K2O-Na2O-Al2O3-SiO2系统牙科微晶玻璃匹配氧化铝陶瓷的初步研究

目的:研究 K₂O-Na₂O-Al₂O₃-SiO₂系统牙科微晶玻璃匹配氧化铝陶瓷的热处理温度制度。方法:根据氧化铝陶瓷的热膨胀系数调整K₂O-Na₂O-Al₂O₃-SiO₂系统牙科微晶玻璃的原材料配比,利用K₂O-Na₂O-Al₂O₃-SiO₂系统牙科微晶玻璃的热处理温度制度形成微晶玻璃-氧化铝陶瓷复合材料;利用偏振光显微镜和X射线衍射分析仪观察样品的形态及显微结构特性,利用材料试验机测试材料的抗压强度。结果:经过原材料组份的调整,白榴石晶粒约1.0 μm、在玻璃基质中分布均匀;微晶玻璃-氧化铝陶瓷复合材料的抗压强度为500 MPa。结论:K₂O-Na₂O-Al₂O₃-SiO₂系统牙科微晶玻璃的热处理温度制度适合匹配氧化铝陶瓷。     

不同喷砂条件对选择性激光熔覆钴铬合金金瓷结合强度影响的研究

目的 研究不同的喷砂条件对选择性激光熔覆技术（SLM）制作的钴铬合金与瓷结合强度的影响。方法 用SLM技术制得63个10 mm×10 mm×2 mm钴铬合金试件块,随机分9组（n=7）,采用不同Al₂O₃粒度（A1=50 μm,A2=100 μm,A3=150 μm）和不同压强（B1=0.2 MPa,B2=0.4 MPa,B3=0.6 MPa）进行喷砂处理。每组随机选取一个试件进行扫描电子显微镜（SEM）观察,其余试件上瓷后用万能测试机测定试件的金瓷结合强度并观察其断裂模式,运用SPSS 17.0软件分析数据。结果 A1B1、A1B2、A1B3、A2B1、A2B2、A2B3、A3B1、A3B2、A3B3组剪切强度分别为（27.22±0.95）、（27.58±0.47）、（26.80±0.71）、（27.54±0.78）、（30.75±0.43）、（26.93±0.88）、（28.18±0.93）、（29.55±0.57）、（28.11±0.91） MPa。不同粒度Al₂O₃喷砂组间剪切强度的差异有统计学意义（P<0.05）,不同压强喷砂组间剪切强度的差异有统计学意义（P<0.05）,不同颗粒和不同压强对剪切强度的大小有交互作用（P<0.05）。剪切实验后,全部试件均为混合断裂模式。结论 在本实验条件下,SLM钴铬合金在0.4 MPa、100 μm的Al₂O₃颗粒喷砂后,金瓷结合强度最大。     

降钙素基因相关肽对MC3T3-E1成骨细胞氧化损伤的保护作用研究

目的 探讨降钙素基因相关肽（CGRP）对MC3T3-E1成骨细胞氧化损伤的保护作用及其潜在机制。方法1）构建细胞氧化损伤模型,将实验分为4组,H₂O₂组使用含不同浓度（10^-1、10^-2、10^-3、10^-4、10^-5 mol·L^-1）H₂O₂的培养液,CGRP+H₂O₂组使用含不同浓度（10^-6、10^-7、10^-8、10^-9、10^-10 mol·L^-1）CGRP的培养液预处理后再加入含10^-4 mol·L^-1 H₂O₂的培养液,对照组为常规培养液,空白组不接种细胞。培养12、24、36、48 h后,CCK-8法检测细胞增殖活性,筛选最佳建模浓度和CGRP对成骨细胞氧化损伤的最佳保护浓度。2）采用含10^-4 mol·L^-1 H₂O₂（H₂O₂组）、10^-8 mol·L^-1 CGRP（CGRP组）的培养液和10^-8 mol·L^-1 CGRP+10^-4 mol·L^-1 H₂O₂培养液（CGRP+H₂O₂组）、常规培养液（对照组）培养成骨细胞,测定超氧化物歧化酶（SOD）的活性、活性氧（ROS）的含量以及炎症因子肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1β、IL-6的水平。结果 1）在10^-4 mol·L^-1 H²O²时细胞增殖开始出现抑制（P<0.01）,并呈浓度和时间依赖性;10^-8 mol·L^-1 CGRP预处理后细胞增殖活性最高,与只加入10^-4 mol·L^-1 H₂O₂有统计学差异（P<0.01）。2）与H²O²组相比,CGRP+H₂O₂组SOD活性升高（P<0.01）,TNF-α、IL-1β、IL-6水平降低（P<0.05）,ROS含量降低（P<0.01）。结论 H₂O₂会对MC3T3-E1成骨细胞造成氧化损伤,CGRP对MC3T3-E1成骨细胞氧化损伤具有保护作用。     

