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1.
氧化锆陶瓷兼具优异的力学性能和美学性能,在口腔医学领域应用广泛。然而,临床常用的四方相氧化锆陶瓷在口腔环境中可发生低温老化,导致修复体表面粗糙度增加、微裂纹产生、力学性能下降等。氧化锆陶瓷低温老化受晶体大小、应力、稳定剂含量和类型、表面处理、烧结条件等因素影响,本文就口腔修复学领域氧化锆陶瓷低温老化的研究进展进行综述,...  相似文献   

2.
目的:初步分析一种3摩尔钇稳定的纳米氧化锆陶瓷(Tz—Px一242A)的低温老化性能。方法:将烧结后的氧化锆试件随机分成4组,在高温高压灭菌锅里进行循环热处理,处理条件为在134℃、0.2MPa下,进行0h,1h,3h,5h不同时间的低温老化实验。测量低温老化实验前后的三点弯曲强度,并用XRD分析试件表面单斜相的比例。结果:随着低温老化时间的延长,试件表面单斜相含量增加,三点弯曲强度呈逐渐下降趋势。低温老化处理5h后强度仍高于1100MPa。结论:本实验用氧化锆陶瓷的低温老化性能具有时效依赖性,低温老化对三点弯曲强度无明显影响。:  相似文献   

3.
氧化锆全瓷材料具有良好的美学性能、生物相容性和力学性能,已被广泛应用于口腔医学领域。其中Y-TZP目前在临床应用上最为广泛,但在生物体内或口腔环境条件下存在低温老化现象。Ce-TZP/Al2O3复相陶瓷材料具有良好的抗低温老化特性及优良的综合力学性能,目前受到学者的极大关注。本文对Ce-TZP/Al2O3复相陶瓷在口腔医学领域的研究现状进行综述,旨在为Ce-TZP/Al2O3复相陶瓷的临床应用与相关研究提供一定的指导作用。  相似文献   

4.
氧化锆陶瓷材料因具有与天然牙较接近的物理性质、透光性和较好的生物相容性、美观效果,较快地成为了目前口腔修复中的热点.自2001相继出现髋关节置换体失败案例与氧化锆低温老化现象有关后,低温老化变成为口腔材料应用领域的研究热点.大量研究表明氧化锆老化现象与稳定剂的种类、含量,残余应力以及晶粒尺寸相关,本文梳理和总结关于牙科氧化锆老化相关文献,从老化性能和影响因素方面进行深入探讨.  相似文献   

5.
目的 评估快速烧结和低温老化对高透氧化锆半透性的影响。方法 利用常规烧结和快速烧结分别烧结高强氧化锆ST和高透氧化锆TT,分别进行0、5和20 h的低温老化处理后,采用Shade Eye NCC电脑比色仪在标准黑白背景下测量色彩学特征参数(L*、a*、b*值),使用半透明参数(TP)评估材料半透明性。结果 快速烧结会降低ST的TP值,会升高TT的TP值。低温老化对TT的TP值没有影响;常规烧结的ST的TP值随着老化时间的延长降低,快速烧结组没有显著变化。结论 快速烧结会降低高强氧化锆的半透性,改善高透氧化锆的半透性。低温老化对高透氧化锆的半透性没有影响。就半透性而言,建议用快速烧结的方式烧结高透氧化锆。  相似文献   

6.
牙科用氧化锆陶瓷由于其良好的力学性能、高温稳定性、生物安全性和低热传导率,现已广泛应用于临床,特别是后牙全冠及固定桥修复。然而,在相对较低的温度及潮湿的环境下,氧化锆发生由部分稳定的四方晶相向单斜晶向的改变,即低温时效现象,影响其力学性能。本文探讨了牙科用氧化锆的低温时效及其影响因素,并讨论了改善其抗低温时效性的途径。  相似文献   

