 fibroblasts,Saos-2 osteoblasts or TAg periosteal cells.The ZnCuFe(0.2 wt%)alloy exhibited the potential to inhibit bacterial adhesion of Streptococcus gordonii and mixed oral bacteria.Our study provides evidence that the ZnCuFe(0.2 wt%)alloy can represent a promising material for the application as a suitable GBR membrane.
基金funded by China Postdoctoral Science Foundation Grant(No.2019M652380).
文摘To evaluate the clinical efficacy of concentrated growth factors(CGFs)combined with mineralized collagen(MC)in guided bone regeneration(GBR).A retrospective study involving 29 patients treated with GBR technique,which was performed either CGF and MC complexes or MC alone.Implants were inserted simultaneously and cone-beam computed tomography was taken immediately,at 3 and 6 months postoperation.Questionnaires were completed by all patients so as to evaluate the main symptoms and daily activities during the first week after surgery.The outcomes of the two groups were statistically compared.All implants healed uneventfully.Patients in both groups suffered from different levels of discomfort for the reason of swelling,pain and chewing impairment on 1-2 days.Meanwhile,swelling of the Trial group was weaker than the Control group.When compared with the Control group,pain levels in Trial group were more rapidly reduced and patients took fewer analgesics from Day 3.Furthermore,the reconstitution mean value of the graft was thicker at 3 and 6 months in Trial group.CGFs complex with MC were beneficial to relieve the clinical symptoms,promote the peri-implant bone regeneration and shorten the healing time.
基金supported by the National Key R&D Program of China(2018YFC1106600)the National Natural Science Foundation of China(52071008,and U20A20390)Beijing Natural Science Foundation(2192027)。
文摘Guided bone regeneration(GBR)is a therapeutic procedure used to enhance alveolar bone volume before dental implants.Commercial non-absorbable membranes(i.e.,titanium membranes)typically require a second surgery to remove,whereas absorbable membranes(i.e.,collagen membranes)will fail when put over extensive bone lesions due to their low mechanical strength.The GBR membrane that has been sought is still being developed.Biodegradable metals(BMs),particularly Mg and Zn,have recently been postulated as promising barrier membrane candidates.Herein,the goal of this research is to evaluate the mechanical and biological feasibility of using BMs as GBR membranes.It shows that BMs have a wide range of potential applications as GBR membranes,owing to their benign biocompatibility,sufficient mechanical support,tunable degradation rate,good osteogenic capabilities,broad-spectrum antibacterial behavior,and improved wound healing ability.The rapid degradation rate,hydrogen evolution impact,and stress corrosion cracking behavior all pose obstacles to the use of Mg-based membranes,which can be improved by surface modifications,heat treatment,alloying,etc.Due to its acceptable degradation rate and lack of gas production,Zn appears to be a better candidate for usage as a GBR membrane.In general,advances in the development of BMs have paved the door for BMs to be used as GBR membranes in oral clinical trials.
基金This study was supported by the Innovation research program[HHKT-00-03]the National Natural Science Foundation of China[grant numbers 82170929,81970908,51901003,81200814,and 81771039].
文摘Guided bone regeneration membranes have been effectively applied in oral implantology to repair bone defects.However,typical resorbable membranes composed of collagen(Col)have insufficient mechanical properties and high degradation rate,while non-resorbable membranes need secondary surgery.Herein,we designed a photocrosslinkable collagen/polycaprolactone methacryloyl/magnesium(Col/PCLMA/Mg)composite membrane that provided spatiotemporal support effect after photocrosslinking.Magnesium particles were added to the PCLMA solution and Col/PCLMA and Col/PCLMA/Mg membranes were developed;Col membranes and PCL membranes were used as controls.After photocrosslinking,an interpenetrating polymer network was observed by scanning electron microscopy(SEM)in Col/PCL and Col/PCL/Mg membranes.The elastic modulus,swelling behavior,cytotoxicity,cell attachment,and cell proliferation of the membranes were evaluated.Degradation behavior in vivo and in vitro was monitored according to mass change and by SEM.The membranes were implanted into calvarial bone defects of rats for 8 weeks.The Col/PCL and Col/PCL/Mg membranes displayed much higher elastic modulus(p<0.05),and a lower swelling rate(p<0.05),than Col membranes,and there were no differences in cell biocompatibility among groups(p>0.05).The Col/PCL and Col/PCL/Mg membranes had lower degradation rates than the Col membranes,both in vivo and in vitro(p<0.05).The Col/PCL/Mg groups showed enhanced osteogenic capability compared with the Col groups at week 8(p<0.05).The Col/PCL/Mg composite membrane represents a new strategy to display space maintenance and enhance osteogenic potential,which meets clinical needs.
