不同粗糙表面的纯钛种植体与骨组织界面剪切强度的评价

目的:通过测定不同粗糙度的种植体在不同植入时间的剪切强度的变化,评价不同粗糙度种植体与骨的结合强度。方法:将纯钛的光滑试样、微粗糙表面(I)、微粗糙表面(II)、大粗糙表面等四组植入家兔股骨中,分别在术后一个月和三个月将种植体连同周围的骨组织切下来,进行拉出试验。结果:随着种植体表面粗糙度的增大,界面剪切强度呈增大。随着植入时间的增加,界面剪切强度也呈增大趋势。结论:对于纯钛,不同表面粗糙度的种植体-骨组织界面的剪切强度有明显的差异,随着粗糙度的增大,剪切强度也随之增大;随着植入时间的增加微粗糙与粗糙表面的剪切强度趋向接近。     

不同粗糙表面的纯钛种植体表面的体外细胞培养评价

目的：本文通过对不同粗糙度表面纯钛种植体（光滑、机械表面、大粗糙表面、2种不同的微粗糙表面）的体外细胞培养评价,寻找具有较好的细胞附着的表面状态。方法：对5种不同粗糙度的钛种植体表面进行2BS成纤维细胞培养,通过光镜和电子显微镜对材料表面的成纤维细胞的数量和形态、细胞的粘附状态和细胞与种植体的关系进行了观察和分析。结果：粗糙表面的钛种植体对成纤维细胞的＂诱导能力＂更强,表现为细胞迁徙、附着于二者的细胞数目比光滑表面的钛板为多,细胞桥形成更早。结论：钛种植体表面微粗糙化提高钛材的生物相容性。     

不同粗糙表面的纯钛种植体的耐腐蚀性评价

目的：本文通过对不同粗糙度表面纯钛种植体（光滑、机械表面、大粗糙表面、2种不同的微粗糙表面以及各表面的不同氧化状态）的耐腐蚀性的评价,寻找具有较好的耐腐蚀的表面状态。方法：对5种不同粗糙度及相应的2种氧化表面的种植体进行电化学实验,进行自然腐蚀电位及剩余电位的测定、自然腐蚀电位随时间波动检测、腐蚀速度测定、阳极极化曲线测定。结果：400℃、45min表面氧化的微粗糙表面的钛种植体的耐腐蚀性最好。结论：对微粗糙表面进行适当的氧化处理使种植体表面的保护层增厚,同时使保护层更均匀、一致和致密,从而使种植体的耐腐蚀性能更好,种植体更稳定。     

表面陶瓷化钛种植体的骨组织相容性研究

目的：对新型表面陶瓷化纯钛种植体（Bio-Tiimplant）的骨愈合情况及机理进行研究。方法：设计制作相应的纯钛种植体,采用特殊电化学方法对其表面进行陶瓷化处理,表面未经处理的种植体作为对照,分别植入犬股骨上段,于3周、6周、12周处死动物,对种植体周围骨组织进行组织学观察及评价,分析其微观机理。结果：所有种植体周围没有发现明显炎性组织或形成纤维层,Bio-Ti种植体组新生类骨组织生长较快,并于6周时已形成含有骨小梁及哈弗氏小管结构的较成熟骨组织,对照组12周时新生骨组织基本成熟。结论：Bio-Ti纯钛种植体具有很好的骨组织相容性,并可早期促进种植体周围新生骨组织的形成,缩短骨结合时间。     

微弧氧化钛基种植材料对成骨细胞早期黏附的影响

目的：检测纯钛种植体材料微弧氧化（microarc oxidation，MAO）表面改性后的成骨细胞生物相容性，探讨微弧氧化技术在钛种植体表面改性中的价值。方法：在纯钛种植体材料表面用微弧氧化法制备羟基磷灰石陶瓷薄膜，将MAO改性钛种植体材料作为实验组Ⅰ，将纯钛表面阳极氧化改性处理的种植体材料作为实验组Ⅱ．并设立对照组Ⅰ（纯钛种植体材料）和对照组Ⅱ（即细胞直接生长在培养板上），分别进行扫描电镜（SEM）、能谱分析（EDS）、X射线衍射图谱分析（XRD）等检测，比较成骨细胞的黏附水平，对数据采用SPSS11．0统计软件包进行单因素方差分析。结果：MAO改性后生成粗糙、多孔的陶瓷薄膜层，与处理前电解液成分相比，钙磷比无显著改变。MAO改性钛组黏附的细胞密度显著高于其他组（P〈0．01），而对照组Ⅰ、Ⅱ的细胞密度无显著差异（P〉0．05）。结论：与阳极氧化表面改性材料相比，该钛基微弧氧化薄膜层能够显著促进成骨细胞的附着，具有良好的细胞相容性。     