不同体积分数氧气对山羊颞下颌关节盘细胞骨架改建的影响

目的 探讨不同体积分数的氧气对山羊颞下颌关节盘细胞3种细胞骨架蛋白改建的影响。方法 体外分离、培养山羊颞下颌关节盘细胞,传代至第2代,分别于常氧21%O₂及低氧8%O₂、4%O₂、2%O₂下培养。甲苯胺蓝、天狼星红及Ⅰ型胶原免疫细胞化学染色观察不同氧体积分数下细胞显型的变化。细胞免疫荧光染色和实时定量逆转录聚合酶链反应检测细胞骨架蛋白,包括肌动蛋白、微管蛋白和波形蛋白的表达情况。结果 不同氧体积分数下关节盘细胞仍然具有成纤维特性,3种细胞骨架蛋白有规律地排列。4%O₂时,肌动蛋白和波形蛋白荧光强度最低（P<0.05）;2%O₂时,微管蛋白荧光强度最高（P<0.05）,其他各组间差异无统计学意义（P>0.05）。检测肌动蛋白mRNA表达,21%O₂组最高,而2%O₂组和4%O₂组最低（P<0.05）;微管蛋白mRNA表达在2%O₂组最高,8%O₂组最低（P<0.05）;波形蛋白mRNA表达,在4%O₂组最低,21%O₂组最高,差异有统计学意义（P<0.05）。结论 在不同氧体积分数条件下,细胞骨架蛋白有不同程度的改建,2%O₂可能是适合颞下颌关节盘细胞扩增的最佳氧体积分数。     

SLM 3D打印钛网表面聚氨酯涂层的涂覆及表面性能的研究

目的 采用聚氨酯电泳涂装方法对激光选区熔融(Selective laser melting, SLM)3D 打印 Ti6Al4V 钛网进行表面处理,以获得表面相对平滑、无金属粉末、凸峰的钛网,并探究其表面性能。方法 实验分组为 A组：常规处理;B1 组：SiO₂喷砂;B2 组：Al₂O₃喷砂;C1 组：SiO₂喷砂 +酸处理;C2 组：Al₂O₃喷砂 +酸处理;D1 组：聚氨酯涂层40 V;D2 组：聚氨酯涂层60 V;D3 组：聚氨酯涂层80 V。对各组试件表面形貌进行观察,并对其粗糙度、接触角、涂层厚度等进行检测。结果 聚氨酯涂层组各方面表面性能显著优于其他表面处理组(P<0.001)。15～20 μm 厚度的聚氨酯涂层表面无金属粉末,暴露的凸峰相对最少。结论 经聚氨酯涂层的 SLM3D 打印钛网表面高度平滑、疏水,无金属粉末、喷砂引入的杂质存在,涂层无异氰酸酯单体存在,有望降低 SLM 3D打印钛网对附着龈的刺激,降低术后感染发生,提高了...     

