钛片表面粗糙度和氧化膜对成骨细胞黏附影响的体外研究

目的 研究钛片表面粗糙度和氧化膜对成骨细胞黏附的影响,为选择临床种植体的表面处理方法提供依据.方法 250片纯钛钛片分为5组.采用直径分别为108～130 μm(S<,1>组)、216～301 μm(S<,2>组)、356～411 μm(S<,3>组)TiO<,2>砂对钛片表面进行喷砂处理:另外一组钛片采用钛浆喷涂(T...     

添加纳米二氧化钛树脂基托材料抗菌性能的研究

目的：研究纳米二氧化钛树脂基托在体外对变形链球菌和白色念珠菌的抗菌效果。方法：在聚甲基丙烯酸甲酯基托树脂粉中添加以1％,3％,5％不同比例的纳米二氧化钛抗菌剂,制成树脂基托。采用薄膜密着法,分别测试添加抗菌成分后,树脂基托对变形链球菌和白色念珠菌的抗菌活性。测定纳米二氧化钛对变形链球菌和白色念珠菌的最小抑菌浓度,测含3种不同比例的二氧化钛抑菌浓度。结果：采用薄膜密着法对抗菌效果进行测试,对变形链球菌的抗菌率分别为：64．9％,93．2％,97．3％,对白色念珠菌的抗菌率分别为：66．2％,95．4％,100％。采用时效法测试时间长短对材料的影响,结果显示时间对材料无统计学差异。光照法对树脂材料测试在紫外光线下变形链球菌、白色念珠菌抗菌率均达100％,变形链球菌强光下达到98％,白色念珠菌达99％。变形链球菌自然光线下达到95％,白色念珠菌达97％。变形链球菌暗环境下达到93％,白色念珠菌达95％。结论：树脂基托在体外表现了一定的抗变形链球菌和抗白色念珠菌的效果,当树脂基托中抗菌剂的浓度达到3％时,即可达到满意抗菌效果。采用薄膜密着法对进行抗菌性能的评价具有可行性。     

Effect of titanium dioxide nanoparticle reinforcement on flexural strength of denture base resin: A systematic review and meta-analysis

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Adhesion of periodontal bacteria to titanium, and titanium alloy powders

In this study, the adhesion of radioactively labeled Actinomyces viscosus (A.viscous), Actinobacillus actinomicetemcomitans (Aa) and Porphyomonas gingivalis (P gingivalis) to titanium (Ti) and Ti₆Al₄V alloy (Ti‐alloy) coated with albumin or human saliva was investigated. All the tested bacteria displayed greater attachment to Ti‐alloy than to Ti. P. gingivalis exhibited less adhesion to Ti and Ti‐alloy than did the other bacterial strains. Adhesion of A. viscosus and Aa was greatly reduced when Ti or Ti‐alloy were coated with albumin or saliva. P. gingivalis demonstrated a lesser reduction in adhesion to albumin or saliva‐coated surfaces. The results show that oral bacteria have different adhesion ffinities for Ti and Ti‐alloy and that both albumin and human saliva reduce bacterial adhesion.     

钛网成型复合自体颗粒骨移植修复下颌骨缺损动物实验的组织学研究

目的研究钛网成型复合自体颗粒骨移植重建下颌骨节段性缺损的组织学变化。方法5只Beagle犬,每只动物一侧下颌骨制备长3.5cm的节段性缺损。用钛网成型重建下颌骨外形,钛钉固定。将切除的下颌骨块和髂骨剪成直径约2mm颗粒,将皮质骨和松质骨混合(按体积比约为3:1),并紧密充填在钛网内。术后6个月取移植骨做组织学检查,包括HE染色、硬组织切片荧光观察和Van-Gieson染色。结果移植骨的表层由多层平行排列的板层骨构成,板层骨皮质骨较薄,孔隙较多。板层骨下方移植骨内部呈现为众多粗大的小梁骨相互融合成网状结构,网状结构内部可见大量排列有序较致密的骨单位。结论钛网成型自体颗粒骨移植能够形成良好的骨组织学结构,有利于种植体植入,修复下颌骨节段性缺损的咬合功能。     

舌神经修复效果及评价方法的初步研究

本研究目的是评价舌神经吻合后舌前２／３感觉和味觉恢复的情况。应用神经外膜吻合修复舌神经损伤１４例，初步研究结果表明：①舌神经重度损伤后，患侧舌前２／３菌状乳头大多萎缩、消失，感觉和味觉严重障碍；②神经外膜吻合修复舌神经，菌状乳头可以再生，术后一年，５０％患者感觉恢复正常，３５．７１％患者味觉恢复正常；③感觉功能检查、味觉功能测定、菌状乳头及其味孔定量观察评价舌神经的损伤和修复，结果是客观、准确、可靠的。     

Influence of initial implant mobility on the integration of titanium implants. An experimental study in rabbits.

