抛光与上釉对牙科纳米陶瓷表面粗糙度的影响

目的比较抛光与上釉对纳米陶瓷表面粗糙度的影响。方法用纳米陶瓷粉(IMAGINEREFLEX)制备盘状试件40个,随机分为A、B两组。A组抛光组用240#~1500#碳化硅砂纸依次逐级打磨,最后用金刚砂抛光膏完成抛光。B组上釉组重新表面上釉。以粗糙度测试仪测试两组试件表面分别经抛光和表面上釉后表面粗糙度值并进行统计学分析,扫描电镜观察和评估样本表面形貌。结果纳米陶瓷IMAGENEREFLEX抛光组和上釉组表面粗糙度值无显著性差异(P>0.05);扫描电镜结果显示抛光组和上釉组表面无明显差异,均较为光滑,抛光组表面散在少量细小孔隙。结论对于纳米陶瓷的表面处理,抛光可以获得和重新上釉相同的表面光滑度。     

牙科陶瓷调磨后不同的抛光上釉方法对其表面性状的影响

目的牙科陶瓷调磨后比较不同的抛光上釉方式其表面的光泽度。方法 用V intage瓷粉制作盘状试件24个,均匀调磨后按不同的处理方式随机分成四组,以粗糙度测试仪测量各组的粗糙度值并进行统计学分析,体视显微镜和电子显微镜观察试件表面形貌。结果抛光和上釉表面粗糙度值无显著性差异（P〉0.05）;镜下观察四组试件表面结构及光滑度无明显差别。结论牙科陶瓷调磨后抛光可以达到与自身上釉相近似的效果。     

不同磨光方法对弹性义齿基托表面粗糙度影响的实验研究

目的:研究不同磨光处理对弹性义齿基托表面粗糙度的影响,为临床选择合适的磨光方法提供参考。方法:常规制作弹性基托试件90个,随机分为3组,分别采用硅橡胶磨头(1#-3#),金刚砂磨头(001#、002#),砂纸卷(500目、1000目、1500目)粗磨,采用布轮沾水,布轮沾抛光蜡,布轮沾抛光蜡和亮托抛光浆细磨抛光,利用表面粗糙度检查仪测定其粗糙度,扫描电镜观察磨光后的表面形貌,然后对检测结果进行统计学分析。结果:表面粗糙度检查仪检测:不同粗磨方法样本组的表面粗糙度(Ra值)的平均值比较:砂纸组<硅橡胶磨头组<金刚砂组,统计学上存在显著性差异(P<0.001);各组抛光方法表面粗糙度(Ra值)的平均值比较:布轮沾抛光膏和亮托抛光浆组<布轮沾抛光膏组<布轮沾水组,统计学上存在显著性差异(P<0.001)。扫描电镜观察:经金刚砂粗磨,试件表面粗糙,划痕较多,较深;经硅橡胶磨头粗磨,试件表面较光滑,划痕较浅;经1500目砂纸粗磨,试件表面最光滑,划痕最浅。经布轮沾水抛光,试件表面粗糙,划痕较多,较深;经布轮沾抛光蜡抛光,试件表面较光滑,划痕较浅;经布轮沾抛光蜡和亮托抛光浆抛光,试件表面最平滑。结论:经砂纸;硅橡胶磨头;金刚砂处理弹性义齿试件,获得不同的表面粗糙度,经1500目砂纸和硅橡胶磨头处理的试件表面平滑。经布轮沾抛光蜡,布轮沾亮托抛光浆抛光弹性义齿试件表面,表面粗糙度得到显著降低,试件表面平滑。弹性义齿试件不同的粗磨和抛光方法之间存在交互作用,经1500目砂纸粗磨和布轮沾抛光蜡和亮托抛光浆处理后,可以获得较低的粗糙度值,试件表面最平滑。     