7.
目的评价两种典型食用酸(醋酸、柠檬酸)在常温下对牙科氧化钇稳定四方相氧化锆陶瓷(Y-TZP)机械性能和微观结构的影响,探讨食用酸对临床上Y-TZP修复体使用安全性的影响。方法制作30枚条状氧化锆陶瓷试样,随机分为6组,并进行以下处理:阴性对照组(A组)试样不处理;阳性对照组(B组)试样放入高压灭菌器,在134℃、0.2 MPa条件下加速老化20 h;酸溶液浸泡组试样分别于10%醋酸或20%柠檬酸溶液中浸泡7 d(C组、E组)或14 d(D组、F组)。测试表面维氏硬度,计算断裂韧性。各组典型试样以扫描电镜观察表面微观结构。结果醋酸和柠檬酸浸泡并未改变Y-TZP试样的表面维氏硬度。D组断裂韧性显著降低。电镜下未发现6组试样表面微观结构的改变。结论常温下柠檬酸不会影响Y-TZP修复体的机械性能和微观结构;长期接触醋酸会造成Y-TZP断裂韧性的显著降低,影响Y-TZP修复体的临床使用寿命。  相似文献   

8.
[摘要] 目的 研究打磨、抛光、上釉及老化对氧化锆陶瓷抗折强度的影响。方法 将36片氧化锆陶瓷分成打磨组、抛光组、上釉组3组,每组试件按不同的老化时间分为0 h组(对照组)和10 h组(n=6)。将10 h组瓷块置于134 ℃,0.2 MPa 的水热环境下,进行10 h的老化试验。每组各取一个试件,用 X 线衍射 ( X-ray diffraction,XRD ) 仪测定单斜相含量,万能力学试验机测试所有试件抗折强度。结果 XRD分析显示老化前的所有试件均未显示单斜相。老化后所有组均出现单斜相,打磨组单斜相含量最高,上釉组最低。抗折强度所有组均无统计学意义(P>0.05)。结论 老化后所有试件单斜相含量均有所增加,但打磨、抛光、上釉及老化处理对氧化锆陶瓷抗折强度未产生影响。  相似文献   

9.
目的 研究纳米氢氧化锆在氧化锆陶瓷表面形成碱性涂层后对10-甲基丙烯酰氧癸二氢磷酸酯(MDP)与氧化锆陶瓷粘接强度的影响。方法 制作氧化钇稳定四方相氧化锆(Y-TZP)瓷片140枚,氧化铝喷砂后对其表面进行不同的处理,制作粘接试件并测试剪切粘接强度。以X线光电子能谱(XPS)检测Y-TZP陶瓷表面依次经过纳米氢氧化锆涂层和含有MDP的底涂剂处理后的化学键变化。结果 老化前,与对照组相比,两种碱性涂层均能提高短期粘接强度值,纳米氢氧化锆涂层增强效果更显著。老化后,各组粘接强度值差异无统计学意义,但较老化前均显著降低(P<0.05)。XPS在制备纳米氢氧化锆涂层的Y-TZP瓷片表面检测到-OH键,在制备纳米氢氧化锆涂层的Y-TZP陶瓷应用含有MDP的底涂剂处理后检测出-P-O-Zr键。结论 在氧化锆陶瓷表面制备碱性涂层能够使MDP提高氧化锆陶瓷粘接强度。  相似文献   

10.
《口腔医学》2014,(8):592-596
目的评价氧化锆陶瓷经几种表面处理后在不同强度的人工老化实验条件下的粘结耐久性。方法制备4组氧化锆陶瓷/树脂粘结试件128个,各组试件氧化锆陶瓷按照以下方式处理并使用不同种类的树脂水门汀。组A,摩擦化学法硅涂层+硅烷偶联剂;组B,氧化铝喷砂;组C,氧化铝喷砂+应用氧化锆涂底剂Z-Prime Plus;组D,氧化铝喷砂+应用氧化锆涂底剂Z-Prime Plus。组A和C使用传统Bis-GMA基光固化树脂水门汀,组B和D使用自粘结树脂水门汀。各实验组再分为4个亚组接受不同的人工老化。不接受人工老化(a),水储40 d(b);冷热循环1 200次(c);水储40 d后冷热循环12 000次(d)。测试各组剪切粘结强度值并进行统计学分析。摩擦化学法硅涂层和氧化铝喷砂的氧化锆陶瓷表面以扫描电镜观察并进行能谱分析。结果不论接受或不接受人工老化,4种表面处理间对氧化锆陶瓷的粘结强度值影响无统计学差异。各实验组单独来看,仅有人工老化方式d时粘结强度值都出现了下降,差别具有统计学意义。结论不同人工老化强度对氧化锆陶瓷粘结强度的影响不同。  相似文献   

