【作者】 孙翔；

【导师】 陈吉华；

【作者基本信息】 第四军医大学 ， 口腔临床医学， 2008， 博士

【摘要】 云母玻璃陶瓷由于具有优良的可切削性能和与牙齿相近的半透明性成为一种较好的牙科CAD/CAM全瓷修复材料。传统的云母陶瓷产品无整体内着色瓷块,限制了其在修复领域的应用。本研究以一种实验用新型氟金云母玻璃陶瓷为基础,采用熔融法一次着色工艺,研究了不同热处理制度下不同种类、浓度着色氧化物添加对云母玻璃陶瓷颜色、透光性和性能的影响,在此基础上,初步制备出了临床可用的着色云母玻璃陶瓷;采用烧结法二次着色工艺制备了单色梯度云母玻璃陶瓷,研究了添加不同色料浓度对色度值和反射光谱的影响。具体研究结果如下:1.采用色差仪,测定了IPS e.max ceram全瓷系统基本瓷块的色度值和半透性。结果发现:该系统基本瓷块的色度学范围为L:68.48～93.26,a:-0.09～2.80,b:-3.26～13.49。相对透光率CR介于0.643～0.927之间。2.采用熔融法一次着色工艺,选用不同质量百分比的3种氧化物作为着色剂,制备了单色梯度云母玻璃陶瓷,并测量了其色度值。结果发现:添加CeO₂使玻璃陶瓷呈黄色,颜色随剂量增加而加深,向暗-黄色品方向发展。主要表现为b值升高,L值下降。添加Er₂O₃使玻璃颜色陶瓷呈粉红色,颜色随剂量增加而加深,向红色色品方向发展。主要表现为a值升高。添加Fe₂O₃使玻璃陶瓷呈现黄色至褐色,颜色随剂量增加改变,向暗红色品方向发展。主要表现为L值降低明显,a值增加,b值先增大后减小。3.选用9种热处理制度,对着色云母玻璃进行了热处理,评价了不同热处理制度对云母玻璃陶瓷着色效果的影响,运用SEM和XRD观察了着色试样微观结构。结果发现:不同热处理制度下着色云母玻璃陶瓷的颜色和半透性不同。具体表现为:随着热处理温度的提高和保温时间的延长,云母玻璃陶瓷的着色能力不同,透明性逐渐降低。SEM和XRD提示这与云母玻璃陶瓷不同热处理制度后的微观结构有关。获得云母玻璃陶瓷最佳着色效果和半透性的热处理温度为660℃左右,保温时间为1h。4.通过添加不同质量百分比的CeO₂,运用DTA、XRD、SEM、3点弯曲强度测试、显微硬度测试和切削性能测试,研究了添加着色氧化物对云母玻璃陶瓷结构和性能的影响。结果发现:添加2%～5%CeO₂不改变氟金云母玻璃陶瓷主晶相,但会改变云母玻璃陶瓷的微观结构。随着添加量的增加,晶体变长,变大。云母玻璃陶瓷的抗弯曲强度先增加后减小,可切削性能增加;向云母微晶玻璃中添加3%以下的CeO₂对力学性能有提高作用,而过高的添加比例虽提高了切削性能但造成了强度的下降。5.选用不同浓度的3种着色氧化物和不同的热处理制度,制备出了9种着色云母玻璃陶瓷试样,得到了颜色与Vita比色板A色系较为接近的云母玻璃陶瓷。其半透性良好,CR值为0.767,与IPS e.max ceram低透明度系列瓷块接近。6.采用烧结法制备了云母玻璃陶瓷,以烧结体收缩率为指标,SEM为手段,研究了不同烧结温度对云母玻璃陶瓷性能的影响。结果发现:在650～850℃范围内,随着烧结温度的升高,烧结体致密度增加,晶体数量增加,体积增大;对于本实验的云母玻璃陶瓷系统,采用以下烧结工艺:升温速度10℃/min,升温至850℃保温20min,然后降温至600℃保温1h,可以成功制备云母玻璃陶瓷。7.采用烧结法二次着色工艺制备了含不同质量百分比的锆铁红、锆铈镨黄和镍黑色料单色梯度玻璃陶瓷试样;研究了不同色料浓度对色度值和反射光谱的影响。结果显示:锆铁红色料主要影响试样的a值,锆铈镨黄色料主要影响b值,而镍黑色料则主要影响明度L值;随着锆铁红、锆铈镨黄和镍黑色料浓度的增加,烧结体的光谱反射率曲线在特定的光谱吸收波长区内呈现良好的递减趋势,不同浓度的曲线形态基本一致;随着色料浓度的等幅增加,3种色料烧结体的全波长K/S曲线也基本呈现等幅增长趋势;3种色料烧结体的K/S值与添加浓度的基本满足线性关系。3种色料的着色规律基本符合计算机配色数据库的要求。更多还原

