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
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
[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
Guided bone regeneration is one of the most common surgical treatment modalities performed when an additional alveolar bone is required to stabilize dental implants in partially and fully edentulous patients.The addit...Guided bone regeneration is one of the most common surgical treatment modalities performed when an additional alveolar bone is required to stabilize dental implants in partially and fully edentulous patients.The addition of a barrier membrane prevents non-osteogenic tissue invasion into the bone cavity,which is key to the success of guided bone regeneration.Barrier membranes can be broadly classified as non-resorbable or resorbable.In contrast to non-resorbable membranes,resorbable barrier membranes do not require a second surgical procedure for membrane removal.Commercially available resorbable barrier membranes are either synthetically manufactured or derived from xenogeneic collagen.Although collagen barrier membranes have become increasingly popular amongst clinicians,largely due to their superior handling qualities compared to other commercially available barrier membranes,there have been no studies to date that have compared commercially available porcine-derived collagen membranes with respect to surface topography,collagen fibril structure,physical barrier property,and immunogenic composition.This study evaluated three commercially available non-crosslinked porcine-derived collagen membranes(Striate+TM,Bio-Gide®and CreosTM Xenoprotect).Scanning electron microscopy revealed similar collagen fibril distribution on both the rough and smooth sides of the membranes as well as the similar diameters of collagen fibrils.However,D-periodicity of the fibrillar collagen is significantly different among the membranes,with Striate+TM membrane having the closest D-periodicity to native collagen I.This suggests that there is less deformation of collagen during manufacturing process.All collagen membranes showed superior barrier property evidenced by blocking 0.2–16.4µm beads passing through the membranes.To examine the immunogenic agents in these membranes,we examined the membranes for the presence of DNA and alpha-gal by immunohistochemistry.No alpha-gal or DNA was detected in any membranes.However,using a more sensitive detection method(real-time polymerase chain reaction),a relatively strong DNA signal was detected in Bio-Gide®membrane,but not Striate+TM and CreosTM Xenoprotect membranes.Our study concluded that these membranes are similar but not identical,probably due to the different ages and sources of porcine tissues,as well as different manufacturing processes.We recommend further studies to understand the clinical implications of these findings.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
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
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
The aimof this study was to investigate titaniummembranes(TMs)layered between poly(lactic-co-glycolic acid)(PLGA)containing fluvastatin(FS)for use in guided bone regeneration.Membranes consisting of PLGA,FS-containing...The aimof this study was to investigate titaniummembranes(TMs)layered between poly(lactic-co-glycolic acid)(PLGA)containing fluvastatin(FS)for use in guided bone regeneration.Membranes consisting of PLGA,FS-containing PLGA(PLGA–FS),TM layered between PLGA(TM–PLGA)and TM layered between FS-containing PLGA(TM–PLGA–FS)were prepared,and their mechanical and chemical properties were evaluated.The TM groups showed statistically significant differences,in terms of tensile strength and elastic modulus,when compared to the PLGA groups.The release of FS was demonstrated to be higher in the TM–PLGA–FS group than the PLGA–FS group after Day 14.The effect of membrane implantation on the calvaria of Wistar rats was measured using micro-computed tomography(micro-CT)and morphometrical analyses,as well as histological observations.At 4weeks,the TM–PLGA–FS and TM–PLGA groups were found to have lower bone mineral density but higher bone formation,when compared to the control and PLGA groups.At 8weeks,the use of TM–PLGA–FS membranes significantly enhanced bone formation in the calvaria model,compared to the other groups.These results suggest that a TM layered between PLGA containing FS potentially enhances bone formation,thus showing good potential as a GBR membrane.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
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
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
