种植体骨界面生物学反应的研究进展

自从Ｂｒａｎｅｍａｒｋ等提出骨整合概念以来,国内外学者在种植牙研究上取得了突破性的进展。种植体植入后能否形成骨整合的界面,不仅取决于种植材料本身的生物相容性、适应症的选择和种植技术,还取决于种植体的表面结构。本文就国外各型种植体骨界面生物反应的研究现状综述如下。１－纯钛螺旋状光滑表面种植体骨界面的生物学反应钝钛种植体表面存在一层金属钛氧化物,钛氧化物受到加工、消毒、外科植入操作、机体等多种因素的影响［１］。在机体环境中,钛表面氧化物的增厚主要由两种机制决定：①金属钛原子向金属钛氧化物表面扩散然后…     

骨质疏松状态下牙种植体骨髓整合改变的实验研究

目的:探索骨质疏松状态下牙种植体骨整合的变化机制,为提高骨质疏松状态下牙种植体成功率奠定基础。材料与方法:6月龄未交配SD雌性大鼠41只随机分为2组,即A:假去势手术组,20只,B:去势手术组,21只。将B组行卵巢切除术,术后1.5月对所有大鼠右股骨远中行牙种植手术,种植纯钛螺钉。分别于种植术后1.5月及3月,随机处死各组大鼠的一半。去势术前、种植术前及处死前分别测量大鼠腰椎3—5、左右股骨远中1/2骨密度。处死后,取右股骨对种植部位进行X线拍片,然后将右股骨沿种植体长轴剖成两半,做扫描电镜观察种植体与骨结合状况,进行骨接触率的测定。结果:1.骨密度:两组大鼠腰椎、左右股骨远中骨密度去势术前大致相同,无显著差异。种植手术前,A组基本保持不变,B组显著降低。1.5月及3月处死时,A组仍基本保持不变,B则持续显著降低。2.骨融合指数(OI):1.5月及3月处死时,A组大于B组,统计分析,差异显著。各组大鼠不同时期处死时,骨融合指数大致相同,统计分析无显著差异。结论:1.不同骨密度下骨整合状况不同,骨密度高,骨整合状况好。2.种植体-骨界面新骨形成后,在没有外界因素作用情况下,延长时间骨整合状况改善不明显。3.骨质疏松改变可使大鼠种植体—骨界面骨融合指数降低。     

纯钛膜在种植外科中应用效果的初步研究

目的 评价无孔纯钛膜治疗种植体周围骨缺损的临床效果，并探讨其应用技巧。方法 81例患者的92颗种植体周围骨缺损均采取自体碎骨及Bio-Oss人工骨移植充填后，国产无孔纯钛膜覆盖治疗，术后6～10个月行种植Ⅱ期手术，同时取出钛膜。结果 5例(6颗种植体)发生种植术后软组织瓣早期裂开或穿孔，钛膜外露且早期取出；其余76例软组织瓣愈合良好，原骨缺损完全骨性修复。结论 钛膜有良好的生物相容性，有效地防止移植的骨代用品移位、纤维结缔组织长入，其塑形性好，能维持较大的骨再生修复空间，骨生成量大。     

前牙种植修复即刻负重的回顾性研究

目的回顾性分析758例HBIC-Ⅰ纯钛人工牙种植体前牙缺失种植修复即刻负重的临床效果。方法对从1997年10月至2007年1月在河北医科大学口腔医院颅颌面种植中心经治的资料完整的758例前牙缺失人工牙种植修复即刻负重病例(共计植入1112颗HBIC-Ⅰ纯钛人工牙种植体)进行回顾性研究。结果1112颗HBIC-Ⅰ纯钛人工牙种植体前牙种植术后观察6个月～10年,累计失败15颗,成功率98.65%;未发现与种植术相关的其他并发症。结论HBIC-Ⅰ纯钛人工牙种植体的临床应用效果较好,能够较好满足临床前牙缺失患者种植修复即刻负重的要求。     

微型支抗种植钉愈合期骨结合状态的组织学观察

目的对纯钛微型种植钉支抗在不同愈合时间下种植体-骨界面的组织形态学变化进行研究.方法采用纯钛种植钉30枚,SPF级新西兰大白兔10只.应用扫描电镜技术及HE染色方法对不同愈合时间下的种植体-骨界面进行观察.结果种植体-骨界面在愈合1周时界面机化为主,出现胶原纤维包绕及局部吸收;无负载愈合2周时,大量胶原纤维包绕,纤细的骨小梁生长明显;4周时,表现为复合骨;愈合8周时层状骨为主,出现二次改建.结论愈合4周是纯钛微型种植钉骨整合组织形态学的一个转折点.     