11.
目的口腔全瓷修复体以其独特优越性受到医患青睐,但脆性问题一直限制其应用范围及使用可靠性.本研究旨在研制用于玻璃渗透全瓷修复的纳米氧化锆增韧陶瓷并全面检测评价其力学性能.方法采用化学共沉淀与球磨相结合的方法合成纳米氧化锆增韧陶瓷(α-Al2O3/nZrO2 ceramics powder ,W),扫描电镜评价陶瓷材料的粉体形态特征及粒度分布.预制氧化锆含量不同的陶瓷粉体(5wt%,10wt%,15wt% and 20wt%),采用粉浆涂塑技术将材料制成标准试件,并在不同温度下(1 200~1 600 ℃)烧结成型,用三点弯曲法及单边刀口梁法检测材料试件的抗弯强度和断裂韧性.结果1)α-Al2O3/nZrO2材料粉体粒度分布范围大致为0.02~3.0 μm,其中超细粉体(低于0.1 μm)占20%; 2)不同烧结温度组试件的力学强度有显著差异(P<0.05),1 450 ℃和1 600 ℃组高于1 200 ℃组;3)相同烧结温度下不同氧化锆含量组材料强度有显著差异,一定范围内氧化锆含量增高有助于材料的增韧增强.结论本研究所研制的纳米氧化锆增韧陶瓷材料组分配比及微观特征能增韧增强材料,有望提高玻璃渗透后材料的综合力学性能.  相似文献   

12.
ObjectiveTo test the impact of three varying step-stress protocols on the fatigue behavior of two 3Y-TZP, one 4Y-TZP and one 5Y-TZP zirconia materials.MethodsEight specimens per zirconia material (N = 32) were selected for static testing to determine the start load for dynamic tests (30% of the mean value of static fracture load). 45 specimens per material (N = 180) were used for dynamic load tests using three step-stress protocols: 1. 50 N/5000 cycles; 2. 5% of static load/5000 cycles, and 3. 10 N/1000 cycles. Following materials were tested: 3Y-TZP(<0.25 Al2O3) (O: opaque) 3Y-TZP(<0.05 Al2O3) (T: translucent), 4Y-TZP(<0.01 Al2O3) (ET: extra translucent) and 5Y-TZP(<0.01 Al2O3) (HT: high translucent). The specimens (4 ± 0.02 × 3 ± 0.02 × 45 mm) were placed centrally on the support rolls and the load was applied perpendicularly over the 4 mm specimen side (~4-point flexural strength according to the DIN 6872:2019). Data was analyzed with Kolmogorov–Smirnov-test, t-test, one-way ANOVA with post-hoc Scheffé-test, Chi-square-test, Kaplan–Meier with Log-Rank-test and two-parametric Weibull analysis (p < 0.05).ResultsThe step-stress protocols showed no impact on the fracture load or Weibull modulus within one zirconia material. However, the zirconia materials T, ET and HT showed differences in cycle number to fracture between the step-stress protocols (T: 3 > 2 > 1; ET: 2 > 3 > 1; HT: 2, 3 > 1) with lowest cycle number to fracture for protocol 1. Within one step-stress protocol, the cycle number to fracture varied according to the zirconia material as follows: 1: T, O ≥ O, ET > HT; 2: ET > O, T, HT; 3: O, T, ET > HT. Cracking started at the tensile side of the specimens at all times. All specimens showed typical compression curls (single or double). Fragmentation patterns were similar for all materials with a lot of crack branching and fragmentation due to secondary cracks indicating high energy fractures.SignificanceDynamic fatigue tests seem to provide important information on the long-term stability of zirconia materials. Zirconia materials with higher opacity seem to be more robust towards varying step-stress protocols than translucent zirconia materials. Regarding expenditure of time, a step-stress protocol with a load increase of 50 N every 5000 cycles seems favorable to gain information on the long-term stability of zirconia materials.  相似文献   

13.
The purpose of this study was to use a tape casting technique to develop an Al2O3 fiber-reinforced Al2O3-based ceramic material (Al2O3-fiber/Al2O3 composite) into a new type of dental ceramic. The Al2O3-based ceramic used a matrix consisting of 60 wt% Al2O3 powder and 40 wt% SiO2-B2O3 powder. The prepreg sheets of Al2O3-fiber/Al2O3 composite (in which uniaxially aligned Al2O3 fibers were infiltrated with the Al2O3-based matrix) were fabricated continuously using tape casting technique with a doctor blade system. Multilayer preforms of Al2O3-fiber/Al2O3 composite sheets were then sintered at a maximum temperature of 1000 degrees C under an atmospheric pressure in a furnace. The results showed that the shrinkage and bending properties of Al2O3-fiber/Al2O3 composite exceeded those of unreinforced Al2O3--hence demonstrating the positive effects of fiber reinforcement. In conclusion, the tape casting technique has been utilized to successfully develop a new type of dental ceramic material.  相似文献   

14.