氧化铝喷砂对牙科用氧化锆基底与饰面瓷结合强度的影响

目的 研究氧化铝（Al₂O₃）喷砂对牙科用氧化锆基底与饰面瓷结合强度的影响。方法 按照ISO 9693的要求,制作（25±1） mm×（3±0.1） mm×（0.5±0.05） mm的片状氧化锆试样21个,随机分为3组：A组进行110目Al₂O₃喷砂;B组进行80目Al₂O₃喷砂;对照组不做喷砂处理。测定所有基底瓷的表面粗糙度以及基底瓷与饰面瓷的结合强度,扫描电镜（SEM）观察结合界面微观形貌,能谱分析（EDS）检测界面元素分布。结果 A组、B组和对照组基底瓷表面粗糙度分别为（1.272±0.149）、（0.622±0.113）、（0.221±0.065） μm;瓷瓷结合强度分别为（28.21±1.52）、（27.71±1.27）、（24.87±3.84） MPa。统计结果显示：各组间表面粗糙度的差异具有统计学意义（P<0.05）;A组和对照组之间结合强度的差异具有统计学意义（P<0.05）,而B组与A组和对照组之间的差异均无统计学意义（P>0.05）。破坏模式以结合界面附着破坏为主。SEM观察结果显示瓷瓷结合界面结合紧密,EDS结果表明界面无明显元素渗透现象。结论 Al₂O₃喷砂能提高基底瓷与饰面瓷的结合强度,但其作用不明显。     

尼古丁调控人牙周膜细胞自噬水平的实验研究

目的 探讨尼古丁对人牙周膜细胞（hPDLCs）自噬水平的影响。方法 选取因正畸治疗而拔除的前磨牙,采用组织块法分离培养hPDLCs。通过Western blot法筛选尼古丁影响hPDLCs自噬的最佳作用时间及浓度,使用透射电子显微镜（TEM）和免疫荧光染色法检测该作用时间及浓度下hPDLCs自噬体形成情况和自噬标志蛋白LC3的表达情况。结果 LC3Ⅱ蛋白表达在尼古丁作用的12 h内持续升高,从而确定12 h为最佳作用时间;LC3Ⅱ蛋白表达上调具有尼古丁浓度依赖性,1×10^-5 mol·L^-1为尼古丁最佳作用浓度。TEM和免疫荧光染色证实尼古丁在此浓度及作用时间下hPDLCs细胞质内自噬体的数量增加,自噬标志蛋白LC3表达升高。结论 在一定条件下,尼古丁能够上调hPDLCs自噬水平,为进一步研究细胞自噬与吸烟相关牙周炎的关系奠定了基础。     

Nd:YAG激光表面处理对树脂粘接剂与氧化锆粘接强度影响的meta分析

目的:试用Meta分析研究Nd:YAG激光表面处理对树脂粘接剂与氧化锆粘接强度的影响,为提高树脂粘接剂与氧化锆的粘接强度提供循证证据。方法:通过计算机检索PubMed、Cochran Library、EMbase、CNKI、维普、万方等数据库,查找Nd:YAG激光表面处理氧化锆的相关研究,采用RevMan5.2软件对纳入的研究进行Meta分析。结果:共纳入8个研究,合计290个样本。Meta分析结果显示:Nd:YAG激光表面处理组与对照组比较,剪切粘接强度（P=0.02）和粗糙度（P=0.0001）均高于对照组,差异有统计学意义;Nd:YAG激光表面处理组的剪切粘接强度与Al₂O₃喷砂组比较,差异无统计学意义（P=0.87）,Nd:YAG激光表面处理组的粗糙度高于Al₂O₃喷砂组,差异有统计学意义（P=0.02）。结论:Nd:YAG激光表面处理能增加树脂粘接剂与氧化锆的粘接强度,但目前尚不能认为Nd:YAG激光表面处理优于Al₂O₃喷砂处理。     

口腔中过氧化氢的来源及在微生态平衡中的作用

过氧化氢（H₂O₂）作为口腔中一种重要的抑菌物质,在口腔微生态平衡中发挥着重要作用。在口腔龈上菌斑定植的先锋菌中,约有80%细菌属于口腔链球菌属,这些口腔链球菌可以利用不同的氧化酶合成H₂O₂,同时H₂O₂可通过抑制对H₂O₂敏感的微生物参与菌间竞争拮抗,使氧耐受菌得以存活,从而调节生物膜的发展过程;H₂O₂还可通过影响微生物细胞外DNA的释放和感受态细胞的形成进而影响基因的水平转移,调节生物膜对口腔环境的适应能力;同时口腔微生物也可通过一系列机制耐受H₂O₂。此外,H₂O₂在微生物与宿主的关系中也发挥着重要作用。本文就口腔中H₂O₂的来源及其在口腔微生态平衡的作用两方面的研究进展进行综述。     