纯钛种植体表面处理对人牙龈成纤维细胞粘附增殖的影响

在义齿临床种植过程中,形成良好的类似"袖口"状的生物学封闭防止上皮细胞的根方迁移具有关键意义。由于纯钛种植体自身并不具备抗菌能力,所以,对其进行表面处理,得到合适的表面形貌,对于提高种植成功率而言意义重大。研究主要通过分析种植体-软组织的界面特征及生物学宽度,并探讨不同纯钛表面处理对于组织生物学、人牙龈成纤维细胞形态以及增殖活性的影响。     

常规种植术与骨挤压种植术对上颌后牙区Ⅲ类骨种植5年成功率及边缘骨吸收量的影响比较研究

目的　比较常规种植术与骨挤压种植术对上颌后牙区Ⅲ类骨种植5年成功率及边缘骨吸收量的影响。方法　选择2010年1月至2011年12月在中国医科大学附属口腔医院种植中心行上颌后牙区种植修复并且骨质分类为Ⅲ类骨的患者82例（共使用111颗种植体）。以种植体为研究单位,根据是否行骨挤压术,将纳入的病例分为常规种植术组（53颗种植体）和骨挤压种植术组（58颗种植体）。术后随访5年,计算两组种植体5年成功率,并测量种植体植入后半年和1、2、3年时的种植体边缘骨吸收量。比较上颌后牙区Ⅲ类骨行常规种植术与骨挤压种植术对种植体5年成功率及种植体边缘骨吸收量的影响。结果　常规种植术组和骨挤压种植术组种植体5年成功率分别为96.23%和98.28%,两组比较差异无统计学意义（P＞0.05）。种植体植入后半年时,骨挤压种植术组的种植体边缘骨吸收量明显小于常规种植术组,差异有统计学意义（P＜0.05）,而植入后1、2、3年时两组的种植体边缘骨吸收量差异无统计学意义（P＞0.05）。结论　常规种植术和骨挤压种植术对种植体的5年成功率及远期边缘骨吸收量的影响无明显差异。因此,临床中对于上颌后牙区Ⅲ类骨种植病例,术者可根据种植体初期稳定性的需要决定是否行骨挤压术。     

不同管径TiO2纳米管对小型猪体内种植体的基因表达及骨整合的影响

目的探讨表面具有TiO2纳米管结构的纯钛种植体周围的基因表达以及不同管径的纳米管对种植体-骨界面成骨的影响。方法在小型猪体内植入表面具有TiO2纳米管结构的纯钛种植体,术后3周、5周和8周取出种植体骨块,制作不脱钙磨片,利用光学显微镜,观察术后3周、5周和8周种植体周围骨的组织学表现;并采用定量PCR法检测种植体周围alkaline phosphatase（ALP）、osterix（OSX）、collagen-I（COL-I）的表达。结果与机械切削的纯钛种植体相比,表面具有TiO2纳米管结构的纯钛种植体在骨-种植体接触面积和基因表达方面都有显著的增加,尤其是表面具有70nm纳米管的种植体。结论 TiO2纳米管通过调节种植体-骨界面的成骨活动获得良好的分子应答和骨整合,纳米管的管径可以被精确调控以获得更好的骨生成。     