STATEMENT OF PROBLEM

Recently Yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) has been introduced due to superior flexural strength and fracture toughness compared to other dental ceramic systems. Although zirconia has outstanding mechanical properties, the phenomenon of decrease in the life-time of zirconia resulted from degradation in flexural strength after low temperature aging has been reported.

PURPOSE

The objective of this study was to investigate degradation of flexural strength of Y-TZP ceramics after various low temperature aging treatments and to evaluate the phase stability and micro-structural change after aging by using X-ray diffraction analysis and a scanning electron microscope (SEM).

MATERIAL AND METHODS

Y-TZP blocks of Vita In-Ceram YZ (Vita Zahnfabrik, Bad Säckingen, Germany) were prepared in 40 mm (length) × 4 mm (width) × 3 mm (height) samples. Specimens were artificially aged in distilled water by heat-treatment at a temperature of 75, 100, 125, 150, 175, 200, and 225℃ for 10 hours, in order to induce the phase transformation at the surface. To measure the mechanical property, the specimens were subjected to a four-point bending test using a universal testing machine (Instron model 3365; Instron, Canton, Mass, USA). In addition, X-ray diffraction analysis (DMAX 2500; Rigaku, Tokyo, Japan) and SEM (Hitachi s4700; Jeol Ltd, Tokyo, Japan) were performed to estimate the phase transformation. The statistical analysis was done using SAS 9.1.3 (SAS institute, USA). The flexural strength data of the experimental groups were analyzed by one-way analysis of variance and to detect statistically significant differences (α= .05).

RESULTS

The mean flexural strength of sintered Vita In-Ceram YZ without autoclaving was 798 MPa. When applied aging temperature at below 125℃ for 10 hours, the flexural strength of Vita In-Ceram YZ increased up to 1,161 MPa. However, at above 150℃, the flexural strength started to decrease. Although low temperature aging caused the tetragonal-to-monoclinic phase transformation related to temperature, the minimum flexural strength was above 700 MPa.

CONCLUSION

The monoclinic phase started to appear after aging treatment above 100℃. With the higher aging temperature, the fraction of monoclinic phase increased. The ratio of monoclinic/tetragonal + monoclinic phase reached a plateau value, circa 75% above 175℃. The point of monoclinic concentration at which the flexural strength begins to decrease was between 12% and 54%.  相似文献   

15.

Objectives

In this brief and selective overview, basic factors contributing to aqueous induced dissolution, phase changes of zirconia and mechanical strength degradation of dental ceramics are considered.

Methods

Dissolution is important for porcelain and glass-ceramic materials as they predominantly contain a silica glass structure with various other cations incorporated which disrupt the silica network. In glass-ceramic materials and porcelains containing crystalline components the situation is more complex as the difference in the dissolution rate may increase the surface roughness and contribute to abrasion of the opposing definition.

Results

Factors contributing to the aqueous dissolution of silicate based dental ceramics and induced destabilization of Y-TZP zirconia or low temperature degradation (LTD) are considered. It is also noted that there have been a number of reports of spontaneous fracture of 3Y-TZP specimens because of LTD in the absence of external stress. A simple analysis of this situation is presented which indicates a strong specimen-size effect and also implicates the role of the remnant “pseudo-grain” structure resulting from the pressing of spray-dried powder agglomerates.