Platelet-rich fibrin(PRF)is widely used in dentistry and other fields of medicine,and its use has become popular in dental implantology.In several published studies,PRF has been used as a barrier membrane.A barrier me...Platelet-rich fibrin(PRF)is widely used in dentistry and other fields of medicine,and its use has become popular in dental implantology.In several published studies,PRF has been used as a barrier membrane.A barrier membrane is a sheet of a certain material that acts as a biological and mechanical barrier against the invasion of cells that are not involved in bone formation,such as epithelial cells.Among the basic requirements of a'barrier membrane,occlusivity,stiffness,and space maintenance are the criteria that PRF primarily lacks;therefore,it does not fall under the category of barrier membranes.However,there is evidence that PRF membranes are useful in significantly improving wound healing.Does the PRF membrane act as a barrier?Should we think of adding or subtracting some points from the ideal requirements of a barrier membrane,or should we coin a new term or concept for PRF that will incorporate some features of a barrier membrane and be a combination of tissue engineering and biotechnology?This review is aimed at answering the basic question of whether the PRF membrane should be considered a barrier membrane or whether it is something more beyond the boundaries of a barrier membrane.展开更多
BACKGROUND In this case,platelet-rich fibrin(PRF)was added to guided tissue regeneration as a biomaterial in proper order for immediate planting in aesthetic area with periapical infection.CASE SUMMARY With the histor...BACKGROUND In this case,platelet-rich fibrin(PRF)was added to guided tissue regeneration as a biomaterial in proper order for immediate planting in aesthetic area with periapical infection.CASE SUMMARY With the history of endodontic failure in maxillary central incisor,a 34-year-old female patient required the extraction of maxillary anterior residual root and immediate implantation.Cone beam computed tomography and clinical observation were used to assess the regeneration of soft and bone tissue.Before operation,cone beam computed tomography showed the anterior residual root had serious periapical periodontitis with insufficient labial bone in the aesthetic zone.The patient underwent immediate implant placement and reconstruction of the bone substitution by modified guided bone regeneration.The barrier was a three-layer structure of PRF-collagen membrane-PRF that covered the mixture of PRF and Bio-Oss to promote both osteogenesis and soft tissue healing.At 6 mo postoperatively,the definitive crown was placed after accomplished finial impression.One-year follow-up showed a satisfactory aesthetic effect with no obvious absorption of the labial bone and soft tissue.CONCLUSION The use of PRF in combination with guided bone regeneration can serve as a reliable and simple adjuvant for immediate implanting in infected socket and result in a stable osteogenic effect with good aesthetic outcome.展开更多
The oral and maxillofacial regions have complex anatomical structures and different tissue types,which have vital health and aesthetic functions.Biodegradable metals(BMs)is a promising bioactive materials to treat ora...The oral and maxillofacial regions have complex anatomical structures and different tissue types,which have vital health and aesthetic functions.Biodegradable metals(BMs)is a promising bioactive materials to treat oral and maxillofacial diseases.This review summarizes the research status and future research directions of BMs for oral and maxillofacial applications.Mg-based BMs and Zn-based BMs for bone fracture fixation systems,and guided bone regeneration(GBR)membranes,are discussed in detail.Zn-based BMs with a moderate degradation rate and superior mechanical properties for GBR membranes show great potential for clinical translation.Fe-based BMs have a relatively low degradation rate and insoluble degradation products,which greatly limit their application and clinical translation.Furthermore,we proposed potential future research directions for BMs in the oral and maxillofacial regions,including 3D printed BM bone scaffolds,surface modification for BMs GBR membranes,and BMs containing hydrogels for cartilage regeneration,soft tissue regeneration,and nerve regeneration.Taken together,the progress made in the development of BMs in oral and maxillofacial regions has laid a foundation for further clinical translation.展开更多
To discuss the feasibility of the application of porous Mg-Sr alloy combined with Mg-Sr alloy membrane in the repair of mandibular defects in dogs.The second and third mandibular premolars on both sides were extracted...To discuss the feasibility of the application of porous Mg-Sr alloy combined with Mg-Sr alloy membrane in the repair of mandibular defects in dogs.The second and third mandibular premolars on both sides were extracted from six dogs.The model of mandible buccal fenestration bone defects were prepared after the sockets healed.Twelve bone defects were randomly divided into groups A and B,then Mg-Sr alloy was implanted in bone defects of group A and covered by Mg-Sr alloy membrane while Mg-Sr alloy was implanted in bone defects of