改良喷砂表面处理提高钛牙种植体骨结合的界面生物力学研究

目的：研究改良喷砂表面处理对钛牙种植体骨界面剪切强度的影响。从界面生物力学角度证实改良喷砂表面处理在钛牙种植体中应用的可行性和应用价值。方法：将光滑表面钛种植体与改良喷砂表面种植体随机植入狗股骨内侧髁,分别于植入后2、4、12周取材,Instron电子拉伸试验机检测种植体骨界面的剪切强度。扫描电镜与X－射线能谱分析仪观察植入12周拔出的种植体表面,并进行元素分析。结果：改良喷砂表面组骨界面剪切强度明显高于光滑表面组,约高出4倍,且植入2周即已获得超出光滑表面组12周所能达到的最大强度。植入12周后拔出的改良喷砂表面种植体表面经扫描电镜观察与X－射线谱分析,提示种植体表面大部分被覆骨组织,粗糙表面的二级窝洞内充满骨样组织。结论：改良喷砂表面处理所获得的粗糙表面可以大大地提高牙种植体骨界面的结合强度。此类粗糙表面所特有的二级窝洞在这里起着重要作用。     

小直径钛锆种植体植入后疼痛的短期临床观察

目的 在牙列缺损的后牙区植入小直径钛锆种植体,评价小直径钛锆种植体的植入术后的患者疼痛反应。方法 用改良牙科焦虑量表筛选出45例非牙科焦虑症患者,患者均为后牙区单牙缺失。随机分为实验组20例（植入3.3 mm直径的软组织水平SLActive钛锆种植体）和对照组25例（植入4.1mm直径的软组织水平SLA纯钛种植体）。通过0~10数字疼痛强度量表（Numerical Rating Scale,NRS）和语言模拟量表（Verbal Rating Scale,VRS）对患者14天内的疼痛水平进行评分并比较。结果 在种植体植入术后的2 h、6 h、1 d和3 d,实验组的疼痛水平均明显低于对照组,差异有统计学意义（P<0.05）;在第7 d和14 d两组疼痛水平的差异无统计学意义（P>0.05）。结论 小直径种植体植入术后的疼痛反应较小。     

钛种植体-骨间隙愈合界面成骨方式的激光共聚焦显微镜观察

目的：观察钛种植体一骨界面的新生骨形成情况，探讨在间隙愈合模型中种植体和骨表面是否存在双向成骨现象。方法：将4枚带有环形凹槽的纯钛种植体经喷砂、酸蚀处理后，植入兔股骨远端髁突内。术后第5d和第19d分别肌肉注射钙黄绿素和茜素红。采用激光共聚焦显微镜观察带种植体的硬组织切片。结果：激光共聚焦显微镜显示，种植体的间隙区域均有新生骨组织生成。在间隙区域，骨创面和相应的种植体表面分别存在绿色荧光带（钙黄绿素），二者问不连续，而在19d时注射的茜素红所标记的红色荧光将二者连接融合，并可见大量红色荧光分布于绿色荧光周围。结论：种植体一骨界面存在远端成骨和接触成骨2种成骨方式，二者相向成骨。     

