4种临床用烤瓷合金材料细胞毒性研究

目的　选择 4种临床用烤瓷合金 ,对其细胞毒性进行检测和比较。方法　采用四甲基偶氮唑蓝比色法 (MTT法 )检测乳酸脱氢酶活性来测定合金析出离子对体外培养细胞的影响 ,比较不同合金对细胞增殖的作用 ,评定 4种烤瓷合金的毒性作用。结果　镍铬烤瓷合金抑制细胞增殖最明显 ,含钛的镍铬烤瓷合金、钴铬烤瓷合金次之 ,金合金基本不影响细胞增殖。结论　应根据临床情况和合金细胞毒性情况合理选用烤瓷合金材料     

镍铬合金烤瓷冠修复后的离子析出状况及研究方法

镍铬合金是常用的口腔修复材料,由于口腔唾液中含有众多离子,易造成镍铬合金的电化学腐蚀,析出金属离子,引发过敏和毒性反应。因此检测镍铬合金在人工唾液和生物液体中的离子成分和浓度可评价镍铬合金的生物相容性。本文综述了镍铬合金烤瓷冠的电化学腐蚀行为、析出的金属离子所造成的致敏和毒性反应以及光谱分析法在检测金属离子方面的研究和应用。     

牙科铸造合金诱发慢性毒副作用细胞机制的研究进展

牙科铸造合金在口腔临床中被广泛应用，而合金修复后在长期使用过程中，由于口腔内复杂微环境的影响，合金在口腔中的腐蚀会引起金属离子析出。大量的研究发现：这些析出的金属离子会对邻近的组织和细胞带来不同程度的慢性毒副作用，主要包括局部不良反应和全身不良反应。由于全身不良反应的发生率较低，相关的数据报道也比较有限，所以对合金中析出的金属离子引起的口腔局部不良反应成为国内外学者研究的热点。本文就铸造合金析出的金属离子对组织和细胞的毒副作用的研究现状及相应的细胞调控机制作一综述。     

五种全冠合金铸造后的腐蚀性研究

目的 测定五种制作全冠的合金铸造后在体外细胞培养液中析出金属离子的种类及不同时间段析出的各种金属离子的量。方法 本实验用电感藕荷等离子质谱仪（ICP－MS）定量测定金属离子测试。结果 镍铬合金和钴铬合金析出离子最多银钯合金和钯合金有一定的金属离子析出，纯钛只析出微量钛离子。结论 纯钛、钯合金的耐腐蚀性最好，银钯合金次之，镍铬合金和钴铬合金的耐腐蚀性较差。     

五种烤瓷合金在人工唾液中的离子析出研究

目的 通过测定镍铬合金、镀金镍铬合金、涂金泥镍铬合金、钛合金和金钯合金5种烤瓷合金在人工唾液中,连续时间段内析出金属离子的种类和数量,为各类合金耐腐蚀性能的比较提供一定的实验依据.方法 将各类合金制作的试件分别浸泡于ISO/TR10271标准唾液(37℃,pH=6)的实验介质中,运用原子吸收光谱分析仪在连续时间段内测定各类合金试件浸泡液中析出金属离子的种类和数量.结果 钛合金离子析出量最多,但其中未检测出Ti;镀金镍铬合金和涂金泥镍铬合金离子析出量次之,镍铬合金离子析出量居第三,金钯合金离子析出量最少.结论 金钯合金的离子析出量相对较少,耐腐蚀性能相对较好;镀金和涂金泥技术对镍铬合金的耐腐蚀性能未见显著改善;钛合金的离子析出量较镍铬合金还多,其耐腐蚀性能尚不够理想.     