纳米陶瓷与普通陶瓷表面粗糙度的对比研究

目的比较纳米陶瓷与普通陶瓷的表面粗糙度并探讨烧结次数对每种陶瓷的表面粗糙度的影响。方法根据瓷粉种类及烧结次数不同分为10组,每组5个。A～E组为普通陶瓷组,烧结次数依次为4、6、8、10、12次。A'～E'组为纳米陶瓷组,烧结次数分别与A～E组相对应。各组的烧结次数中均包括不透明瓷烧结2次,自身上釉烧结1次,其余为体瓷的烧结次数。采用2205型表面粗糙度仪分别测定每个试件的表面粗糙度值,求取每组试件的平均值。结果体瓷不同烧结次数处理后,纳米陶瓷的表面粗糙度值均明显小于普通陶瓷(P0.001),而每种陶瓷的表面粗糙度值均与体瓷烧结次数无关(P0.05)。结论纳米陶瓷较普通陶瓷表面光滑,经自身上釉烧结处理后,纳米陶瓷和普通陶瓷的体瓷烧结次数对其表面光滑度均无影响。     

振荡培养条件下氧化锆陶瓷和钛合金表面粗糙度与细菌黏附的比较

目的：振荡培养条件下比较氧化锆陶瓷和钛合金抛光后表面粗糙度的差异及变形链球菌在其表面的黏附能力。方法：制作氧化锆陶瓷和钛合金样本各6个。A组氧化锆陶瓷用EVE专用抛光轮高度抛光,B组钛合金原始铸件依次用粗砂纸、水砂纸（依次为200目、600目、800目、1000目、1200目、1500目、2000目）逐级磨光,再用抛光轮抛光。用表面粗糙度检测仪测量各组样本的表面粗糙度。将两组样本置于变形链球菌悬浮液中,37℃振荡培养条件下培养1h。荧光显微镜下计数黏附变形链球茵的数量,并通过扫描电子显微镜观察各样本的表面形貌。结果：A、B两组的表面粗糙度分别为（0．0548±0．027）μm、（0．0483±0．006）μm。变形链球菌在A、B两组样本表面的黏附数分别为4．2222±1．019、8．5417±2．208。经统计学分析,A、B两组表面粗糙度差异无显著性（P〉0．05）,A组与B组样本变形链球菌黏附数差异有显著性（P〈0．05）。扫描电镜显示,氧化锆陶瓷抛光组试件表面散在少量细小孔隙,而钛合金抛光组试件表面未见少量细小空隙,但有较多裂隙和凹陷。结论：氧化锆陶瓷和钛合金抛光后表面能达到同样光滑,但钛合金表面比氧化锆陶瓷表面更容易黏附变形链球茵。     

离子交换对常用牙科陶瓷表面增强效果的研究

目的 建立并探讨单重离子交换增强技术（HX－I型增强剂）对常用牙科陶瓷的增强效果。方法 制备Vita VMK95、Vita VMK68、Shofu Vintage标准试件各10条，将标准试件随机分组，实验组涂布HX－I型增强剂后，与空白对照组在相同条件下处理后，测定三点弯曲强度，并对实验组、对照组试件表面进行电子微探针分析（EMPA），观察Na^ →K^ 交换深度。结果经统计学分析，观察HX－I型增强剂的效果。结果 用HX－I型增强剂处理的陶瓷的三点弯曲强度明显增加，结果具有统计学意义（P＜0.05）；EMPA可见，自增强面至100μm深度以下K^ 明显增加而Na^ 明显下降。结论 HX－I寺强剂可使常用牙科陶瓷表面产生明显的Na^ →K^ 交换，并对常用牙科陶瓷弯曲强度有显著增强效果。     