In the present study, the influence of initial instability on the healing of titanium implants was studied in 9 lop‐eared rabbits. Titanium implants (Brånemark System®) were inserted in the tibiae, a location with cortical bone only, in such a way that they were either stable (control), rotation‐mobile, or totally mobile. Implants were also inserted in the distal femoral condyles, representing an implantation bed with mainly cancellous bone, so they either showed no initial mobility (control) or were rotation‐mobile. After 12 weeks of healing, the implants were retrieved, together with surrounding bone, fixed, dehydrated, and embedded in plastic resin. About 10 μm thick ground sections were prepared for light microscopic morphometry. The mineralized bone to titanium contact, and the amount of bone occupying the threads, were calculated, whereafter the outcome of the different locations were compared. All retrieved implants were clinically stable at the end of the experiment. For the tibia sites, a statistically significant less bone to titanium contact, and a less amount of bone in the threads, were found for the totally mobile implants, as compared to the corresponding initially stable controls. Moreover, a statistically significant higher amount of bone was found in the threads of the rotation‐mobile implants inserted in the femoral condyle as compared to their initially stable controls. The study indicated that initial rotation‐mobility. independent if it occurs in cortical or trabecular bone, does not necessarily lead to an inferior integration of unloaded implants. However, initial total implant mobility within the cortical layer results in a statistically significant less amount of lb one around the implants, as compared to stable controls.     

激光焊接对钛耐应力腐蚀性能影响的实验研究

目的研究激光焊接对钛耐应力腐蚀性能的影响。方法将实验组激光焊接铸钛试样焊缝区加载后浸入37℃人工唾液中,浸泡90 d。实验前、后用电子扫描电镜观察焊接试样熔区表面形貌。在万能材料实验机上作拉伸实验,测出拉伸负荷,计算抗张强度,将结果进行统计学分析。不进行应力腐蚀试验的激光焊接铸钛试样作为对照组。结果应力腐蚀试验后,激光焊接钛试件表面无变色,扫描电镜观察无腐蚀裂纹及腐蚀产物,实验组抗张强度为(657.06±54.04)MPa与对照组(609.81±37.24)MPa相比差异无显著性(P>0.05)。结论激光焊接对钛的耐应力腐蚀性能无影响。     

Bone-tissue formation and integration of titanium implants: an evaluation with newly developed enzyme and immunohistochemical techniques

Background: Examination of the tissue surrounding retrieved implants involve routine investigations on cut and ground sections. Undecalcified sections with implants in situ are histologically stained followed by qualitative and quantitative observations of the tissue response to the implants by light microscopy. Purpose: A novel technique that allows for the accurate definition and quantification of enzymes involved in bone formation (alkaline phosphatase) and resorption (acid phosphatase) in the tissue is presented. Materials and Methods: Commercially pure titanium and titanium alloy (Ti6A14V) implants were retrieved after 6 and 12 weeks of healing in rabbit bone. In addition, 4-week specimens from commercially pure titanium bone harvest chambers placed in rabbit bone were used. Undecalcified cut and ground sections were produced and evaluated with enzyme and immunohistochemical staining techniques. Results: The titanium implants retrieved after 6 weeks of insertion in rabbit bone revealed a higher activity of both alkaline phosphatase and acid phosphatase activity compared to the implants followed for 12 months. The former samples revealed ongoing bone-tissue remodeling in the interface, whereas the latter ones showed steady-state bone conditions. Applying the new technique allowed for investigation of various bone proteins present in the tissue that had formed inside titanium canals of harvest chambers at various times of follow-up. Conclusions: The combination of routine histologic stainings with enzyme and immunohistochemical technique of cut and ground specimens is a valuable tool in the investigations of retrieved implants from humans and animals. This novel technique now may be used to describe the state of bone regeneration in the interface zone associated with implant research.     

钛表面3种不同处理方法对钛-瓷结合影响的对比研究

目的对比钛表面分别经微弧氧化和Nd:YAG激光处理、喷砂处理后的表面形貌、理化性能的差异,比较其对钛瓷结合强度的影响。方法将60个规格为25.0 mm×5.0 mm×0.5 mm的标准钛片试件,随机均分为3组,每组20片(A组为微弧氧化组,B组为激光轰击组,C组为喷砂组),运用扫描电镜、X射线衍射仪、EDS等分析其形貌和物相;三点弯曲实验测试钛瓷结合强度并进行统计学分析比较。结果 A、B、C 3组试件的钛瓷结合强度均高于ISO9693要求的25 MPa,Nd:YAG激光处理试件钛瓷结合强度较微弧氧化处理高,且两者均高于喷砂组。结论 3种处理方式都能提高钛表面的钛瓷结合强度,Nd:YAG激光处理后效果优于微弧氧化和喷砂处理。     