牙科合金材料的生物相容性及影响合金离子析出的因素

牙科合金因其理想的物理机械性能运用于临床已有几十年的历史,大量的体内、外实验均认为合金材料制作的义齿戴入口内后,释放的金属离子可能诱发口腔炎症,存在基因突变和致癌性等潜在危害。本文旨在对常用牙科合金材料的生物相容性及影响合金离子析出的因素作一综述。     

齿科合金体外培养液中离子析出浓度与细胞凋亡相关基因关系的探讨

目的探讨齿科合金体外培养液中离子析出浓度与细胞凋亡相关基因的关系。方法将不同齿科合金在RPMI1640培养液中制成不同时间点的浸提液,用ICP-MS方法检测浸提液中的离子析出浓度。将5种金属合金浸提液及阴性对照与L929细胞培养48h,用RT-PCR方法检测细胞caspase-3、caspase-8和caspase-9的mRNA表达。结果合金浸提液及阴性对照培养的L929细胞的caspase-8mRNA无明显差异,caspase-3和caspase-9mRNA差异显著,由低到高依次为阴性对照组〈金合金组〈钴铬合金组〈银钯合金组〈镍铬合金组。结论不同齿科合金中的金属离子都会不同程度地诱导细胞凋亡,且其凋亡途径为线粒体途径。     

齿科常用金属合金的腐蚀及细胞毒性研究进展

在齿科的临床治疗中,金属合金常用于牙体及牙列缺损的修复。在口腔复杂的环境中,金属易发生电化学腐蚀,析出金属离子。这些金属离子会在局部或全身分布,引起局部或全身的过敏反应。体内外实验已发现金属离子会造成细胞DNA的损伤,导致细胞因子释放的增加。但是,金属离子的细胞毒性反应机制目前尚没有充分的研究来证实。本文对导致齿科金属腐蚀的因素和细胞毒性的研究进展做一综述。     

五种烤瓷合金在人工唾液中的离子析出研究

目的研究5种烤瓷合金的耐腐蚀性能。方法将镍铬合金、镀金镍铬合金、涂金泥镍铬合金、钛合金和金钯合金制作的试件分别浸泡于ISO/TR10271标准唾液(37℃,pH=6)的人工唾液实验介质中,应用原子吸收光谱分析仪测定连续时间段内浸泡液中析出金属离子的种类、数量和浓度。结果钛合金离子析出最多,镀金镍铬合金和涂金泥镍铬合金离子析出较多,镍铬合金离子析出持续稳定,金钯合金离子析出最少。各类合金表面代表元素以其主要组成元素为主,在浸泡腐蚀液中均未发生显著改变,其中钛合金并未检测出钛离子。结论金钯合金的耐腐蚀性能最好,镀金和涂金泥技术对镍铬合金的耐腐蚀性能没有显著改善,钛合金的耐腐蚀性能与镍铬合金相比也并无优势。     

钯银合金细胞毒性的研究

目的:检测2种钯银合金的细胞毒性。方法:制作合金标准铸件,提取浸渍液后采用MTT法进行活细胞形态观察和吸光度值测定并转化为毒性级别,进行评价。结果:钯银合金浸渍液吸光度值显著高于镍铬合金,细胞毒性级别低于镍铬合金,细胞生长形态良好。结论:钯银合金细胞毒性低于镍铬合金。     

In vitro cytotoxicity of metallic ions released from dental alloys

The cytotoxicity of a dental alloy depends on, but is not limited to, the extent of its corrosion behavior. Individual ions may have effects on cell viability that are different from metals interacting within the alloy structure. We aimed to investigate the cytotoxicity of individual metal ions in concentrations similar to those reported to be released from Pd-based dental alloys on mouse fibroblast cells. Metal salts were used to prepare seven solutions (concentration range 100 ppm–1 ppb) of the transition metals, such as Ni(II), Pd(II), Cu(II), and Ag(I), and the metals, such as Ga(III), In(III), and Sn(II). Cytotoxicity on mouse fibroblasts L929 was evaluated using the MTT assay. Ni, Cu, and Ag are cytotoxic at 10 ppm, Pd and Ga at 100 ppm. Sn and In were not able to induce cytotoxicity at the tested concentrations. Transition metals were able to induce cytotoxic effects in concentrations similar to those reported to be released from Pd-based dental alloys. Ni, Cu, and Ag were the most cytotoxic followed by Pd and Ga; Sn and In were not cytotoxic. Cytotoxic reactions might be considered in the etiopathogenesis of clinically observed local adverse reactions.     

