铝瓷核烧结长石质瓷前后贴面颜色的变化

目的：考察Procera铝瓷核表面烧结长石质饰面瓷形成双层瓷贴面前后的颜色变化。方法：应用自凝树脂和着色材料制作模仿变色牙灰色的底质，15个氧化铝圆盘随机分为3个组，每组5个标本，分别 烧A1、A2、B43种颜色的长石质陶瓷，应用美能达CR－321色度仪测量底质上氧化铝圆盘烧结长石质饰面前后 的颜色变化，并以白色背景作为对照。结果：烧结长石质饰面瓷后颜色变化差异存在显著性（P＜0．01），加入A1、A2、B4饰面陶瓷后，△E从A1（2．311）、A2（4．313）到B4（8．778）逐渐增加；△L^*从A1（－1．530）、A2（－3．369）到B4（－3．358）逐渐减小；△b从A1（－1．440）、A2（2．198）到B4（7．955）逐渐增加，颜色变化方向与已往报道一致并受背景颜色的影响。结论：可通过在氧化铝核表面烧结长石质饰面瓷来调整瓷 贴面颜色。     

Subjective evaluation of the effect of porcelain opacity on the resultant color of porcelain veneers

The effect of porcelain veneer opacity on the resultant shade of a veneer/substrate system was subjectively evaluated. Three groups of porcelain discs were fabricated using shade A1 Ceramco G veneer porcelain diluted with 0%, 25%, or 50% translucent porcelain. The discs were luted to a shade C4 substrate using an untinted composite resin luting agent. Clinicians were instructed to match samples with a custom and a commercial shade guide, and to sort veneers into groups of similar shade. The Farnsworth-Munsell 83 Hue test was used to measure the clinicians' color vision. Results indicated that the participants were unable to distinguish any difference between veneer groups (kappa = 0.33). Shade C2 was the predominant shade chosen for all groups. All veneers provided some masking of the underlying substrate. Varying the percentage of translucent porcelain had little effect on the final shade assessment.     

Double-layer color effects in porcelain systems

The color of an unshaded body porcelain was determined at three thicknesses on white, gray, and three chromatic backings. Spectral absorption and scattering coefficients of the porcelain were determined from the diffuse reflectance at one thickness on the white and gray backings. These optical coefficients, when utilized with the Kubelka-Munk reflectance theory, accurately predicted the color of the other sample configurations studied. The scattering of the body porcelain was found to decrease with increasing wavelength within the visible spectrum, in accordance with scattering theory for particles not substantially less than the wavelength of the scattered light. For the filtering effects of a translucent material in optical contact with a backing, the Kubelka-Munk reflectance theory described the interaction between the optical absorption and scattering within the translucent material and the reflectance of the backing.     

Colorimetric evaluation of the effect of porcelain opacity on the resultant color of porcelain veneers.

The effect of porcelain veneer opacity on the resultant shade of a veneer-substrate system was evaluated colorimetrically. Three groups of porcelain discs were fabricated using shade A1 Ceramco G veneer porcelain diluted with 0%, 25%, or 50% translucent porcelain. The discs were luted to a shade C4 substrate using an untinted resin composite luting agent. A custom shade guide was fabricated. All samples were analyzed with a Chrome Meter using Munsell and CIE LAB notation. ANOVA showed significant differences (P less than .05) for each coordinate in both the Munsell and CIE LAB color space for all groups. The smallest delta E*ab for all groups was noted with shade tab C2. The resultant shade was neither the shade of the porcelain (A1) nor the substrate (C4). The data indicate that the translucent porcelain has as great or greater effect on the color coordinates of the veneer-substrate system as the substrate material.     

瓷层厚度对Vita饰面瓷颜色和半透性的影响

目的 探讨瓷层厚度对饰面瓷颜色和半透性的影响。方法制作Vita体瓷和釉瓷试件各5个，起始厚度为1．2mm，逐渐打磨至1．0、0．8、0．6、0．4、0．2mm，用PR-650光谱扫描色度仪分别测量每种厚度时的光谱积分透射率（T）和L^＊a^＊b^＊参数，计算色差和透射率差。结果L^＊值随着厚度的降低而升高，a^＊、b^＊随着厚度的降低而降低。透射率随着厚度降低而明显增加，呈指数关系。结论 饰面瓷的厚度对颜色和半透性均有显著影响。     