五种抛光方法对玻璃陶瓷表面粗糙度的影响研究#br#

目的    比较临床上5种常用抛光方法对IPS e.max Press玻璃陶瓷调磨后表面粗糙度的影响。方法    选取临床常用修复材料IPS e.max Press玻璃陶瓷制作试件30个,随机分成6组（每组5个试件）,分别为对照组（常规上釉）、砂石组（绿色碳化硅砂石+氧化铝白砂石依次混合打磨抛光）、松风组（松风Ceramaster精细烤瓷砂石抛光）、EVE组（EVE氧化锆砂石抛光）、道邦组（道邦弹性瓷砂石抛光）、3M组（3M Sof-LexTM抛光套装）。常规调磨后按照各自不同的整体抛光打磨方法分别对试件表面依次进行抛光,扫描电镜下观察各组抛光后试件的表面形态,检测各组抛光后试件的表面粗糙度Ra值。结果　扫描电镜下观察可见3M组和道邦组抛光后试件表面较为平整光滑,划痕较少,与对照组类似;而砂石组和松风组试件表面划痕明显并伴有明显的凹坑;EVE组划痕较少且划痕条纹较平整,方向一致,有少许凹痕较对照组明显。各组抛光后试件的表面粗糙度Ra值由小到大顺序排列为：3M组［（0.207 ± 0.016）μm］、对照组［（0.208 ± 0.015）μm］、道邦组［（0.216 ± 0.025）μm］、EVE组［（0.315 ± 0.017）μm］、松风组［（0.375 ± 0.030）μm］、砂石组［（0.379 ± 0.017）μm］;砂石组、松风组、EVE组Ra值均明显大于对照组（均P < 0.05）,而3M组、道邦组与对照组之间的差异无统计学意义（P > 0.05）。结论　5种抛光方法均能有效改善玻璃陶瓷表面粗糙度,不同抛光方法对IPS e.max Press玻璃陶瓷的抛光效果有一定的差异,以3M Sof-LexTM抛光套装抛光效果较佳。     

离子交换与常用陶瓷表面增强技术的对比研究

目的 对比单重离子交换增强技术与常用牙科陶瓷表面增强技术的增强效果。方法 制备Vita VMK95，Shofu Vintage标淮试件各30个，将标准试件随机分3组，A组涂布HX—I型增强剂处理，B组进行自身上釉，C组进行表面抛光，分别测定三点弯曲强度。结果经统计学分析，对比不同处理方法的增强效果。结果 A组三点弯曲强度值高于B组，B组高于C组，结果具有统计学意义(p＜0.05)。结论 陶瓷表面离子交换表面增强效果好于自身上釉和表面抛光。     

Comparative study on the surface roughness of nano-ceramic and traditional ceramic

目的 比较纳米陶瓷与普通陶瓷的表面粗糙度并探讨烧结次数对每种陶瓷的表面粗糙度的影响.方法 根据瓷粉种类及烧结次数不同分为10组,每组5个.A～E组为普通陶瓷组,烧结次数依次为4、6、8、10、12次.A′～ E′组为纳米陶瓷组,烧结次数分别与A～E组相对应.各组的烧结次数中均包括不透明瓷烧结2次,自身上釉烧结1次,其余为体瓷的烧结次数.采用2205型表面粗糙度仪分别测定每个试件的表面粗糙度值,求取每组试件的平均值.结果 体瓷不同烧结次数处理后,纳米陶瓷的表面粗糙度值均明显小于普通陶瓷(P＜0.001),而每种陶瓷的表面粗糙度值均与体瓷烧结次数无关(P＞0.05).结论 纳米陶瓷较普通陶瓷表面光滑,经自身上釉烧结处理后,纳米陶瓷和普通陶瓷的体瓷烧结次数对其表面光滑度均无影响.     

不同抛光处理对粘结托槽的瓷表面粗糙度影响的体外研究

目的：探讨不同抛光处理方法对烤瓷表面粘结的托槽去除后,瓷表面抛光后粗糙度的影响。方法：采用不同方法粘结托槽：A组（氢氟酸＋陶瓷偶联剂＋釉质粘结剂）;B组（氢氟酸＋釉质粘结剂）;C组（陶瓷偶联剂＋釉质粘结剂）。烤瓷片表面不同方法粘结托槽经剪切去除后,测定瓷面采用不同步骤抛光处理前后及对照组的瓷片表面粗糙度值。结果：抛光前A、B组间差异无统计学意义（P＞0．05）,C组小于A、B组,差异有统计学意义（P＜0．05）;抛光过程中各组间差异无统计学意义（P＞0．05）;各组抛光前后比较差异有统计学意义（P＜0．01）;抛光后各组间比较差异无统计学意义（P＞0．05）,都达到了对照组水平（P＞0．05）。结论：机械打磨、氢氟酸、陶瓷偶联剂对瓷表面粗糙度的影响依次递减,抛光套装依序抛光对降低表面粗糙度行之有效,抛光后能使托槽去除后瓷表面粗糙度达到对照组水平。     