Significance

The final section of this review addresses the consequences of various environments on crack growth and strength degradation. In some situations it is suggested that the aqueous environment may enhance the strength of restorative materials. In all instances discussed above the clinical consequences are pointed out.  相似文献   

16.
《Dental materials》2020,36(11):1418-1429
ObjectiveThe aims of this study were: 1) to evaluate the effect of sintering temperature on microstructure, density and flexural strength of a 3Y-TZP/TiO2 composite containing 12.5 wt% of TiO2 compared to 3Y-TZP specimens (control); 2) to compare 3Y-TZP with the experimental 3Y-TZP/TiO2 composite, both sintered at 1400 °C, with respect to the following parameters: optical properties, characteristic strength, Weibull modulus, fatigue behavior, induction of osteoblasts proliferation and differentiation (mineralization nodules formation).MethodsThe 3Y-TZP and 3Y-TZP/TiO2 powders were uniaxially pressed and sintered at 1200 °C, 1300 °C, 1400 °C or 1500 °C for one hour in a furnace. The microstructural analysis consisted of X-ray diffraction and scanning electron microscopy. The density was measured by the Archimedes' principle and the flexural strength was obtained by the biaxial flexure test. The optical properties were measured using a spectrophotometer operating in the visible light wavelength range. The step-stress accelerated life testing was performed by the pneumatic mechanical cycler and the biological behavior achieved by using osteoblast-like cells (Osteo-1 cell line).ResultsTetragonal zirconia was identified in all groups and cubic zirconia was identified only at 3Y-TZP group. The addition of TiO2 decreased the values of density and flexural strength of the composite 3Y-TZP/TiO2 in relation to 3Y-TZP regardless of the sintering temperature. The color difference between the two materials was not significant regarding L*a*b* parameters. The composite showed higher probability of failure, and induced higher proliferation and differentiation than control.SignificanceThe composite developed have good aesthetic and biologics properties. However, its microstructure and mechanical properties need to be improved for future dental implant applications.  相似文献   

17.
目的 研究时效对5种牙科氧化锆陶瓷结构稳定性的影响.方法 5种氧化锆预烧结块(A组:TZ-3YS;B组:Vita In-Ceram YZ;C组:Ivoclar;D组:Cercon Smart;E组:Kavo)各切取15 mm×15 mm×1.5 mm氧化锆试件18片,常压致密烧结.时效处理如下:置于高温高压消毒炉中进行循环热处理,条件是134℃,0.2 MPa压力,维持时间为0h、1h、2h、3h、4 h、5h.X射线衍射分析(X-ray diffraction,XRD)试件的晶相结构,计算试件表面单斜相(m相)的相对含量.原子力显微镜观察A组和D组时效1、4 h的抛光试件.A组氧化锆再制备25 mm×4 mm×1.2 mm的试件30根,均分为未退火组(时效前)、退火组(时效前)和时效组(时效后),测试试件的三点弯曲强度.结果 除D组试件外,A、B、C、E组试件的m相含量均随时效时间的延长而增加,A组试件的m相含量最高,E组次之,B组和C组相近.XRD未检测到D组试件表面有m相,但使用原子力显微镜可观察到D组试件有m相晶核的成核和生长.时效前后A组试件的三点弯曲强度未衰减,未退火组试件三点弯曲强度[(1301±169)MPa]显著高于退火组[(1120±185)MPa]和时效组[(1158±111)MPa],差异有统计学意义(P<0.05);而退火组与时效组间差异无统计学意义(P>0.05).结论 牙科氧化锆陶瓷的低温时效效应具有时间依赖性,但时效效应并未使TZ-3YS的三点弯曲强度降低.  相似文献   

18.
目的 研究非均相沉淀法制备3%氧化钇稳定的四方氧化锆多晶陶瓷(3Y-TZP)/3%Al2O3复合粉的最佳pH值;3Y-TZP/3%Al2O3/10%BN双相包覆中,合成Al2O3及非晶氮化硼(BN)的最佳热处理温度。方法 不同pH值(6.5、7.5、8.5、9.5)下,通过非均相沉淀法合成Al2O3前驱体包覆3Y-TZP粉,通过透射电镜(TEM)选出包覆形貌较均匀的一组。将此pH下制备的复合粉经不同的温度(800、1 000、1 200、1 400 ℃)处理后,硼酸尿素反应烧结法(N2保护下,850 ℃煅烧5 h,850 ℃煅烧3 h及800 ℃煅烧5 h,800 ℃煅烧3 h)合成10%BN包覆3Y-TZP/3%Al2O3粉,通过TEM、能谱分析及X射线衍射(XRD)选出形貌及相组成最佳的一组。结果 当pH值为8.5时,3%Al2O3前驱体均匀地包覆在3Y-TZP颗粒周围;3%Al2O3前驱体经1 200 ℃煅烧,再包覆10%BN,在N2保护下800 ℃煅烧5 h,此时可见3Y-TZP颗粒周围包覆Al2O3及非晶BN,3Y-TZP/3%Al2O3/10%BN复合粉中Al-B-O化合物较少,且t-ZrO2所占的比例最多。结论 合成Al2O3前驱体包覆3Y-TZP的最佳pH值为8.5;双相包覆中,Al2O3前驱体的最佳处理温度为1 200 ℃,合成非晶BN的适宜条件为N2保护下800 ℃煅烧5 h。  相似文献   