不同频率铒激光对氧化锆陶瓷粘接性能的影响

目的: 评价不同频率铒钇铝石榴石（erbium-doped yttrium aluminum garnet,Er:YAG）激光对氧化锆陶瓷粘接性能的影响。方法: 制作3 mm×3 mm×2 mm的钇稳定四方多晶氧化锆（yttrium-stabilized tetragonal zirconia polycrystals,Y-TZP）试件,随机分为6组,即空白对照组（C组）、喷砂组（SB组）和Er:YAG激光蚀刻组（A1-A4组）,频率分别为5、10、15和20 Hz,IPS e.max Press压铸陶瓷为B组,记录各组扫描电镜图像。将陶瓷试件粘接到牙试件上,37 ℃恒温水浴,保存24 h后进行剪切实验,随后在体视显微镜下观察各个试件的断裂模式。采用SPSS 26.0软件包对实验数据进行统计学分析。结果: 扫描电镜显示,不同频率的Er:YAG激光照射Y-TZP陶瓷后,与C组相比,Y-TZP陶瓷表面变得粗糙。剪切实验结果显示,B组剪切强度值最高,为（13.15±2.97） MPa;其次为SB组[（7.78±0.97） MPa]和A2组[（7.13±0.75） MPa],SB组与A2组相比无统计学差异（P>0.05）。断裂模式结果显示,C组断裂模式以Y-TZP陶瓷与树脂粘接剂界面断裂为主,A1-A4组和SB组断裂模式大多为Y-TZP陶瓷与树脂粘接剂界面断裂,少部分为混合断裂和树脂粘接剂内聚断裂,B组断裂模式全部为混合断裂。结论: 10 Hz Er:YAG激光照射Y-TZP陶瓷可替代110 μm直径的Al₂O₃颗粒喷砂,用于Y-TZP陶瓷的表面改性,增加了Y-TZP陶瓷与树脂粘接剂的粘接强度。     

牙科纳米氧化铝陶瓷粉体的制备

目的:探讨牙科纳米氧化铝陶瓷粉体的制备工艺。方法:应用溶胶-凝胶法,比较不同前驱物浓度、pH 值、热处理温度及时间等条件下所制备氧化铝粉体的物理性能。结果:Al (NO3 ) 3 ·9H2O 溶液浓度为011 molPL、pH = 9时,经1200 ℃煅烧10 min 后,可获得性能优良、粒径约为70 nm的氧化铝陶瓷粉体。结论:选择适当的反应条件可制得粒径小、团聚少的纳米氧化铝陶瓷粉体。     

Mechanical properties of dental zirconia ceramics changed with sandblasting and heat treatment

Two types of tetragonal zirconia polycrystals (TZP), a ceria-stabilized TZP/Al2O3 nanocomposite (CZA) and a conventional yttria-stabilized TZP (Y-TZP), were sandblasted with 70-microm alumina and 125-microm SiC powders, then partially annealed at 500-1200 degrees C for five minutes. Monoclinic ZrO2 content was determined by X-ray diffractometry and Raman spectroscopy. Biaxial flexure test was conducted on the specimens before and after the treatments. Monoclinic ZrO2 content and biaxial flexure strength increased after sandblasting, but decreased after heat treatment. However, in both cases, the strength of CZA was higher than that of Y-TZP. Raman spectroscopy showed that a compressive stress field was introduced on the sample surface after sandblasting. It was concluded that sandblasting induced tetragonal-to-monoclinic phase transformation and that the volume expansion associated with such a phase transformation gave rise to an increase in compressive stress on the surface of CZA. With the occurrence of such a strengthening mechanism in the microstructure, it was concluded that CZA was more susceptible to stress-induced transformation than Y-TZP.     

