Purpose: To investigate the periapical tissue response after root end filling with intermediate restorative material (IRM) and filling of the root-end resection bone defects with autogenous bone or a bone graft substi...Purpose: To investigate the periapical tissue response after root end filling with intermediate restorative material (IRM) and filling of the root-end resection bone defects with autogenous bone or a bone graft substitute in comparison to empty controls. Materials and Methods: Vital roots of the second, third and fourth mandibular premolars in six healthy mongrel dogs were apectomized. The root canals were prepared and sealed with IRM following a standardized surgical procedure. The resection bone defects were either filled with autogenous bone (PB) or one of the bone graft substitutes;CERAMENTTM|BONE VOID FILLER, ChronOS?, TigranTM PTG, Easygraft? CLASSIC or left empty. After 120 days the animals were sacrificed and the specimens were analyzed radiologically and histologically. Kruskal-Wallis and Mann-Whitney tests were performed for statistical evaluation. Results: 34 sections were analyzed histologically. The evaluation revealed a variation in the outcome amongst the tested options, regarding reestablishment of the periapical bone healing and inflammatory infiltration in the sections. According to the tested variables, there was no statistical significant difference between the materials when comparing all groups as a whole. When comparing individual materials to each other there was statistical differences among some of the tested materials. Conclusion: The healing outcome after periapical surgery of a five-wall resection defect could not be increased by infill with autogenous bone or bone graft substitutes. The most important factor for the healing outcome in periapical surgery is the quality of the root-end sealing. The healing outcome after some of the tested bone substitutes, might be improved by longer healing time.展开更多
Bone loss associated with musculoskeletal trauma or metabolic diseases often require bone grafting. The supply of allograft and auto-graft bones is limited. Hence, development of synthetic bone grafting materials is a...Bone loss associated with musculoskeletal trauma or metabolic diseases often require bone grafting. The supply of allograft and auto-graft bones is limited. Hence, development of synthetic bone grafting materials is an active area of research. Chitosan, extracted from chitin present in crawfish shells, was tested as a de-livery vehicle for osteoblasts in a 2-3 mm size defect model in rats. Twenty-seven male Lewis rats, divided into three groups with sacrifice intervals of 3, 6 &9 months were used. In the experimental samples, a critical size defect was filled with chitosan bone graft paste and fixed with a plate, while in the operated control group, a critical size defect was repaired only by a plate (no paste was applied). An unoperated control group was also included. Bone growth was evaluated histologically by examining undecal-cified and decalcified stained sections. The fe-murs were also examined non-destructively by micro-computed tomography (礐T). Defects filled with chitosan bone graft paste demon-strated superior healing across all time periods compared to unfilled defects as examined by histology and micro-computed tomography. Crawfish chitosan has successfully been used as a cell delivery system for osteoblasts for use as a synthetic bone graft material.展开更多
背景:锌基合金医用植入材料有优异的力学性能、完全可降解性、良好的生物相容性,主要用于骨科植入物、心血管支架、胆管支架、气管支架、神经导管等。目的:综述可降解锌基合金应用于骨缺损修复的研究进展,展望锌基材料可期研究方向与成...背景:锌基合金医用植入材料有优异的力学性能、完全可降解性、良好的生物相容性,主要用于骨科植入物、心血管支架、胆管支架、气管支架、神经导管等。目的:综述可降解锌基合金应用于骨缺损修复的研究进展,展望锌基材料可期研究方向与成果。方法:检索PubMed、Web of Science、万方及中国知网数据库,选择各数据库建库至2023年6月收录的各类可降解锌基合金用于骨植入材料研究的相关文献,对生物可降解锌基合金的基本特性进行概述,对锌基合金促进骨组织修复作用进行梳理和归纳总结,讨论当前的研究热点与不足。结果与结论:①锌基合金具备良好的生物相容性,以锌基合金为基体材料,借助支架结构构建技术和涂层优化工艺将有效提高锌基合金的骨传导性,并且使其降解产物具备高效骨诱导性,以调控成骨、破骨细胞的基因表达,促进骨缺损后的修复重建;②然而在锌基合金优化的研究中,涂层工艺相对不足,增材负载技术尚缺乏;③锌基合金拥有良好的机械、生物特性,通过特殊工艺可增加材料的骨传导性、骨诱导性以有效提高其促进骨修复重建能力,并有望进一步实现个性化移植材料的研发。优化涂层与增材负载等技术融合于锌基合金的研究有待进一步探讨。展开更多
Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the com-bination of cells,growth factors and scaffolds.However,the intra/peri-implant region is exposed to se-vere hypoxic...Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the com-bination of cells,growth factors and scaffolds.However,the intra/peri-implant region is exposed to se-vere hypoxic stress and oxidative stress during the early stage of implantation with bone graft materials,which endangers the survival,proliferation and differentiation of seed cells within the implants as well as the host cells surrounding the implants.If the bone graft material could spontaneously and intelligently regulate the hypoxic stress and oxidative stress to a moderate level,it will facilitate the vascularization of the implants and the rapid regeneration of the bone tissue.In this review,we will first introduce the signaling pathways of cellular response under hypoxic stress and oxidative stress,then present the clas-sical material designs and examples in response to hypoxic stress and oxidative stress.And finally,we will address the important role of epigenetic mechanisms in the regulation of hypoxic stress and oxida-tive stress and describe the potential applications and prospective smart bone graft materials based on novel epigenetic factors against hypoxic stress and oxidative stress in bone repair.The main content of this review is summarized in the following graphical abstract.展开更多
文摘Purpose: To investigate the periapical tissue response after root end filling with intermediate restorative material (IRM) and filling of the root-end resection bone defects with autogenous bone or a bone graft substitute in comparison to empty controls. Materials and Methods: Vital roots of the second, third and fourth mandibular premolars in six healthy mongrel dogs were apectomized. The root canals were prepared and sealed with IRM following a standardized surgical procedure. The resection bone defects were either filled with autogenous bone (PB) or one of the bone graft substitutes;CERAMENTTM|BONE VOID FILLER, ChronOS?, TigranTM PTG, Easygraft? CLASSIC or left empty. After 120 days the animals were sacrificed and the specimens were analyzed radiologically and histologically. Kruskal-Wallis and Mann-Whitney tests were performed for statistical evaluation. Results: 34 sections were analyzed histologically. The evaluation revealed a variation in the outcome amongst the tested options, regarding reestablishment of the periapical bone healing and inflammatory infiltration in the sections. According to the tested variables, there was no statistical significant difference between the materials when comparing all groups as a whole. When comparing individual materials to each other there was statistical differences among some of the tested materials. Conclusion: The healing outcome after periapical surgery of a five-wall resection defect could not be increased by infill with autogenous bone or bone graft substitutes. The most important factor for the healing outcome in periapical surgery is the quality of the root-end sealing. The healing outcome after some of the tested bone substitutes, might be improved by longer healing time.