核饰瓷厚度和树脂水门汀对玻璃陶瓷贴面乳光性能的影响

目的　分析不同瓷层厚度和树脂水门汀对玻璃陶瓷贴面修复变色牙乳光性能的影响。方法　采用计算机辅助设计与计算机辅助制造（CAD/CAM）工艺制作IPS e.max CAD LT A3瓷贴面试件,核瓷组厚度分别为0.25 mm和0.50 mm;核瓷/饰瓷组厚度为0.25 mm核瓷/0.25 mm牙本质瓷、0.50 mm核瓷/0.25 mm牙本质瓷、0.50 mm核瓷/0.50 mm牙本质瓷和0.50 mm核瓷/0.25 mm牙本质瓷/0.25 mm切端瓷。模拟瓷贴面临床粘接程序,在CAD/CAM瓷贴面试件底部涂布Variolink N Bleach XL水门汀,制作CAD/CAM瓷贴面-树脂水门汀复合试件。利用分光光度计测试试件在反射和透射模式下色度值,并计算乳光值。结果　0.25 mm、0.50 mm核瓷组和0.25 mm核瓷/0.25 mm牙本质瓷、0.50 mm核瓷/0.25 mm牙本质瓷、0.50 mm核瓷/0.50 mm牙本质瓷、0.50 mm核瓷/0.25 mm牙本质瓷/0.25 mm切端瓷瓷贴面试件乳光值分别为6.10±0.50、7.00±0.24、6.40±0.24、7.08±0.28、7.16±0.21、7.81±0.11。随着核瓷厚度增加,乳光值显著增大（P<0.05）;核瓷厚度相同,增加0.25 mm牙本质瓷,乳光值的差异无统计学意义（P>0.05）。对于0.5mm核瓷组,牙本质瓷厚度从0.25 mm增加至0.5 mm,乳光值差异无统计学意义（P>0.05）,但增加0.25 mm切端瓷后乳光值显著增大（P<0.05）。0.25 mm核瓷/0.25 mm牙本质瓷、0.50 mm核瓷/0.25 mm牙本质瓷、0.50 mm核瓷/0.50 mm牙本质瓷和0.50 mm核瓷/0.25 mm牙本质瓷/0.25 mm切端瓷CAD/CAM瓷贴面-树脂水门汀复合体试件的乳光值分别为6.29±0.31、7.56±0.36、7.67±0.30、8.65±0.53,随瓷层厚度增加乳光值增大（P<0.05）,但0.50 mm核瓷/0.25 mm牙本质瓷和0.50 mm核瓷/0.50 mm牙本质瓷组间差异无统计学意义（P=0.733）。瓷层厚度和树脂水门汀对试件乳光值的影响均有统计学差异（P<0.05）,总厚度与有无树脂水门汀间无交互作用（P>0.05）。结论　玻璃陶瓷贴面修复变色牙时,为提高其乳光性能获得自然逼真的修复效果,推荐采用核瓷表面烧结切端瓷的设计,同时可适当增加核瓷厚度,选择具有遮色效果的树脂水门汀。     

陶瓷材料对瓷贴面颜色的影响

目的研究两类三种陶瓷材料对瓷贴面修复颜色的影响,为临床工作中瓷贴面修复体与比色板的颜色匹配性提供指导。方法制作直径10mm、厚度0.7mm的A2色瓷贴面圆盘试件,按陶瓷材料及制作工艺分为无遮色长石质烤瓷组、遮色长石质烤瓷组、IPSe.maxPress铸瓷组3组。每组10个试件,共计30个试件。选择Natural Die Material Shade Guide比色板中的ND4、ND6、ND8三种颜色,分别代表轻、中、重度变色牙底色,采用对应颜色树脂各制作1个底色圆盘。对每个瓷贴面试件分别以3种底色圆盘为基牙底色,采用Vita Easyshade电脑比色仪测量瓷贴面修复体的色度值。计算各组瓷贴面修复体与标准比色片A2的色差。结果在轻、中、重度变色牙背景条件下,两种陶瓷材料的瓷贴面修复体与标准比色片A2间色差的比较结果为,IPS e.max Press铸瓷组<无遮色长石质烤瓷组<遮色长石质烤瓷组,差异有统计学意义(P<0.05)。结论采用长石质烤瓷贴面及IPS e.max Press热压铸瓷贴面模拟修复不同程度的变色牙时,热压铸瓷贴面与标准比色片的颜色匹配性高于长石质烤瓷贴面。     

超薄贴面与常规贴面临床对比研究

目的：比较超薄贴面与常规贴面的临床效果,为超薄贴面的临床应用提供依据。方法选取超薄贴面20例与常规贴面修复患者45例,基牙分别为72、120颗,3、6、12、24、36个月后随访,依据改良美国公共卫生署贴面评价分类标准进行临床效果对比研究,统计留存率和成功率。结果经过3年观察,超薄贴面和常规贴面在继发龋、边缘适合性、边缘变色、颜色适合性和结构形态方面均有较好的临床表现,留存率及成功率均大于90%,经连续性校正卡方检验差异均无统计学意义（P>0.05）。结论超薄贴面可以获得与常规贴面相近的临床效果。     