高脂血症对钛种植体骨结合影响的研究进展

高脂血症是常见的全身代谢性疾病,中老年人多见,发病率较高。高脂血症是种植治疗的风险因素之一,可引起种植体骨结合不良,从而影响种植义齿的临床疗效。本文针对高脂血症对钛种植体骨结合影响的研究进展作一综述。     

Neural response to sandblasted/acid-etched, TiO-blasted, polished, and mechanochemically polished/nanostructured titanium implant surfaces

The purpose of this study was to explore morphologic, functional, and behavioral effects of rough (sandblasted-large grid/acid-etched (SLA) and TiO2 blasted), mechanically polished, and mechanochemically polished titanium implant surfaces on nerves. The compound action potentials (cAPs) of sciatic nerves of sacrificed Wistar rats (n=10) were quantified at the in vitro level, while contacting disk-shaped test specimens. The test specimens were also implanted directly on the sciatic nerves of another group of animals (n=33), hot-plate tests were undertaken for 10 consecutive days, and then the animals were sacrificed. Quantification of signal transduction speeds and cAPs of the nerves of these animals were undertaken at the in vitro level. Finally, the nerves were processed for histologic analysis. The signal transduction speeds and duration of cAPs of all groups were similar (P>0.05), whereas the amplitudes of cAPs of nerves contacting SLA implants were higher than those of TiO2 blasted and mechanochemically polished surfaces (P<0.05). Response latencies of nerves contacting mechanically polished specimens were slightly higher than the other groups (P>0.05). Histologic evaluations did not reveal any signs of adverse tissue response adjacent to specimens tested. Rough and polished titanium implant surfaces lead to similar neural response in vivo and in vitro that fall into physiologic limits.     

Histomorphometry and micro-computed tomography of bone augmentation under a titanium membrane

OBJECTIVES: Bone augmentation underneath an occlusive titanium membrane is evaluated in most cases by means of serial histological sections and histomorphometry. Micro-computed tomography (micro-CT) is a less invasive and dynamic technique to measure bone volume in animals of a size that fits into the gantry. The aim of the present study was to evaluate whether the latter approach could match histomorphometry to assess bone augmentation under a titanium membrane. MATERIAL AND METHODS: Pre-formed titanium cups were placed on the skull of 16 rabbits. Bone formation underneath the cups was allowed to occur for 12 weeks. The amount of bone volume assessed by micro-CT was expressed as a numerical unit. One unit volume corresponds to 0.043 mm3. The measurements reveal the volume of bone-like tissue under the membrane, with the same density as that of the original rabbit skull bone. Histological sections were cut along the same plane as the one used for the micro-CT images. The total bone surface was assessed by a digital image system in double-stained undecalcified histological sections and related to the maximum available surface of the titanium cups, which was on average 1366 mm2. RESULTS: The amount of total bone surface found under the titanium membrane varied between 40 and 163 mm2. Measured by micro-CT, the bone detected ranged from 3.7 to 396 numerical units. A highly significant (P<0.001) correlation was found between the total bone volume measured in conventional serial histological sections and by the micro-CT technique (r2=0.72). CONCLUSIONS: The total bone volume measured underneath a membrane using the micro-CT when compared with histological sections remained within a 16% error. This is because of the scattering effect of the metallic membrane and the impossibility to distinguish newly formed bone from the original skull bone on the micro-CT images.     

Evaluations of bone tissue integration to pure and alloyed titanium implants

Purpose: This study was performed for comparisons of tissue integration to commercially pure (CP) and titanium-6-aluminum-4 vanadium (Ti-6-Al-4V) implants using various existing three-dimensional biomechanical and two-dimensional histomorphometrical techniques, and to monitor the loosening torque during in vivo removal torque (RTQ) test with a novel unit not used before in a pilot study in rabbits.
Materials and Methods: The implants were topographically characterized and inserted in femurs and tibiae of five rabbits (in total 40 implants, 20 per group). After 16 weeks, the implant integration was biomechanically evaluated by: (1) resonance frequency test, and (2) peak RTQ test and the graph from the monitoring curve. Biopsies of the implants in situ were processed to undecalcified cut and ground sections followed by light microscopical quantifications. Shear strength calculations were performed.
Results: Significantly higher mean value of RTQ ( p  = .01) and shear strength tests ( p  = .03) were observed for the CP titanium implants compared to Ti-6-Al-4V implants. The monitoring curve from the RTQ test demonstrated no differences in the shape or form that could provide further information about the differences in the implant-to-bone attachment.
Conclusions: The CP titanium implants showed increased RTQ and shear strength values compared to the Ti-6-Al-4V implants. The new tool of monitoring the RTQ curve could not demonstrate differences between the two materials. The exact influence of the implant materials on the surrounding tissues needs to be further investigated.     