紫外线处理微弧氧化种植体的早期成骨研究

目的研究C波段紫外线(ultraviolet C,UVC)处理的微弧氧化(micro-arc oxidation,MAO)纯钛种植体植入兔胫骨后的早期成骨方式。方法实验分2组,MAO组和UVC-MAO组。MAO组将医用纯钛种植体经微弧氧化处理后植入新西兰大白兔胫骨。UVC-MAO组将医用纯钛种植体经过微弧氧化处理后,用15 W UVC灭菌灯对钛种植体照射48 h,经过25.0 kGyγ射线消毒后植入新西兰大白兔胫骨。2周后取出胫骨,用锥形束CT观察种植体表面成骨情况;制作胫骨硬组织切片,并以亚甲基蓝-酸性品红染色,光学显微镜观察两组种植体的成骨方式。结果 MAO组可见靠近种植体骨环底端的为成骨细胞及软组织,无任何骨组织,骨环斜面有从周围成熟骨生长的骨组织及类骨质,但所有组织与种植体表面均有一定距离,而非密切接触材料表面。UVC-MAO组可见种植体骨环底端及骨环斜面表面紧密接触类骨质及成骨细胞,还有已经分化的新生骨组织;所有组织与种植体表面紧密接触,无间隔。结论紫外线处理微弧氧化后的种植体,更有利于成骨细胞粘附于种植体表面,形成新生骨质并紧密贴附于种植体表面,骨环周围成熟骨质同时向种植体生长,有利于种植体早期的接触成骨。     

二氧化钛纳米管对兔胫骨内种植体旋转扭力的影响

目的　通过兔子动物模型评估种植体表面不同管径的TIO2纳米管对成骨细胞黏附、种植体扭力和成骨基因表达的影响。方法　将24个订做的螺旋状的长为6 mm,外径为2.5 mm的纯钛种植体分为3组。A组：对照组平滑面种植体;B组：表面为30 nm管径TiO2纳米管的种植体;C组：表面为70 nm管径TiO2纳米管的种植体。分别将种植体植入兔子胫骨,手术后四周,处死兔子,采用数字扭力仪通过反向旋转取下腿部种植体,测量种植体扭力,通过扫描电子显微镜分析种植体表面成骨细胞的粘附,通过实时PCR检测核心结合因子（Runx2）、胰岛素样生长因子（IGF）、I型胶原（col 1）和骨钙素（OCN）的基因表达水平。结果　表面为70 nm管径TiO2纳米管的种植体可以增强兔胫骨内种植体的扭力（P＜0.05）,并显著性的提高Runx2、IGF、col 1和 OCN等成骨基因的表达水平（P＜0.05）。结论　相对于30 nm管径纳米管,表面为70 nm管径纳米管的种植体可以获得良好的成骨反应,并且在早期植入期具有较高的界面强度。     

Peri-implant hard and soft tissue integration to dental implants made of titanium and gold

OBJECTIVES: The aim of the study is to compare the peri-implant hard and soft tissue integration around dental implants made of commercially pure (c.p.) titanium or a gold alloy but with the same shape and surface roughness. MATERIAL AND METHODS: In four beagle dogs, all mandibular premolars were extracted. Three months later, four experimental non-submerged implants were placed in each edentulous premolar region. Each implant comprised three different zones: zone A (coronal), zone B (central) and zone C (apical). Each zone was made of either c.p. titanium or a gold alloy. Four different combinations of metal and zone were used. A plaque control program was initiated and 6 months later, the animals were sacrificed and biopsies were obtained. The biopsies including the implant and the surrounding tissues were processed for ground sectioning. RESULTS: The height of the peri-implant mucosa and the length of the barrier epithelium were similar at the four experimental sites. The marginal bone level in the different metal combinations was located between 4.5 and 4.8 mm apical of the implant rim. The percent of mineralized bone that was in direct contact with the implant surface (BIC%) was consistently greater in the marginal than in the apical portion of the implants. The BIC% for the marginal and apical zone were consistently greater for implant portions made of titanium than for portions made of gold alloy (zone B: 42.7% vs. 36.5%, zone C: 33.2% vs. 19%). CONCLUSIONS: Osseointegration was achieved to surfaces made of both c.p. titanium and a gold alloy. BIC% was higher at titanium than at gold surfaces. Moreover, the peri-implant soft tissue dimensions were not influenced by the metal used in the 'marginal' zone of the implant.     

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.     