Effects of mechanical stress on cytotoxicity of cobalt-chromium alloys for denture base

The effects of metal ions and mechanical stress on cells were examined in vitro, to shed light on tissue response to metal prosthesis. Seven commercial base alloy plates, four Co-Cr alloys, one pure Ti, one Ni-Cu-Ga alloy and one Ni-Cr alloy for solder were used. Two kinds of static load, 5 gf/cm2 and 10 gf/cm2, were applied to three kinds of tissue culture cells, L-929, HEp-2 and Gin-1 cells, for 24 hours, and then the cells were incubated for 7 days under normal culture conditions. Cell recovery was evaluated by cell number and protein content. The amount of dissolved metal ions was measured by atomic absorption spectroscopy (Experiment 1). A concomitant study of cell culture with known amounts of Co, Cr, Ni was carried out, and cell recovery was examined (Experiment 2). Atomic absorption spectroscopy showed that dissolution of either Co or Cr from the alloys tested was extremely small. However, the maximum amount of Ni and Cu dissolved from Ni-Cu-Ga alloy and Ni-Cr alloy for solder was over 10 ppm. Ti was not dissolved from pure Ti. Four Co-Cr alloys and pure Ti did not inhibit cell recovery or protein content with loading. However, Ni-Cu-Ga alloy and Ni-Cr alloy significantly inhibited cell recovery and protein content, and the effects were enhanced by loading. The cytotoxicity of Co, Cr or Ni ion at a static load of 10 gf/cm2 was higher than that at 5 gf/cm2. These results suggest that mechanical stress increases the cytotoxicity of dissolved metal ions.     

不同烤瓷合金材料诱导细胞DNA损伤与细胞凋亡的研究

目的研究不同牙科烤瓷合金材料诱导细胞DNA损伤与细胞凋亡的情况,评价各种烤瓷合金材料的生物相容性。方法选择镍铬合金、钛合金、钴铬合金和金合金四种牙科烤瓷合金材料,制备四种合金材料的浸提液,用浸提液培养L929细胞24h。分别采用单细胞凝胶电泳(彗星试验)和流式细胞技术检测细胞DNA损伤与细胞凋亡的情况。结果镍铬合金、钛合金、钴铬合金可诱导不同程度的细胞DNA损伤和细胞凋亡(P<0.05),而金合金与对照组间无统计学差异(P>0.05)。结论不同烤瓷合金材料诱导细胞DNA损伤和细胞凋亡的情况存在差异性。金合金是种生物相容性优越的牙科烤瓷合金材料。     

钴铬钼合金对L929细胞生物学行为的影响

目的：研究牙科用钴铬钼合金对L929细胞生物学行为的影响。方法：制备医用纯钛、钴铬钼合金、钴铬合金、镍铬合金的浸提液,在浸提液与L929细胞作用24 、48 、72 h后,用倒置相差显微镜观察细胞的生长情况,并通过CCK-8实验评定4种材料的细胞毒性;采用流式细胞仪Annexin V-FITC/PI 双染法评价材料对细胞凋亡的影响;应用吖啶橙染色法检测L929细胞在材料表面的黏附情况;采用SPSS17.0软件包对数据进行统计学分析。结果：倒置相差显微镜下观察,各时间点除镍铬合金组可见少量细胞核固缩,呈现轻微中毒状态外,其余3组细胞生长情况良好;钴铬钼合金组在各时间点的OD值、细胞凋亡率、细胞黏附数量均显著低于医用纯钛组(P<0.05),而高于钴铬合金组 (P<0.05)和镍铬合金组(P<0.05);观察期内,医用纯钛组、钴铬钼合金组、钴铬合金组细胞毒性均为1级,镍铬合金组为2级,表现为轻微毒性。结论：钴铬钼合金对L929细胞的生物学行为无明显不良影响,符合口腔生物材料的临床应用要求,具有良好的生物相容性。     