19.
氧化锆增韧纳米复合陶瓷粉体粒度与基体强度的关系   总被引:9,自引:0,他引:9  
目的 探讨氧化锆 (ZrO2 )粉体微观粒度、级配与材料增韧补强效果之间的关系。方法以采用包裹共沉淀法与湿法球磨方法合成的Al2 O3 nZrO2 纳米复合陶瓷粉体为研究对象 ,改变所添加ZrO2 粉体的粒度 ,对粉体形貌进行扫描电镜观察与粉体粒径的测定分析 ;以注浆法将粉体制成样本生坯 ,经 1 4 50℃烧结后 ,测定样本的抗弯强度与断裂韧性。结果 ①添加等量、不同粒度ZrO2 的Al2 O3 nZrO2 纳米复合渗透陶瓷材料 ,其基体抗弯强度与断裂韧性差异有显著性 (P <0 0 5) ;②添加粒度分布范围在 0 0 2~ 3 5μm ,包含粒径小于 0 5μm超细颗粒的ZrO2 组 ,增韧增强效果最显著 ,抗弯强度与断裂韧性分别达 (1 1 5 434± 5 31 9)MPa和 (2 0 4± 0 1 0 )MPam1 /2 。结论 添加ZrO2 的粉体粒度与级配是影响Al2 O3 nZrO2 纳米复合渗透陶瓷材料基体强度的重要因素  相似文献   

20.
During the past decade, zirconia-based ceramics have been successfully introduced into the clinic to fabricate fixed dental prostheses (FDPs), along with a dental computer-aided/computer-aided manufacturing (CAD/CAM) system. In this article (1) development of dental ceramics, (2) the current status of dental CAD/CAM systems, (3) CAD/CAM and zirconia restoration, (4) bond between zirconia and veneering ceramics, (5) bond of zirconia with resin-based luting agents, (6) surface finish of zirconia restoration and antagonist enamel wear, and (7) clinical evaluation of zirconia restoration are reviewed.Yttria partially stabilized tetragonal zirconia polycrystalline (Y-TZP) showed better mechanical properties and superior resistance to fracture than other conventional dental ceramics. Furthermore, ceria-stabilized tetragonal zirconia polycrystalline and alumina nanocomposites (Ce-TZP/A) had the highest fracture toughness and had resistance to low-temperature aging degradation. Both zirconia-based ceramics have been clinically available as an alternative to the metal framework for fixed dental prostheses (FDPs). Marginal adaptation of zirconia-based FDPs is acceptable for clinical application. The most frequent clinical complication with zirconia-based FDPs was chipping of the veneering porcelain that was affected by many factors. The mechanism for the bonding between zirconia and veneering ceramics remains unknown. There was no clear evidence of chemical bonding and the bond strength between zirconia and porcelain was lower than that between metal and porcelain.There were two alternatives proposed that might avoid chipping of veneering porcelains. One was hybrid-structured FDPs comprising CAD/CAM-fabricated porcelain parts adhering to a CAD/CAM fabricated zirconia framework. Another option was full-contour zirconia FDPs using high translucent zirconia. Combined application of silica coating and/or silane coupler, and 10-methacryloyloxydecyl dihydrogen phosphate is currently one of the most reliable bonding systems for zirconia. Adhesive treatments could be applied to luting the restorations and fabricating hybrid-structured FDPs. Full-contour zirconia FDPs caused concern about the wear of antagonist enamel, because the hardness of Y-TZP was over double that of porcelain. However, this review demonstrates that highly polished zirconia yielded lower antagonist wear compared with porcelains. Polishing of zirconia is possible, but glazing is not recommended for the surface finish of zirconia.Clinical data since 2010 are included in this review. The zirconia frameworks rarely got damaged in many cases and complications often occurred in the veneering ceramic materials. Further clinical studies with larger sample sizes and longer follow-up periods are required to investigate the possible influencing factors of technical failures.  相似文献   

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