Soft Tissue Attachment to Titanium Implants Coated with Growth Factors

Background: Enhancing the connective tissue seal around dental implants may be an important factor in implant survival. Purpose: The objective of the study was to investigate the effect of implant surface modification with either platelet‐derived growth factor (PDGF) or enamel matrix derivative (EMD) on connective tissue attachment to titanium implants. Materials and Methods: Eighteen implants (Branemark® Mk III Groovy NP (3.3 mmØ × 10 mm, Nobel Biocare) were implanted subcutaneously into 12 rats. Six implants each were coated with either PDGF or EMD immediately prior to implantation and six implants were left uncoated. Implants were retrieved at 4 and 8 weeks and assessed histologically to compare the soft tissue adaptation to the implant surfaces. Results: Ingrowth by soft connective tissue into the threads of all implants was noted at 4 and 8 weeks. Coating with growth factors did not alter the orientation of fibroblasts and collagen fibers. The depth of connective tissue penetration into the implant grooves was significantly greater for the implants coated with PDGF at 4 weeks. The thickness of the connective tissue in growth was significantly less for the implants coated with PDGF at 8 weeks. Conclusion: Coating of the implant surface with rhPDGF‐BB or EMD can increase the speed and quantity of soft tissue healing around the implant surface.     

非埋入式种植体术后早期IL-1与种植体周软硬组织的关系

目的：探讨种植术后种植体周软组织渗出液中白细胞介素-1（IL—1）的含量变化及其与软组织愈合、种植体周早期边缘骨吸收的关系。方法：33名患者植入非埋入式ITI系统种植体54颗。种植术后及1月时拍摄曲面断层片。测量术后1月时种植体边缘骨变化量。4天、10天时对种植体周渗出液中IL-1进行ELISA法检测,检测相同时间内种植体周IL-1的含量,并观察软组织的愈合情况。结果：10天时软组织与种植体的贴合情况比4天时好（P〈0．01）;4天,10天时IL-1的含量与软组织和种植体的贴合不良呈正相关,4天r=0．543,P〈0．01,10天r=0．553,P〈0．01;10天时IL-1含量显著低于4天时（P〈0．01）;早期IL-1的含量与1月时种植体早期边缘骨吸收呈正相关,4天r=-0．632,P〈0．01,10天r=0．496,p〈0．01。结论：随着伤口愈合,IL-1含量降低,软组织一种植体的贴合情况变好。IL-1可以反映软组织的愈合情况。术后种植体周龈沟液内IL—1的含量影响种植体早期边缘骨吸收。     

Loaded custom-made zirconia and titanium implants show similar osseointegration: an animal experiment

BACKGROUND: Zirconia might be an alternative material to titanium for dental implant fabrication. The aim of the present study was to investigate the histological behavior (osseointegration) of loaded zirconia implants in an animal model and to compare it with the behavior of titanium implants. METHODS: Five months after extraction of the upper anterior teeth, 12 custom-made titanium implants (control group) and 12 custom-made zirconia implants (test group) were inserted in the extraction sites in six monkeys. Before insertion, the titanium implant surfaces were sandblasted with Al2O3 and subsequently acid-etched. The zirconia implants were only sandblasted. Six months following implant insertion, impressions were taken for the fabrication of single crowns. A further 3 months later, nonprecious metal crowns were inserted. Five months after insertion of the crowns, the implants with the surrounding hard and soft tissues were harvested, histologically prepared, and evaluated under the light microscope regarding the peri-implant soft tissue dimensions and mineralized bone-to-implant contact. RESULTS: No implant was lost during the investigational period. The mean height of the soft peri-implant tissue cuff was 5 mm around the titanium implants and 4.5 mm around the zirconia implants. No statistically significant differences were found in the extent of the different soft tissue compartments. The mean mineralized bone-to-implant contact after 9 months of healing and 5 months of loading amounted to 72.9% (SD: 14%) for the titanium implants and to 67.4% (SD: 17%) for the zirconia implants. There was no statistically significant difference between the different implant materials. CONCLUSION: Within the limits of this animal experiment, it can be concluded that the custom-made zirconia implants osseointegrated to the same extent as custom-made titanium control implants and show the same peri-implant soft tissue dimensions.     