钛网在种植临床应用的系列病案报告

目的:本文目的是研究种植体周围骨缺损采用钛网治疗前后,患者临床和影像学的特征的变化。方法:对12例应用钛网的种植手术进行前瞻性观察研究。收集患者信息、诊断及手术资料,在术前、Ⅰ期术后、Ⅱ期术前三个时间点,通过CBCT观察术区骨量变化,记录种植体成活以及并发症。结果:患者种植时均有骨缺损,应用钛网后术区再生骨量好,种植体均成活,仅一例在I期术后和II期术前出现钛网暴露。12例种植体均成功。讨论:钛网在有骨缺损的种植治疗中有较好的效果,然而治疗过程中存在钛网暴露这一主要并发症。但I期术后钛网晚期暴露并不明显影响成骨及种植体成活。结论:钛网应用对于成骨有良好效果,延迟的钛网暴露对成骨和种植效果无明显不良影响。     

应用一段式骨内种植体的五年临床疗效观察

目的：观察一段式骨内种植体种植后的临床疗效。方法：自1992年9月至1996年11月间应用CDIC纯钛一段式骨内种植体对127例患者采用3种植入方法进行了201颗人工牙种植修复。结果：经5年临床观察201颗种植体中成功177颗，失败24颗，5年总成功率88％。其中即刻种植成功率84.4％(38／45)；早期种植成功率为87．9％(51／58)；延期种植成功率89.8％(88／98)。结论：种植体修复取得长期成功除了种植材料本身性能及设计，也取决于严格的病例选择，熟练掌握外科手术技巧，精确的种植义齿修复系统及长期种植体保健和口腔卫生。     

Pilot clinical and histologic evaluations of a two-piece zirconia implant

An investigation was conducted to evaluate the clinical and histologic results of bone and soft tissue healing around a two-piece zirconia dental implant in a human model. A healthy female patient requiring tooth replacement with dental implants received a two-piece zirconia implant together with conventional titanium implants to be implemented in a prosthesis. Clinical and radiographic evaluations at 6 months revealed stable osseointegrated zirconia and titanium dental implants. Light microscopy and backscatter scanning electron microscopic analyses confirmed the biocompatibility and achievement of osseointegration, in addition to maintenance of the crestal bone level. The findings suggest that the bone-to-implant contact with a zirconia implant surface is sufficient to provide clinical and histologic evidence of osseointegration. The biopsied two-piece zirconia dental implant with platform switching demonstrated osseointegration occlusal to the implant-abutment junction, eliminating the significance of the microgap.     

Advances in surfaces and osseointegration in implantology. Biomimetic surfaces

The present work is a revision of the processes occurring in osseointegration of titanium dental implants according to different types of surfaces -namely, polished surfaces, rough surfaces obtained from subtraction methods, as well as the new hydroxyapatite biomimetic surfaces obtained from thermochemical processes. Hydroxyapatite’s high plasma-projection temperatures have proven to prevent the formation of crystalline apatite on the titanium dental implant, but lead to the formation of amorphous calcium phosphate (i.e., with no crystal structure) instead. This layer produce some osseointegration yet the calcium phosphate layer will eventually dissolve and leave a gap between the bone and the dental implant, thus leading to osseointegration failure due to bacterial colonization. A new surface -recently obtained by thermochemical processes- produces, by crystallization, a layer of apatite with the same mineral content as human bone that is chemically bonded to the titanium surface. Osseointegration speed was tested by means of minipigs, showing bone formation after 3 to 4 weeks, with the security that a dental implant can be loaded. This surface can be an excellent candidate for immediate or early loading procedures. Key words:Dental implants, implants surfaces, osseointegration, biomimetics surfaces.     

Surface Roughness of Dental Implant and Osseointegration

IntroductionDental implants are a usual treatment for the loss of teeth. The success of this therapy is due to the predictability, safety and longevity of the bone–implant interface. Dental implant surface characteristics like roughness, chemical constitution, and mechanical factors can contribute to the early osseointegration. The aim of the present article is to perform a review of the literature on surface roughness of dental implant and osseointegration.MethodologyThis work is a narrative review of some aspects of surface roughness of dental implant and osseointegration.ConclusionDespite technological advancement in the biomaterials field, the ideal surface roughness for osseointegration still remains unclear. In this study about surface nanoroughness of dental implant and osseointegration, the clinical relevance is yet unknown. Innovative findings on nanoroughness are valuable in the fields of dental implantology, maxillofacial or orthopedic implant surfaces and also on cardiovascular implants in permanent contact with patient’s blood.     