group B and covered by mineralized collagen membrane.Bone defects observed on cone beam computed tomographic images and comparing the gray value of the two groups after 4,8 and 12 weeks.After 12 weeks,the healing of bone defects were evaluated by gross observation,X-ray microscopes and histological observation of hard tissue.Bone defects in each group were repaired.At 8 and 12 weeks,the gray value of group A was higher than that of group B(P<0.05).At 12 weeks,the bone volume fraction of group A was higher than that of group B(P<0.05).The newly woven bone in group A is thick and arranged staggered,which was better than that of group B.Porous Mg-Sr alloy combined with Mg-Sr alloy membrane could further promote the repair of mandibular defects,and obtain good osteogenic effect.展开更多
Aim:The aim of this study was to evaluate hard and soft tissue changes following guided bone regeneration(GBR),with occlusive titanium barriers(OTB),in the rehabilitation of partially edentulous atrophic jaws.Vertical...Aim:The aim of this study was to evaluate hard and soft tissue changes following guided bone regeneration(GBR),with occlusive titanium barriers(OTB),in the rehabilitation of partially edentulous atrophic jaws.Vertical bone gain(VBG),horizontal bone width(HBW),and flap thickness(FT)changes,observed between the first and the second surgical stages,were evaluated.Methods:The study included 35 patients(9 men and 26 women;mean age 60±10.53 years)in need of vertical bone augmentation for implant placement.Seventy implants were placed,44 with a one-stage approach(Group A)and 26 with a two-stage approach(Group B).VBG,HBW,and FT were measured and statistically compared.Results:VBG for implants placed in Group B was significantly higher than those placed in Group A(P=0.006).The increased HBW in Group B was highly significant compared to that exhibited in Group A(P=0.000).A highly significant difference was found in FT before and after the GBR in the two groups considered together,for both the upper and lower jaws(P=0.000 for both).Conclusions:OTBs are reliable devices in GBR,yielding predictable results in terms of bone augmentation.In almost all cases(94.3%),a spontaneous increase of the FT,at the second surgical phase,was observed.This could be due to the titanium surface features which increases spontaneously the thickness of soft tissues over the OTB.展开更多
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.
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Guided bone regeneration is one of the most common surgical treatment modalities performed when an additional alveolar bone is required to stabilize dental implants in partially and fully edentulous patients.The addition of a barrier membrane prevents non-osteogenic tissue invasion into the bone cavity,which is key to the success of guided bone regeneration.Barrier membranes can be broadly classified as non-resorbable or resorbable.In contrast to non-resorbable membranes,resorbable barrier membranes do not require a second surgical procedure for membrane removal.Commercially available resorbable barrier membranes are either synthetically manufactured or derived from xenogeneic collagen.Although collagen barrier membranes have become increasingly popular amongst clinicians,largely due to their superior handling qualities compared to other commercially available barrier membranes,there have been no studies to date that have compared commercially available porcine-derived collagen membranes with respect to surface topography,collagen fibril structure,physical barrier property,and immunogenic composition.This study evaluated three commercially available non-crosslinked porcine-derived collagen membranes(Striate+TM,Bio-Gide®and CreosTM Xenoprotect).Scanning electron microscopy revealed similar collagen fibril distribution on both the rough and smooth sides of the membranes as well as the similar diameters of collagen fibrils.However,D-periodicity of the fibrillar collagen is significantly different among the membranes,with Striate+TM membrane having the closest D-periodicity to native collagen I.This suggests that there is less deformation of collagen during manufacturing process.All collagen membranes showed superior barrier property evidenced by blocking 0.2–16.4µm beads passing through the membranes.To examine the immunogenic agents in these membranes,we examined the membranes for the presence of DNA and alpha-gal by immunohistochemistry.No alpha-gal or DNA was detected in any membranes.However,using a more sensitive detection method(real-time polymerase chain reaction),a relatively strong DNA signal was detected in Bio-Gide®membrane,but not Striate+TM and CreosTM Xenoprotect membranes.Our study concluded that these membranes are similar but not identical,probably due to the different ages and sources of porcine tissues,as well as different manufacturing processes.We recommend further studies to understand the clinical implications of these findings.