Histologic comparison of ceramic and titanium implants in cats

This study compared the reparative processes around cylindrical glass-ceramic-coated and pure titanium implants placed in feline femurs. Six weeks after implant placement, bone specimens with inserted implants were prepared for histologic examination including histomorphometric quantification of the relative implant surface areas that were in contact with bone. The glass-ceramic implants were surrounded by a 0.2- to 0.5-mm envelope of fibrous connective tissue [corrected]. By contrast, the major part of the titanium implants (81% +/- 5%) was in direct contact with living lamellar or woven bone. Thus, titanium and glass ceramic evoked different reparative processes when implanted in bone, and only the titanium implants appeared to become osseointegrated.     

Soft tissue integration versus early biofilm formation on different dental implant materials

Objective

Dental implants anchor in bone through a tight fit and osseo-integratable properties of the implant surfaces, while a protective soft tissue seal around the implants neck is needed to prevent bacterial destruction of the bone-implant interface. This tissue seal needs to form in the unsterile, oral environment. We aim to identify surface properties of dental implant materials (titanium, titanium-zirconium alloy and zirconium-oxides) that determine the outcome of this “race-for-the-surface” between human-gingival-fibroblasts and different supra-gingival bacterial strains.

Methods

Biofilms of three streptococcal species or a Staphylococcus aureus strain were grown in mono-cultures on the different implant materials in a parallel-plate-flow-chamber and their biovolume evaluated using confocal-scanning-laser-microscopy. Similarly, adhesion, spreading and growth of human-gingival-fibroblasts were evaluated. Co-culture experiments with bacteria and human-gingival-fibroblasts were carried out to evaluate tissue interaction with bacterially contaminated implant surfaces. Implant surfaces were characterized by their hydrophobicity, roughness and elemental composition.

Results

Biofilm formation occurred on all implant materials, and neither roughness nor hydrophobicity had a decisive influence on biofilm formation. Zirconium-oxide attracted most biofilm. All implant materials were covered by human-gingival-fibroblasts for 80–90% of their surface areas. Human-gingival-fibroblasts lost the race-for-the-surface against all bacterial strains on nearly all implant materials, except on the smoothest titanium variants.

Significance

Smooth titanium implant surfaces provide the best opportunities for a soft tissue seal to form on bacterially contaminated implant surfaces. This conclusion could only be reached in co-culture studies and coincides with the results from the few clinical studies carried out to this end.     

纯钛种植体激光-微弧氧化表面处理对早期骨结合的影响

目的:对比机械光滑表面和经激光-微弧氧化处理表面的纯钛种植体的理化性能,及其对早期骨结合的影响。方法:将纯钛棒加工制作成16颗螺纹柱形种植体,对照组(光滑组)为机械加工光滑表面种植体8颗,实验组(激光-微弧氧化组)为经激光-微弧氧化处理种植体8颗。通过能谱分析仪(EDX)和扫描电镜(SEM)分析种植体表面性质,Veeco粗糙仪检测其粗糙度(Ra)。分别将16颗种植体随机植入新西兰兔的胫骨,4周后处死取样,处死前第13天和第14天皮下注射四环素,处死前第3和第4天皮下注射钙黄绿素,通过四环素-钙黄绿素双色标记示踪检测其矿化速率。将标本通过塑料包埋制作成不脱钙含种植体骨切片,观察种植体-骨界面的骨结合情况。结果:实验组表面可见较大级别微孔,基本与激光处理后一致,孔径约100μm,孔深40⁸0μm。种植体表面微弧氧化膜具有多微孔结构,微孔孔径约180μm。种植体表面微弧氧化膜具有多微孔结构,微孔孔径约1⁵μm,微孔内还可见更小级别微孔,孔径小于1μm。对照组种植体表面Ra值为0.179μm,实验组表面的微弧氧化膜Ra值为1.55μm。对照组只检测到Ti元素,实验组钛表面氧化膜层中含Ti、O、Ca、P元素。实验组的矿化速率和种植体与骨接触的百分率(OI值)均显著高于对照组(P<0.05)。结论:通过激光-微弧氧化表面处理,纯钛种植体表面形成多层次多微孔的微弧氧化膜,具有良好的生物相容性和骨引导性,能促进种植体骨结合。