Effect of various surface conditioning methods on the adhesion of dual-cure resin cement with MDP functional monomer to zirconia after thermal aging

This study evaluated the effect of chairside and laboratory types of surface conditioning methods on the adhesion of dual-cure resin cement with MDP functional monomer to zirconia ceramic after thermocycling. Disk-shaped (diameter: 10 mm, thickness: 2 mm) Y-TZP ceramics (Lava, 3M ESPE) were used (N=40) and finished with wet 1200-grit silicon carbide abrasive paper. Specimens were randomly divided into four experimental groups according to the following surface conditioning methods (n=10 per group): Group 1--Chairside airborne particle abrasion with 50-microm Al2O2 + Alloy Primer (Kuraray); Group 2--Airborne particle abrasion with 50-microm Al2O3 + Cesead II Opaque Primer (Kuraray); Group 3--Airborne particle abrasion with 50-microm A12O3 + Silano-Pen + silane coupling agent (Bredent); Group 4--Laboratory tribochemical silica coating (110-microm Al2O3 + 110-microm SiOx) (Rocatec) + silane coupling agent (ESPE-Sil). Adhesive cement, Panavia F 2.0 (Kuraray), was bonded incrementally to the ceramic surfaces using polyethylene molds (diameter: 3.6 mm, height: 5 mm). All specimens were thermocycled (5 and 55 degrees C, 6,000 cycles) and subjected to shear bond strength test (1 mm/min). Data were statistically analyzed (one-way ANOVA, alpha=0.05), whereby no significant differences were found among the four groups (8.43+/-1.3, 8.98+/-3.6, 12.02+/-6.7, and 8.23+/-3.8 MPa) (p=0.1357). Therefore, the performance of chairside conditioning methods used for zirconia was on par with the laboratory alternative tested.     

Y-TZP口腔修复材料的低温老化及抗低温老化的相关研究

综合国内外相关研究,了解氧化钇稳定的四方氧化锆多晶陶瓷(Y-TZP)口腔修复材料的低温老化现象,探讨抗Y-TZP修复陶瓷低温老化的方法,展望抗低温老化Y-TZP陶瓷在口腔临床中的应用.抗Y-TZP低温老化的方法包括:稳定剂类型和含量的选择、加工工艺的改善、适宜的表面处理、合成复合陶瓷等,其中Y-TZP/Al2O3复合陶瓷对Y-TZP的低温老化有较大程度的缓解作用,且能明显改善Y-TZP的机械性能,是一种在口腔临床应用中具有发展前景的氧化锆基陶瓷材料.     

Effects of preparation conditions in aqueous solution on properties of hydroxyapatites

Hydroxyapatite powders (HAP: Ca10(PO4)6(OH)2) were prepared from calcium nitrate and di-ammonium hydrogen phosphate at various temperatures in aqueous solution in the absence and presence of carbon dioxide. In the absence of carbon dioxide, the crystallinities as well as the calcium to phosphate ratio (Ca/P ratio) of HAP powders increased with an increase in the preparation temperature. Calcium ion deficiency caused low Ca/P ratios of HAP powders. Such HAP powders decomposed thermally to beta-tricalcium phosphate (beta-TCP: Ca3(PO4)2) at 800 degrees C in 3 hours whereas HAP powders with sufficient calcium were stable at 1200 degrees C for 3 hours. In the presence of carbon dioxide as well the crystallinities of HAP powders increased with an increase in the preparation temperature, but carbonate-bearing HAPs were obtained instead of pure HAP. In addition, calcium carbonate was obtained along with carbonate-bearing HAP prepared below 60 degrees C.     