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.
基金financial assistance from the International Team for Implantology,Young Faculty Mentoring Program to K.K.and A.F.and the Japanese Society for Promotion of Science to A.F.(20K10055).
文摘The aimof this study was to investigate titaniummembranes(TMs)layered between poly(lactic-co-glycolic acid)(PLGA)containing fluvastatin(FS)for use in guided bone regeneration.Membranes consisting of PLGA,FS-containing PLGA(PLGA–FS),TM layered between PLGA(TM–PLGA)and TM layered between FS-containing PLGA(TM–PLGA–FS)were prepared,and their mechanical and chemical properties were evaluated.The TM groups showed statistically significant differences,in terms of tensile strength and elastic modulus,when compared to the PLGA groups.The release of FS was demonstrated to be higher in the TM–PLGA–FS group than the PLGA–FS group after Day 14.The effect of membrane implantation on the calvaria of Wistar rats was measured using micro-computed tomography(micro-CT)and morphometrical analyses,as well as histological observations.At 4weeks,the TM–PLGA–FS and TM–PLGA groups were found to have lower bone mineral density but higher bone formation,when compared to the control and PLGA groups.At 8weeks,the use of TM–PLGA–FS membranes significantly enhanced bone formation in the calvaria model,compared to the other groups.These results suggest that a TM layered between PLGA containing FS potentially enhances bone formation,thus showing good potential as a GBR membrane.
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.
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.
文摘Platelet-rich fibrin(PRF)is widely used in dentistry and other fields of medicine,and its use has become popular in dental implantology.In several published studies,PRF has been used as a barrier membrane.A barrier membrane is a sheet of a certain material that acts as a biological and mechanical barrier against the invasion of cells that are not involved in bone formation,such as epithelial cells.Among the basic requirements of a'barrier membrane,occlusivity,stiffness,and space maintenance are the criteria that PRF primarily lacks;therefore,it does not fall under the category of barrier membranes.However,there is evidence that PRF membranes are useful in significantly improving wound healing.Does the PRF membrane act as a barrier?Should we think of adding or subtracting some points from the ideal requirements of a barrier membrane,or should we coin a new term or concept for PRF that will incorporate some features of a barrier membrane and be a combination of tissue engineering and biotechnology?This review is aimed at answering the basic question of whether the PRF membrane should be considered a barrier membrane or whether it is something more beyond the boundaries of a barrier membrane.
基金Supported by Department of Finance of Jilin Province,No.JCSZ2019378-21 and JCSZ2019378-27Jilin Scientific and Technological Development Program,No.20200201302JC.
文摘BACKGROUND In this case,platelet-rich fibrin(PRF)was added to guided tissue regeneration as a biomaterial in proper order for immediate planting in aesthetic area with periapical infection.CASE SUMMARY With the history of endodontic failure in maxillary central incisor,a 34-year-old female patient required the extraction of maxillary anterior residual root and immediate implantation.Cone beam computed tomography and clinical observation were used to assess the regeneration of soft and bone tissue.Before operation,cone beam computed tomography showed the anterior residual root had serious periapical periodontitis with insufficient labial bone in the aesthetic zone.The patient underwent immediate implant placement and reconstruction of the bone substitution by modified guided bone regeneration.The barrier was a three-layer structure of PRF-collagen membrane-PRF that covered the mixture of PRF and Bio-Oss to promote both osteogenesis and soft tissue healing.At 6 mo postoperatively,the definitive crown was placed after accomplished finial impression.One-year follow-up showed a satisfactory aesthetic effect with no obvious absorption of the labial bone and soft tissue.CONCLUSION The use of PRF in combination with guided bone regeneration can serve as a reliable and simple adjuvant for immediate implanting in infected socket and result in a stable osteogenic effect with good aesthetic outcome.