烤瓷表面处理方式对其黏结性能影响的研究

目的:研究不同偶联剂结合不同瓷表面粗化处理对V ita VMK95瓷黏结强度的影响趋势。方法:瓷片按偶联剂分为3大组,每大组再按瓷表面粗化方式分为6小组。每组分别与树脂黏结,测剪切强度,统计分析所得数据。结果:三种偶联剂结合6种表面粗化方式处理后,瓷与树脂的黏结强度都以喷砂后用氢氟酸处理组最高,单纯偶联剂处理组最低。结论:三种偶联剂与不同瓷表面粗化处理组合对V ita VMK95瓷与树脂的黏结强度影响趋势是一致的,都以喷砂后氢氟酸处理组最高。     

Structural reliability of alumina-, feldspar-, leucite-, mica- and zirconia-based ceramics

OBJECTIVES: The objective of this study was to test the hypothesis that industrially manufactured ceramic materials, such as Cerec Mark II and Zirconia-TZP, have a smaller range of fracture strength variation and therefore greater structural reliability than laboratory-processed dental ceramic materials. METHODS: Thirty bar specimens per material were prepared and tested. The four-point bend test was used to determine the flexure strength of all ceramic materials. The fracture stress values were analyzed by Weibull analysis to determine the Weibull modulus values (m) and the 1 and 5% probabilities of failure. RESULTS: The mean strength and standard deviation values for these ceramics are as follows: (MPa+/-SD) were: Cerec Mark II, 86.3+/-4.3; Dicor, 70.3+/-12.2; In-Ceram Alumina, 429. 3+/-87.2; IPS Empress, 83.9+/-11.3; Vitadur Alpha Core, 131.0+/-9.5; Vitadur Alpha Dentin, 60.7+/-6.8; Vita VMK 68, 82.7+/-10.0; and Zirconia-TZP, 913.0+/-50.2. There was no statistically significant difference among the flexure strength of Cerec Mark II, Dicor, IPS Empress, Vitadur Alpha Dentin, and Vita VMK 68 ceramics (p>0.05). The highest Weibull moduli were associated with Cerec Mark II and Zirconia-TZP ceramics (23.6 and 18.4). Dicor glass-ceramic and In-Ceram Alumina had the lowest m values (5.5 and 5.7), whereas intermediate values were observed for IPS-Empress, Vita VMK 68, Vitadur Alpha Dentin and Vitadur Alpha Core ceramics (8.6, 8.9, 10.0 and 13.0, respectively). CONCLUSIONS: Except for In-Ceram Alumina, Vitadur Alpha and Zirconia-TZP core ceramics, most of the investigated ceramic materials fabricated under the condition of a dental laboratory were not stronger or more structurally reliable than Vita VMK 68 veneering porcelain. Only Cerec Mark II and Zirconia-TZP specimens, which were prepared from an industrially optimized ceramic material, exhibited m values greater than 18. Hence, we conclude that industrially prepared ceramics are more structurally reliable materials for dental applications although CAD-CAM procedures may induce surface and subsurface flaws that may adversely affect this property.     

Polishing and coating of dental ceramic materials with 308 nm XeCl excimer laser radiation.

OBJECTIVES: The polishing and coating of ceramic surfaces is recommended in order to improve the physical properties of dental ceramics. Conventional methods for the surface treatment of dental ceramic materials are not capable of creating a smooth surface without microcracks. The special radiation characteristics of XeCl excimer laser light indicate that it must be possible to treat ceramic surfaces in order to produce a polished finish. The aim of this study was to investigate the efficacy of XeCl excimer laser radiation for the polishing and coating of dental ceramics. METHODS: Samples (n = 64) of four different dental ceramic materials were irradiated with 308 nm XeCl excimer laser radiation at varying energy densities per laser pulse of 1.57, 3.14, and 6.28 J cm-2. In detail, the subjects for irradiation were samples of Ivoclar-Empress (leucite-reinforced feldspathic ceramic), In-Ceram Spinell (double crystalline spinell ceramic), In-Ceram Alumina (alumina oxide; continous interpenetrating phase composite ceramic) and Vita-Mark II (feldspathic ceramic). The roughness (Ra) of the laser-treated ceramic surfaces was measured using a profilometer. In addition, SEM and AFM investigations of the changes in surface structure were conducted. The changes in surface roughness due to laser treatment were analyzed for their statistical significance using ANOVA with the Scheffé test at a level of significance of 0.05% (p < 0.05). Depending on the type of ceramic material and the energy density of the radiation, varying reductions of the surface roughness were obtained. In general, minimum values of the roughness were measured on samples irradiated with maximum energy density of radiation. RESULTS: The lowest roughness value was obtained for the specimen of In-Ceram Spinell: 1.30 (+/- 0.19) microns. The mean value for minimal roughness of Ivoclar-Empress was 1.92 (+/- 0.35) microns, that for In-Ceram Alumina was 2.04 (+/- 0.49) microns, and that for Vita-Mark II was 2.72 (+/- 0.40) microns. Ultrastructural examination of laser-treated ceramics in part demonstrated both extensive fusion and inhomogeneous surfaces with blistering and the formation of microcracks. SIGNIFICANCE: It is concluded that the physical roughness of dental ceramic surfaces can be significantly reduced by 308 nm excimer laser irradiation. Nevertheless, the laser-treated surface was in no case completely fused and the formation of microcracks and blistering was observed. Therefore, after using an XeCl excimer laser for finishing dental ceramic alloys, further polishing of the laser-treated ceramic surfaces will be needed.     