3种临床常用烤瓷合金对小鼠成纤维细胞L929的毒性评价

目的:评价3种临床常用牙科烤瓷合金材料的细胞毒性.方法:采用一种能快速评定细胞增殖率和细胞毒性的CCK-8比色法,检测镍铬合金(Ni,77.36%)、钴铬合金(Co,61.0%)、金合金(Au,58.0%)等3种烤瓷合金材料对小鼠成纤维细胞L929相对增殖率的影响;应用单细胞凝胶电泳(彗星电泳),检测3种烤瓷合金材料对小鼠成纤维细胞L929 DNA的损伤情况.采用SAS9.0软件包对数据进行统计学分析.结果:镍铬合金组、钴铬合金组和金合金组细胞的相对增殖率分别为(75.9510±7.6244)%、(84.8920±8.2660)%和(88.5420±12.3611)%.镍铬合金组的细胞毒性显著高于钴铬合金组(P＜0.05)和金合金组(P＜0.05),而钴铬合金组与金合金组之间无显著差异(P＞0.05),但3种材料的细胞毒性分级均为1级,表现为轻微毒性;镍铬合金组DNA损伤程度的彗星数目显著高于钴铬合金组(P＜0.05)和金合金组(P＜0.05).而钴铬合金组与金合金组无显著差异(P＞0.05).结论:钴铬烤瓷合金材料的细胞毒性显著低于镍铬烤瓷合金材料,而与58%金烤瓷合金材料的细胞毒性接近.临床上应尽可能选择钴铬烤瓷合金或58%金烤瓷合金等细胞毒性较低的烤瓷合金材料.     

Effects of chemical composition on the corrosion of dental alloys

The aim of this study was to determine the effect of the oral environment on the corrosion of dental alloys with different compositions, using electrochemical methods. The corrosion rates were obtained from the current-potential curves and electrochemical impedance spectroscopy (EIS). The effect of artificial saliva on the corrosion of dental alloys was dependent on alloy composition. Dissolution of the ions occurred in all tested dental alloys and the results were strongly dependent on the general alloy composition. Regarding the alloys containing nickel, the Ni-Cr and Ni-Cr-Ti alloys released 0.62 mg/L of Ni on average, while the Co-Cr dental alloy released ions between 0.01 and 0.03 mg/L of Co and Cr, respectively.The open-circuit potential stabilized at a higher level with lower deviation (standard deviation: Ni-Cr-6Ti = 32 mV/SCE and Co-Cr = 54 mV/SCE). The potenciodynamic curves of the dental alloys showed that the Ni-based dental alloy with >70 wt% of Ni had a similar curve and the Co-Cr dental alloy showed a low current density and hence a high resistance to corrosion compared with the Ni-based dental alloys. Some changes in microstructure were observed and this fact influenced the corrosion behavior for the alloys. The lower corrosion resistance also led to greater release of nickel ions to the medium. The quantity of Co ions released from the Co-Cr-Mo alloy was relatively small in the solutions. In addition, the quantity of Cr ions released into the artificial saliva from the Co-Cr alloy was lower than Cr release from the Ni-based dental alloys.     