Adhesive bonding of titanium with a thione-phosphate dual functional primer and self-curing luting agents

A consistent bond between the metal framework and the luting agent is desired when resin-bonded prostheses are constructed with titanium. The purpose of this study was to evaluate three different metal primers on titanium bonding. Two sources of titanium (machined 99.9% titanium and cast Titan Ingot JS2) were used. Disk specimens were bonded with eight combinations of three primers and two luting agents (Panavia 21 and Super-Bond C&B), including two controls. Shear bond strengths were determined after 24-h water storage and after 10,000 cycles of thermocycling. Bond strengths were influenced by thermocycling, primer, luting agent and their combinations, but no significant differences were found between the machined 99.9% titanium and the cast ingot. The thione-phosphate dual functional primer (Alloy Primer) was comparable to the phosphate primer (Cesead II Opaque Primer) and the thiophosphate primer (Metal Primer II) for bonding the titanium metals examined. The most durable bond was obtained in three combinations of these primers and one luting agent (Super-Bond C&B).     

等离子渗氮后纯钛的耐磨性能的研究

目的:模拟口腔环境,研究在牙刷磨耗机的磨擦下,等离子渗氮对纯钛的耐磨性能的影响。方法:铸造纯钛试件24片,随机分为0.2%NaF渗氮组、0.2%NaF未渗氮组、人工唾液渗氮组、人工唾液未渗氮组,在牙刷磨耗机上刷洗75 000次,对比刷洗前后的粗糙度Ra增加值及色彩变化,并在扫描电镜下观察试件表面形貌。结果:与未渗氮组比较,0.2%NaF等离子渗氮后纯钛的表面粗糙度Ra增加值及色彩变化差异均有显著性(P<0.05);不同混合液比较,0.2%NaF溶液对试件的耐磨性能影响较人工唾液的影响大(P<0.05)。SEM观察表明:在0.2%NaF溶液中刷洗后未渗氮组纯钛试件表面磨耗现象严重。结论:等离子渗氮后纯钛的耐磨性能得到提高;含氟溶液能降低纯钛表面的耐磨性能。     

The soft tissue response to contaminated and cleaned titanium surfaces using CO2 laser, citric acid and hydrogen peroxide. An experimental study in the rat abdominal wall

The soft tissue response to clinically retrieved and decontaminated cover screws was evaluated in a rat model. The cover screws were cleaned by using citric acid, sterile water, hydrogen peroxide and CO2 laser alone or with a combination of these. In addition, decontaminated but not cleaned and unused cover screws were used as negative and positive controls, respectively. After cleaning the cover screws were implanted in the abdominal wall of the rat for 6 weeks. The thickness of the fibrous capsule and the number of macrophages within the capsule were measured by means of light microscopical morphometry. As compared to the negative control, CO2 laser on dry surface, CO2 laser + hydrogen peroxide and the positive control had statistically significant thinner fibrous capsules. As compared to the positive, only laser alone resulted in a similar tissue response. It is concluded that CO2 laser used alone or in combination with hydrogen peroxide may be used clinically for sufficient decontamination of titanium surfaces.     

The nociceptive and anti-nociceptive effects of white mineral trioxide aggregate

Aim  To assess the nociceptive and antinociceptive effects of white mineral trioxide aggregate (WMTA) using the orofacial formalin test in rats.
Methodology  Rats ( n  = 10 in each group) were separately injected into the ipsilateral upper lip with either 40 μL of a 2.5% formalin solution and eugenol (50 mg kg⁻¹) or WMTA (5, 10 and 20 mg dissolved in 0.2 mL saline) alone. In a second experiment to evaluate antinociception effects, 15 min prior to formalin injection, rats were pre-treated with either white ProRoot MTA (20 mg dissolved in 0.2 mL saline) or eugenol. The time each rat spent rubbing the injected site with its paw, as an index of nociception, was recorded for a period of 45 min.
Results  Administration of 40 μL white ProRoot MTA (5, 10 and 20 mg per 0.2 mL) alone did not produce any significant nociceptive response. Moreover, prior treatment with WMTA caused significant ( P  < 0.001) inhibition of formalin-induced nociception. Injection of eugenol (50 mg kg⁻¹) provoked the first phase of a nociceptive response, although its intensity was reduced compared with that produced by formalin. Pre-treatment with eugenol significantly ( P  < 0.0001) inhibited the induction of nociception by formalin. Comparison of the behavioural responses observed in WMTA and eugenol-treated rats alone or in combination with formalin revealed that WMTA did not only induce pain behaviour but also prevented formalin-induced nociception.
Conclusion  White mineral trioxide aggregate, when compared with eugenol, was more effective in treating nociceptive pain in the orofacial formalin test.