文摘Bone loss associated with musculoskeletal trauma or metabolic diseases often require bone grafting. The supply of allograft and auto-graft bones is limited. Hence, development of synthetic bone grafting materials is an active area of research. Chitosan, extracted from chitin present in crawfish shells, was tested as a de-livery vehicle for osteoblasts in a 2-3 mm size defect model in rats. Twenty-seven male Lewis rats, divided into three groups with sacrifice intervals of 3, 6 &9 months were used. In the experimental samples, a critical size defect was filled with chitosan bone graft paste and fixed with a plate, while in the operated control group, a critical size defect was repaired only by a plate (no paste was applied). An unoperated control group was also included. Bone growth was evaluated histologically by examining undecal-cified and decalcified stained sections. The fe-murs were also examined non-destructively by micro-computed tomography (礐T). Defects filled with chitosan bone graft paste demon-strated superior healing across all time periods compared to unfilled defects as examined by histology and micro-computed tomography. Crawfish chitosan has successfully been used as a cell delivery system for osteoblasts for use as a synthetic bone graft material.
文摘背景:锌基合金医用植入材料有优异的力学性能、完全可降解性、良好的生物相容性,主要用于骨科植入物、心血管支架、胆管支架、气管支架、神经导管等。目的:综述可降解锌基合金应用于骨缺损修复的研究进展,展望锌基材料可期研究方向与成果。方法:检索PubMed、Web of Science、万方及中国知网数据库,选择各数据库建库至2023年6月收录的各类可降解锌基合金用于骨植入材料研究的相关文献,对生物可降解锌基合金的基本特性进行概述,对锌基合金促进骨组织修复作用进行梳理和归纳总结,讨论当前的研究热点与不足。结果与结论:①锌基合金具备良好的生物相容性,以锌基合金为基体材料,借助支架结构构建技术和涂层优化工艺将有效提高锌基合金的骨传导性,并且使其降解产物具备高效骨诱导性,以调控成骨、破骨细胞的基因表达,促进骨缺损后的修复重建;②然而在锌基合金优化的研究中,涂层工艺相对不足,增材负载技术尚缺乏;③锌基合金拥有良好的机械、生物特性,通过特殊工艺可增加材料的骨传导性、骨诱导性以有效提高其促进骨修复重建能力,并有望进一步实现个性化移植材料的研发。优化涂层与增材负载等技术融合于锌基合金的研究有待进一步探讨。
基金financially supported by the National Nat-ural Science Foundation of China(Nos.32071341,82202741,52003302,31430030,51973021,32201111,and 52202358)the Chinese Postdoctoral Science Foundation(Nos.2021M703710 and 2021M691464)+1 种基金the Guangdong Basic and Applied Basic Re-search Foundation(Nos.2021A1515111040,2019A1515110841 and 2019A1515011935)the Beijing Municipal Health Commis-sion(Nos.BMHC-20216 and PXM 2020_026275_000002)。
文摘Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the com-bination of cells,growth factors and scaffolds.However,the intra/peri-implant region is exposed to se-vere hypoxic stress and oxidative stress during the early stage of implantation with bone graft materials,which endangers the survival,proliferation and differentiation of seed cells within the implants as well as the host cells surrounding the implants.If the bone graft material could spontaneously and intelligently regulate the hypoxic stress and oxidative stress to a moderate level,it will facilitate the vascularization of the implants and the rapid regeneration of the bone tissue.In this review,we will first introduce the signaling pathways of cellular response under hypoxic stress and oxidative stress,then present the clas-sical material designs and examples in response to hypoxic stress and oxidative stress.And finally,we will address the important role of epigenetic mechanisms in the regulation of hypoxic stress and oxida-tive stress and describe the potential applications and prospective smart bone graft materials based on novel epigenetic factors against hypoxic stress and oxidative stress in bone repair.The main content of this review is summarized in the following graphical abstract.