Laminin coatings on implant surfaces promote osseointegration: Fact or fiction?

To our knowledge from indexed literature, the role of laminins in the expression of osteogenic biomarkers and osseointegration enhancement has not been systematically reviewed. The aim of the present systematic review was to assess the role of laminin coatings on implant surfaces in promoting osseointegration. To address the focused question, “Do laminin coatings on implant surfaces influence osseointegration?”, indexed databases were searched from 1965 up to and including November 2015 using various combination of the following keywords: “Bone to implant contact”; “implant”; “laminins”; and “osseointegration”. Letters to the Editor, case-reports/case-series, historic reviews, and commentaries were excluded. The pattern of the present systematic review was customized to primarily summarize the pertinent data. Nine studies were included. Six studies were prospective and were performed in animals and 5 studies were in vitro. Results from 8 studies showed that laminin coatings enhanced new bone formation around implants and/or bone-to-implant contact. One study showed that laminin coated implants surfaces did not improve osseointegration. On experimental grounds, laminin coatings seem to enhance osteogenic biomarkers expression and/or osseointegration; however, from a clinical perspective, further randomized control trials are needed to assess the role of laminin coatings in promoting osseointegration around dental implants.     

Temporal sequence of hard and soft tissue healing around titanium dental implants

The objective of the present review was to summarize the evidence available on the temporal sequence of hard and soft tissue healing around titanium dental implants in animal models and in humans. A search was undertaken to find animal and human studies reporting on the temporal dynamics of hard and soft tissue integration of titanium dental implants. Moreover, the influence of implant surface roughness and chemistry on the molecular mechanisms associated with osseointegration was also investigated. The findings indicated that the integration of titanium dental implants into hard and soft tissue represents the result of a complex cascade of biological events initiated by the surgical intervention. Implant placement into alveolar bone induces a cascade of healing events starting with clot formation and continuing with the maturation of bone in contact with the implant surface. From a genetic point of view, osseointegration is associated with a decrease in inflammation and an increase in osteogenesis‐, angiogenesis‐ and neurogenesis‐associated gene expression during the early stages of wound healing. The attachment and maturation of the soft tissue complex (i.e. epithelium and connective tissue) to implants becomes established 6–8 weeks following surgery. Based on the findings of the present review it can be concluded that improved understanding of the mechanisms associated with osseointegration will provide leads and targets for strategies aimed at enhancing the clinical performance of titanium dental implants.     

上颌窦内提升术植骨与不植骨对种植体骨结合的影响

目的探讨上颌窦内提升术植骨与不植骨对种植体骨整合的影响及两者之间的差异。方法将120枚需要进行内提升手术的种植体随机平均分为两组,第一组60枚为实验组,在上颌窦内提升后植入骨材料同期植入种植体;第二组60枚为对照组,上颌窦内提升后不植骨同期植入种植体。对两组种植体进行临床追踪（平均18个月）,观察种植体骨整合、临床检查指标、种植体存留率及影像学变化。结果仅有1例种植体覆盖螺丝暴露,种植体颈部出现骨吸收。所有两组种植体均能完成修复,种植体存留率达到100%,无1例脱落。种植体均能正常行使咀嚼功能,骨整合良好。影像学检查种植体周围均有新骨生长,骨整合良好。结论上颌窦内提升术后不植骨可以取得与植骨同样的效果,可以明显减少患者的种植牙费用,是一种值得推广应用的手术方法。     

Surface treatments of titanium dental implants for rapid osseointegration.