温度变化对瓷贴面黏结剂颜色影响的实验研究

目的：研究温度变化对3种瓷贴面黏结剂颜色稳定性的影响。方法：用Vita T4透明瓷制作直径为10．0mm，厚为0．50mm的试件30个，随机分成A、B、C3组，A组采用EB化学固化黏结剂，B组采用RelyX Veneer光固化黏结剂，C组采用RelyX ARC双重固化黏结剂，均与玻璃底座黏结。然后用分光光度仪测境冷热循环前后的L^＊a^＊b^＊值，结果采用SPSS 10．0软件分析，比较3种黏结剂的颜色稳定性。结果：冷热循环前、后，A、B、C3组各自的L^＊a^＊b^＊值均有显著性差异（P〈0．05），平均△E值分别为3．10、1．41和1．43。与冷热循环前相比，3组的明度L^＊值均有显著降低，a^＊、b^＊值则有所增高。结论：EB化学固化黏结剂因颜色变化过于明显而不适宜做贴面黏结剂；RelyX veneer光固化黏结剂和RelyX ARC双重固化黏结剂虽然会发生一定的变色，但是基本能够满足临床美学要求。     

烤瓷贴面治疗变色牙的临床疗效

目的：观察烤瓷贴面治疗变色牙的临床疗效。方法：应用烤资面法治疗116个变色牙;并以复合树脂贴面治疗106个变色牙作对照。跟踪观察2年,比较其临床效果。结果：按颜色、外形、功能、感觉进行检查,用烤瓷贴面治疗者2年疗效优于84牙（72．4％）,一般32牙（27．6％）。用复合树脂治疗者2年疗效优66牙（62．26％）,一般25牙（23．58％）,失败15牙（14．15％）。结论：烤瓷贴面治疗变色牙的2年临床疗效较复合树脂贴面好,但远期疗效有待进一步研究。     

Final cementation of porcelain veneers

The method for cementation as described is similar to many other methods previously documented, however, in this case the addition of using the floss prior to tacking the veneers in place saves a great amount of time. If done properly it should be a rare necessity to have to saw contacts open because of accumulated cement (Figure 6).     

Color characterization of porcelain veneers.

Porcelain veneers have become a popular treatment modality in recent years. A common problem associated with these restorations is the inability of the dentist to reproduce the polychromatic appearance of a natural tooth with a porcelain veneer. It is the purpose of this article to describe several methods that may be used to transform a monochromatic porcelain veneer into a polychromatic restoration that approaches the beauty of a natural tooth.     

Clinical evaluation of etched porcelain veneers

This study evaluated 115 etched porcelain laminate veneers placed by a single operator at New York University Dental Center between 1982 and 1985. The restorations were divided into two groups. Group I consisted of 43 restorations placed without any tooth preparation; Group II consisted of 72 restorations placed using a chamfer preparation. The U.S.P.H.S. criteria was used to record cavosurface marginal discoloration, marginal integrity, and presence of caries. A clinical examination also revealed the number of debonds and/or the number of fractures of porcelain. A periodontal evaluation included the use of baseline and recall stone replicas of restored teeth to measure the height of the free gingival margin taken mid-facial to the incisal edge of the restoration. Any changes in gingival contour were also noted. Plaque and gingival indices were also recorded. The low fracture and debond rate found in the study combined with no incidence of caries seem to indicate that these restorations are functioning satisfactorily and with minimal negative periodontal response.     

The effect of porcelain laminate veneers on gingival health and bacterial plaque characteristics

Abstract. The aim of this study was to evaluate the response of microbial plaque and gingival inflammation to the placement of porcelain laminate veneers on anterior teeth. 9 patients, 7 female and 2 male (mean age of 30 years), with a total of 35 veneers were examined. The volume of gingival crevicular fluid (GCF), level of neutral proteolytic enzyme activity, gingival index (GI), plaque index (PII) and plaque bacteria vitality were measured at baseline and after the placement of veneers. The volume of GCF increased after the placement of veneers ( p =0.03). No statistically significant differences were found in proteolytic enzyme activity or GI ( p >0.05). There were statistically significant reductions in PII ( p =0.000) and plaque bacteria vitality ( p =0.018). Further research is required to assess the long-term influence of porcelain laminate veneers on gingival health and microbial plaque characteristics.     

全瓷贴面修复的临床效果评估

目的评价全瓷贴面修复后的临床疗效。方法对完成修复1~8年的25例患者133个贴面进行复查,对修复体边缘适合性、边缘染色、继发龋、颜色匹配、解剖形态、牙髓活力、隐裂、折断和脱落9项指标进行评估。以绝对失败贴面数来描述存留率,用绝对失败和相对失败的贴面总数来描述成功率,寿命表法计算全瓷贴面1~8年的存留率和成功率。结果全瓷贴面1~8年存留率分别为100.0%、99.2%、97.6%、96.7%、94.7%、93.2%、89.3%和89.3%,1~8年成功率分别为100.0%、98.5%、96.1%、94.4%、90.5%、84.5%、80.9%和80.9%。结论全瓷贴面近期和远期的修复效果良好。