氧化锂和氧化镧对牙科ZTA复合陶瓷渗透用玻璃粉性能的影响

目的:研究不同含量氧化镧(La2O3)及氧化锂(Li2O)对ZTA复合陶瓷渗透玻璃粉性能的影响,并优选出性能最佳的玻璃组分.方法:通过熔融淬冷方法制备6组(Li1 、Li2、Li3 、La1 、La2、La3)不同的玻璃粉,均匀涂布在经1200℃预烧结凝胶注模成型的ZTA陶瓷初坯上,经过1150℃玻璃渗透2次后,制得ZTA复合陶瓷对玻璃试样进行差热分析及熔融范围测定,并对预烧结体及玻璃渗透ZTA复合陶瓷弯曲强度、线性收缩率进行测试,扫描电镜及能谱分析复合材料断面微观结构及元素变化,应用SPSS13.0软件包对数据进行配对t检验和单因素方差分析,优选出性能最佳的渗透玻璃粉.结果:不同含量的La2O3和Li2O影响ZTA复合陶瓷渗透玻璃粉的性能.其中,Li1组复合陶瓷抗弯强度最高,可达(291.2±27.9)MPa,显著高于Li2组和La2组(P＜0.05),且线性收缩率仅为(1.85±0.27)％扫描电镜及能谱分析显示,该组断面结构较其他组致密,玻璃相充盈了陶瓷初坯的网络孔隙,玻璃与ZTA陶瓷界面过渡平滑,相互渗透,同时可见穿晶和沿晶断裂2种方式 结论:测试结果显示,Li1(30％La2O3-15％Al2O3-15％SiO2-15％B2O3-5％Li2O)组玻璃渗透ZTA复合陶瓷各项性能最佳.通过凝胶注模成型技术结合玻璃渗透制备ZTA复合陶瓷,能显著简化工艺,降低成本,为临床应用奠定了基础.     

Effect of alloy type and surface conditioning on roughness and bond strength of metal brackets.

The effect of 5 different surface conditioning methods on bonding of metal brackets to cast dental alloys was examined. The surface conditioning methods were fine (30-microm) or rough (125-microm) diamond bur, sandblasting (50-microm or 110-microm aluminum oxide [Al2O3]), and silica coating (30-microm silica). Fifty disc-shaped specimens of 5 different alloys (gold-silver, palladium-silver, nickel-chromium, cobalt-chromium, and titanium) were ground with 1200-grit silicone carbide abrasive and polished before being reused for each conditioning method. Polished surfaces were used as negative controls. After measuring surface roughness (RZ), metal brackets were bonded to the conditioned alloys with a self-curing resin composite. Specimens were thermocycled (5000 times, 5 degrees-55 degrees C, 30 seconds), and shear bond tests were performed. Significantly higher (P<.001) surface roughnesses were observed with use of the rough diamond bur (RZ approximately 33 microm), 110-microm Al2O3 (RZ approximately 14 microm), and fine diamond bur (RZ approximately 10 microm), compared with the controls (RZ approximately 1 microm). Silica coating (RZ approximately 4 microm) and 50-microm Al2O3 (RZ approximately 4 microm) demonstrated no significant difference (P>.001) in roughness when compared with the controls. The control group showed no resistance to shear forces (0 MPa). Bond values were greater (19 MPa) when silica coating was used, compared with 50-microm Al2O3 (7 MPa) and 110-microm Al2O3 (8 MPa) for all alloys tested. However, interaction between alloys and conditioning methods exhibited significant differences (P<.0001).     

The crystallization of an aluminosilicate glass in the K2O-Al2O3-SiO2 system.

OBJECTIVES: The aims of the study were to explore the nucleation and crystallization kinetics of an aluminosilicate glass in K2O-Al2O3-SiO2 system and to characterize it. OBJECTIVES: A starting glass composition of wt%; 64.2% SiO2, 16.1% Al2O3, 10.9% K2O, 4.3% Na2O, 1.7% CaO, 0.5% LiO and 0.4% TiO2 was heated in an electric furnace and later quenched to produce glasses. The glass powders were heat treated using differing heat treatment schedules and quenched. Dta, Xrd, Eds and Sem analyses were used to characterize and explore the crystallization kinetics of the glasses. RESULTS: Phase separation of the glasses was identified and characterized in the glasses. Tetragonal leucite, cubic leucite and sanadine glass-ceramics were produced. Fine leucite crystals (1 microm2) were crystallized with minimal matrix microcracking. SIGNIFICANCE: Amorphous phase separation appeared to be an important precursor to nucleation and crystal growth in the alkali aluminosilicate glasses explored. It was possible to control the crystallization of tetragonal leucite and sanidine phases by selected heat treatment of glass powders and monoliths, resulting in the production of fine grained tetragonal leucite glass-ceramics.     