The osseointegration rate of titanium dental implants is related to their composition and surface roughness. Rough-surfaced implants favor both bone anchoring and biomechanical stability. Osteoconductive calcium phosphate coatings promote bone healing and apposition, leading to the rapid biological fixation of implants. The different methods used for increasing surface roughness or applying osteoconductive coatings to titanium dental implants are reviewed. Surface treatments, such as titanium plasma-spraying, grit-blasting, acid-etching, anodization or calcium phosphate coatings, and their corresponding surface morphologies and properties are described. Most of these surfaces are commercially available and have proven clinical efficacy (>95% over 5 years). The precise role of surface chemistry and topography on the early events in dental implant osseointegration remain poorly understood. In addition, comparative clinical studies with different implant surfaces are rarely performed. The future of dental implantology should aim to develop surfaces with controlled and standardized topography or chemistry. This approach will be the only way to understand the interactions between proteins, cells and tissues, and implant surfaces. The local release of bone stimulating or resorptive drugs in the peri-implant region may also respond to difficult clinical situations with poor bone quality and quantity. These therapeutic strategies should ultimately enhance the osseointegration process of dental implants for their immediate loading and long-term success.     

Evaluation of functional dynamics during osseointegration and regeneration associated with oral implants

Objectives: The aim of this paper is to review current investigations on functional assessments of osseointegration and assess correlations to the peri‐implant structure. Material and methods: The literature was electronically searched for studies of promoting dental implant osseointegration, functional assessments of implant stability, and finite element (FE) analyses in the field of implant dentistry, and any references regarding biological events during osseointegration were also cited as background information. Results: Osseointegration involves a cascade of protein and cell apposition, vascular invasion, de novo bone formation and maturation to achieve the primary and secondary dental implant stability. This process may be accelerated by alteration of the implant surface roughness, developing a biomimetric interface, or local delivery of growth‐promoting factors. The current available pre‐clinical and clinical biomechanical assessments demonstrated a variety of correlations to the peri‐implant structural parameters, and functionally integrated peri‐implant structure through FE optimization can offer strong correlation to the interfacial biomechanics. Conclusions: The progression of osseointegration may be accelerated by alteration of the implant interface as well as growth factor applications, and functional integration of peri‐implant structure may be feasible to predict the implant function during osseointegration. More research in this field is still needed. To cite this article:
Chang P‐C, Lang NP, Giannobile WV. Evaluation of functional dynamics during osseointegration and regeneration associated with oral implants.
Clin. Oral Impl. Res. 21 , 2010; 1–12.     

Osseointegration: An Update

Osseointegration, defined as a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant, is critical for implant stability, and is considered a prerequisite for implant loading and long-term clinical success of end osseous dental implants. The implant–tissue interface is an extremely dynamic region of interaction. This complex interaction involves not only biomaterial and biocompatibility issues but also alteration of mechanical environment. The processes of osseointegration involve an initial interlocking between alveolar bone and the implant body, and later, biological fixation through continuous bone apposition and remodeling toward the implant. The process itself is quite complex and there are many factors that influence the formation and maintenance of bone at the implant surface. The aim of this present review is to analysis the current understanding of clinical assessments and factors that determine the success & failure of osseointegrated dental implants.     

Nano-crystalline diamond-coated titanium dental implants – A histomorphometric study in adult domestic pigs

Promising biomaterial characteristics of diamond-coatings in biomedicine have been described in the literature. However, there is a lack of knowledge about implant osseointegration of this surface modification compared to the currently used sandblasted acid-etched Ti-Al6-V4 implants. The aim of this study was to investigate the osseointegration of microwave plasma-chemical-vapour deposition (MWP-CVD) diamond-coated Ti-Al6-V4 dental implants after healing periods of 2 and 5 months.Twenty-four MWP-CVD diamond-coated and 24 un-coated dental titanium-alloy implants (Ankylos^®) were placed in the frontal skull of eight adult domestic pigs. To evaluate the effects of the nano-structured surfaces on bone formation, a histomorphometric analysis was performed after 2 and 5 months of implant healing. Histomorphometry analysed the bone-to-implant contact (BIC). No significant difference in BIC for the diamond-coated implants in comparison to reference implants could be observed for both healing periods. Scanning electron microscopy revealed an adequate interface between the bone and the diamond surface. No delamination or particle-dissociation due to shearing forces could be detected. In this study, diamond-coated dental titanium-alloy implants and sandblasted acid-etched implants showed a comparable degree of osseointegration.