基金the National Natural Science Foundation of China[grant numbers 51901003,51931001,51871004,and 81771039]the National Key R&D Program of China[grant number 2018YFE0104200]+1 种基金the Key Research and Development Program of Ningxia Hui Autonomous Region[grant number 2018BEG02012]the Open Project of NMPA Key laboratory for Dental Materials[grant number PKUSS20200401].
文摘The oral and maxillofacial regions have complex anatomical structures and different tissue types,which have vital health and aesthetic functions.Biodegradable metals(BMs)is a promising bioactive materials to treat oral and maxillofacial diseases.This review summarizes the research status and future research directions of BMs for oral and maxillofacial applications.Mg-based BMs and Zn-based BMs for bone fracture fixation systems,and guided bone regeneration(GBR)membranes,are discussed in detail.Zn-based BMs with a moderate degradation rate and superior mechanical properties for GBR membranes show great potential for clinical translation.Fe-based BMs have a relatively low degradation rate and insoluble degradation products,which greatly limit their application and clinical translation.Furthermore,we proposed potential future research directions for BMs in the oral and maxillofacial regions,including 3D printed BM bone scaffolds,surface modification for BMs GBR membranes,and BMs containing hydrogels for cartilage regeneration,soft tissue regeneration,and nerve regeneration.Taken together,the progress made in the development of BMs in oral and maxillofacial regions has laid a foundation for further clinical translation.
基金supported by Science and Technology Fund of Liaoning Province(20180530071).
文摘To discuss the feasibility of the application of porous Mg-Sr alloy combined with Mg-Sr alloy membrane in the repair of mandibular defects in dogs.The second and third mandibular premolars on both sides were extracted from six dogs.The model of mandible buccal fenestration bone defects were prepared after the sockets healed.Twelve bone defects were randomly divided into groups A and B,then Mg-Sr alloy was implanted in bone defects of group A and covered by Mg-Sr alloy membrane while Mg-Sr alloy was implanted in bone defects of group B and covered by mineralized collagen membrane.Bone defects observed on cone beam computed tomographic images and comparing the gray value of the two groups after 4,8 and 12 weeks.After 12 weeks,the healing of bone defects were evaluated by gross observation,X-ray microscopes and histological observation of hard tissue.Bone defects in each group were repaired.At 8 and 12 weeks,the gray value of group A was higher than that of group B(P<0.05).At 12 weeks,the bone volume fraction of group A was higher than that of group B(P<0.05).The newly woven bone in group A is thick and arranged staggered,which was better than that of group B.Porous Mg-Sr alloy combined with Mg-Sr alloy membrane could further promote the repair of mandibular defects,and obtain good osteogenic effect.
文摘Aim:The aim of this study was to evaluate hard and soft tissue changes following guided bone regeneration(GBR),with occlusive titanium barriers(OTB),in the rehabilitation of partially edentulous atrophic jaws.Vertical bone gain(VBG),horizontal bone width(HBW),and flap thickness(FT)changes,observed between the first and the second surgical stages,were evaluated.Methods:The study included 35 patients(9 men and 26 women;mean age 60±10.53 years)in need of vertical bone augmentation for implant placement.Seventy implants were placed,44 with a one-stage approach(Group A)and 26 with a two-stage approach(Group B).VBG,HBW,and FT were measured and statistically compared.Results:VBG for implants placed in Group B was significantly higher than those placed in Group A(P=0.006).The increased HBW in Group B was highly significant compared to that exhibited in Group A(P=0.000).A highly significant difference was found in FT before and after the GBR in the two groups considered together,for both the upper and lower jaws(P=0.000 for both).Conclusions:OTBs are reliable devices in GBR,yielding predictable results in terms of bone augmentation.In almost all cases(94.3%),a spontaneous increase of the FT,at the second surgical phase,was observed.This could be due to the titanium surface features which increases spontaneously the thickness of soft tissues over the OTB.