Fatigue strength of Ce-TZP/Al2O3 nanocomposite with different surfaces

Ce-TZP/Al(2)O(3) nanocomposite (NANOZR) has not only higher strength, but also higher fracture toughness than conventional Y-TZP, indicating its potential for use in dental implants. Surface treatment to obtain osseointegration, however, may alter its surface topography, thus affecting the cyclic fatigue strength that plays such an important role in the durability of this material. The aim of this study was to evaluate the influence of surface treatment on cyclic fatigue strength in NANOZR as compared with grit-blasted and acid-etched Y-TZP (125BE Y-TZP). Bi-axial flexure strength was measured in both static and cyclic fatigue tests, as recommended by ISO 6872. The cyclic fatigue test was performed by the staircase method in distilled water at 37°C, with a load of 10(6) cycles and 10 Hz. Bi-axial flexure strength of NANOZR was 1111-1237 MPa and 667-881 MPa in the static and cyclic fatigue tests, respectively. The bi-axial flexure strength of NANOZR under all conditions was greater than that of 125BE Y-TZP in the static and cyclic fatigue tests. The cyclic fatigue strength of NANOZR was more than twice that of Y-TZP as specified in ISO 13356 for surgical implants (320 MPa), indicating the promise of this material for use in dental implants.     

不同表面处理方法对氧化锆陶瓷微观结构和粘接强度影响的研究

目的 研究不同机械-化学性表面处理对氧化锆陶瓷表面微观形貌、结构及组成的影响,比较不同表面改性后的氧化锆陶瓷与人牙本质的粘接强度。方法 选择氧化锆陶瓷（IPS e.max ZirCAD）,切割并烧结形成长6 mm、宽6 mm、高5 mm瓷块126块,随机分为7组,每组18块,分别进行如下处理。A组：不处理,对照组;B组：50 μm氧化铝喷砂;C组：50 μm氧化铝喷砂+30 μm二氧化硅蚀刻;D组：50 μm氧化铝喷砂+30%硅溶胶涂层;E组：110 μm氧化铝喷砂;F组：110 μm氧化铝喷砂+30 μm二氧化硅蚀刻;G组：110 μm氧化铝喷砂+30%硅溶胶涂层。每组随机抽取2个试件,分别用表面粗糙度轮廓仪测量表面粗糙度（R_a）,X射线衍射（XRD）观察表面晶相结构,能谱分析仪（EDX）分析表面化学元素组成,扫描电镜（SEM）观察表面微观形貌。收集70颗人离体第三磨牙制备成牙本质平面。使用双固化树脂水门汀将氧化锆试件与牙本质平面粘接,万能试验机进行剪切粘接强度（SBS）测试。采用SPSS 17.0软件对结果进行单因素方差分析及多重检验。结果 与对照组相比,表面处理后的氧化锆陶瓷R_a具有显著性差异（P<0.05）。所有表面处理后都发生了四方相（t）到单斜相（m）的晶相转换,且热处理后的m相体积分数最多。表面改性后化学元素组成发生变化,EDX结果显示硅涂层后,硅元素含量显著升高,Zr、Y、Hf减少。SEM图像显示,氧化铝喷砂后的氧化锆陶瓷表面出现一些微小断裂、晶界消失;硅溶胶薄膜烧结后体积明显收缩,可见裂纹与剥离。不同表面处理组的粘接强度有统计学差异（P<0.05）,F和G组SBS值最大,其次为C和D组,显著大于B和E组（P<0.05）,对照组的SBS值最小（P<0.05）。结论 氧化铝喷砂、硅粉蚀刻、硅溶胶涂层法可显著改变氧化锆陶瓷的表面形貌、结构和组成,有利于氧化锆陶瓷与牙体组织粘接时形成微机械嵌合与化学结合作用。氧化铝喷砂后硅涂层处理是一种比较理想的表面改性方法,可显著提高氧化锆陶瓷与牙体组织的粘接强度。