【Abstract】 With excellent machinability, good translucency and proper strength, mica glass-ceramic has become one of ideal dental ceramic materials that can be fabricated with CAD/CAM. However, the lack of intrinsical coloration restricted its widespread application in dental clinic. In this study, the inner-colorized mica glass ceramic blocks were fabricated by appending the pigments to a novel mica-glass-ceramic based on SiO₂-Al₂O₃-Mg-Na₂O-K₂O-F mica glass-ceramic system for dental application by two ways. One is melting and casting technology, another is sintering technology. The results are as follow:1.The objective of this study was to observe color parameters of IPS e.max all-ceramic systems and give reference for coloration of one kind of mica glass-ceramic. The results showed the chroma values of IPS e.max blocks were L: 68.48⁹3.26, a:-0.09².80, b:-3.26¹3.49. The relative translucency of the blocks were between 0.643⁰.927.2.The objective of this study was to evaluate the coloration effects of three kinds of pigments with different concentrations on the mica glass-ceramic by melting and casting technique. Different concentrations of three kinds of pigments were added into samples, the chroma values were measured with chroma meter. The colors achieved by the different pigments were presented in the CIELab system. When adding CeO₂, the samples turned yellow and the b value increased, but L value decreased as the amount of CeO₂ increased.When adding Er_<sub>2O₃, the samples turned pink and the a﹡value increased as the amount of Er_<sub>2O₃. When adding Fe_<sub>2O₃, the samples turned from yellow to brown, and a﹡ value increased, L value decreased as the amount of Fe_<sub>2O₃ increased, while the b value firstly increased and then decreased.3.The objective of this study was to investigate the effects of different heat treatment process on the coloration of mica glass-ceramic. Nine kinds of heat treatment process including different temperature and holding times were chosen to treat the glass containing 1% CeO₂. The chroma value and relative translucency of samples were measured with chroma meter. The microstructure of samples were observed with SEM and analyzed with XRD. The results showed the mica glass-ceramic turned different shade and translucency with different heat treatment process for same kind of sample. The SEM and XRD results suggested these differences are related with the different structure. The preferred heat treatment process was treated at 660℃for 1h.4.To evaluate the effects of CeO₂ on the microstructure and property of SiO₂-Al_<sub>2O₃-Mg-Na₂O-K₂O-F system, 2-5%CeO₂ was added to base glass system respectively. DTA, XRD and SEM were used to observe the crystallization behavior, crystalline phases and microstructures of the samples. Three point bend strength, micro hardness and machinability were also measured. When adding CeO₂ to the glass-ceramics, the main crystalline phases were not changed, but the crystal became larger. With increasing of the CeO₂ concentration, three point bending strength firstly increased and then decreased, machinability increased and micro hard ness firstly decreased and then increased. The results suggested that the addition of CeO₂ changed the crystalline structure, increased the grain size of mica and machinability of mica glass-ceramics. Appropriate addition of CeO₂ does not change the strength of glass-ceramics. 5.To match the some special color porcelain corresponding to Vita shade, different concentrations of three kinds of pigments were added to the basic glass, and then the samples were treated with different heat-treatment process. Chroma value and translucency analysis were performed. Sample with special color were produced. The color difference analysis showed that the color of the materials obtained in this study was similar to that of Vita A1 and A2 shade.6.To fabricate the mica glass-ceramic by sintering technology, the effects of different sintering temperatures on crystalline structures and shrinkage rate were investigated. The relationship between shrinkage rate and sintering temperature showed that the increase of sintering temperature from 600℃to 850℃leads to the increase of the shrinkage rate. The XRD showed the crystalline phase was fluophlogopite mica when treated at 850℃.Improving crystallization temperature increased the rate of crystal and aspect ratio of the mica. The glass sintered at 850℃has good sinterability.7.To investigate if the relationship of different concentration of pigments and their reflective spectrums is fit to the computer color matching theory, the monochromatic samples with different concentrations of zirconate-based pigments were prepared by sintering technology. Their chroma values and reflective spectrums were measured and investigated. The result indicated that the relationship between the concentrations of pigments and the chroma values accorded with the principles of pigmentation color characteristic, and the spectral reflectivity of monochromatic samples were feasible for establishing database of computer-color-matching software.更多还原