4种牙科金属材料对成纤维细胞L929凋亡相关基因及蛋白表达的影响

目的 研究4种不同牙科金属材料（金合金、银钯合金、钴铬合金、镍铬合金）浸提液对小鼠成纤维细胞L929凋亡相关基因及蛋白表达的影响。方法 以金合金（A组）、银钯合金（B组）、钴铬合金（C组）、镍铬合金（D组）的浸提液体外培养小鼠成纤维细胞L929,并以含10%胎牛血清的RPMI1640培养基作为阴性对照（E组）。采用逆转录聚合酶链反应（RT-PCR）方法检测了4种牙科金属材料浸提液对L929细胞凋亡相关基因caspase-3、8、9 mRNA和蛋白表达的影响。结果 4种牙科金属材料浸提液培养小鼠L929细胞48 h后,除A组与E组间差异无统计学意义外,各组间caspase-3 mRNA及caspase-9 mRNA表达差异有统计学意义（P<0.05）。各组间caspase-8 mRNA差异无统计学意义。除A组与C组、B组与D组间差异无统计学意义外,caspase-3及caspase-9蛋白表达差异有统计学意义,各组间caspase-8蛋白差异无统计学意义。结论 4种牙科金属材料,除金合金外,均诱导小鼠成纤维细胞L929凋亡相关基因表达增加,金属离子可能通过线粒体通路诱导细胞凋亡。     

AlCoCrCuFeTix高熵合金细胞毒性评价及对L929细胞凋亡与Ⅰ型胶原合成的影响

目的　评价AlCoCrCuFeTix(x=0,0.25,0.5,1)系列高熵合金细胞毒性。方法　对AlCoCrCuFeTix(x=0,0.25,0.5,1)系列高熵合金进行MTT毒性实验评价其细胞毒性;流式细胞术AnnexinⅤ-FITC/PI双染法评价其对L929细胞凋亡影响;免疫荧光染色检测各组L929细胞Ⅰ型胶原的合成水平来评价该系列材料对细胞增殖的影响。结果　随着Ti元素的递增,AlCoCrCuFeTix(x=0,0.25,0.5,1)系列高熵合金细胞毒性增大,凋亡率呈上升趋势,而L929细胞的Ⅰ型胶原蛋白表达水平下降。实验表明AlCoCrCuFe此种金属具有良好的细胞相容性,细胞毒性各时间点评级均为1级,且凋亡率与Ⅰ型胶原蛋白表达水平与空白对照组无明显差异。结论　AlCoCrCuFeTix系列高熵合金中的AlCoCrCuFe具有良好的细胞相容性,可初步满足医疗器械使用的基本要求。     

The Effect of Bleaching Agents on the Surface Topography of Ceramometal Dental Alloys

Purpose: To study the effect of bleaching agents on the surface topography of ceramometal alloys. Materials and Methods: Three types of ceramometal alloys were used (gold, Ni‐Cr, Co‐Cr‐Ti), and two types of bleaching agents (an agent intended for home use, one intended for use in the dental office) were studied. Forty‐five specimens were constructed and divided according to the alloy type into three main groups, 15 specimens per group. Each group was further subdivided into three subgroups according to the type of bleaching agent used. The first subgroup (five specimens) was not subjected to any bleaching agent. The second and third subgroups were subjected to home and in‐office bleaching agents, respectively. Results: Au alloy showed the least surface roughness when subjected to either of the two bleaching agents. Ni‐Cr alloys showed the highest surface roughness for both the control and home bleached subgroups, and Co‐Cr‐Ti alloy showed the highest surface roughness in the in‐office bleached subgroup. No statistically significant difference was found between the control subgroup and the home‐bleached subgroup for either the Au alloy or the Co‐Cr‐Ti alloy. For the two alloys, both the control and home‐bleached subgroups were statistically different from the in‐office bleached subgroups. There was a statistically significant difference between the Ni‐Cr control subgroup and the other two bleached subgroups, while there was no difference between the two bleached subgroups. Results also showed that increasing the concentration of bleaching agents increased the surface roughness of all the tested alloys. There was a statistical difference between the Ni‐Cr alloy and the other two alloys in all tested subgroups except the in‐office bleached subgroup, for which no difference between the surface roughness of the Ni‐Cr alloy and the Co‐Cr‐Ti alloy was found. Scanning electron microscopic examination revealed surface deteriorations in the two bleached subgroups for all tested ceramometallic alloys. Conclusion: Surface topographic alterations occurred as a result of the application of bleaching agents. These alterations increased with the increase of the carbamide peroxide concentration.