Surface roughness of five different dental ceramic core materials after grinding and polishing

In clinical practice, core materials can be exposed after adjustments are made to previously-luted all-ceramic restorations. The purpose of this study was to evaluate the surface roughness of five different dental ceramic core materials after grinding and polishing. Five different ceramic core materials, Vita In-Ceram Alumina, Vita In-Ceram Zirconia, IPS Empress 2, Procera AllCeram, and Denzir were evaluated. Vita Mark II was used as a reference material. The surface roughness, Ra value (mum), was registered using a profilometer. The measurements were made before and after grinding with diamond rotary cutting instruments and after polishing with the Sof-Lex system. The surface of representative specimens was evaluated qualitatively using scanning electron microscopy (SEM). Results were statistically analysed using analysis of variance (anova) supplemented with Scheffè's and Bonferroni multiple-comparison tests. Before grinding, Procera AllCeram and Denzir had the smoothest surfaces, while IPS Empress 2 had the coarsest. After grinding, all materials except IPS Empress 2 became coarser. Polishing with Sof-Lex provided no significant (P > 0.05) differences between Denzir, Vita Mark II and IPS Empress 2 or between Procera AllCeram and In-Ceram Zirconia. There were no significant differences (P > 0.05) either between the ground and the polished Procera AllCeram or In-Ceram Alumina specimens. Polishing of Denzir, IPS Empress 2 and In-Ceram Zirconia made the surfaces smoother compared with the state after grinding, whereas the polishing effect on Procera AllCeram and In-Ceram Alumina was ineffective. The findings of the SEM evaluation were consistent with the profilometer readings.     

Effects of different concentrations of carbamide peroxide and bleaching periods on the roughness of dental ceramics

The wide use of dental bleaching treatment has brought concern about the possible effects of hydrogen peroxide on dental tissue and restorative materials. The objective of this study was to evaluate in vitro the effect of nightguard bleaching on the surface roughness of dental ceramics after different periods of bleaching treatment. Fifteen specimens of 5 × 3 × 1 mm were created with three dental ceramics following the manufacturers' instructions: IPS Classic (Ivoclar-Vivadent); IPS d.Sign (Ivoclar-Vivadent); and VMK-95 (Vita). A profilometer was used to evaluate baseline surface roughness (Ra values) of all ceramics by five parallel measurements with five 0.25 mm cut off (Λc) at 0.1 mm/s. Afterwards, all specimens were submitted to 6-h daily bleaching treatments with 10% or 16% carbamide peroxide (Whiteness- FGM) for 21 days, while control groups from each ceramic system were stored in artificial saliva. The surface roughness of all groups was evaluated after 18 h, 42 h, 84 h, and 126 h of bleaching treatment. The surface roughness of each specimen (n = 5) was based on the mean value of five parallel measurements in each time and all data were submitted to two-way repeated measures ANOVA and Tukey's post-hoc test (α = 0.05). No significant differences in ceramic surface roughness were observed between untreated and bleached ceramic surfaces, regardless of bleaching intervals or bleaching treatments. This study provided evidence that at-home bleaching systems do not cause detrimental effects on surface roughness of dental ceramics.     

Physical properties and microstructural characterization of dental porcelains mixed with distilled water and modeling liquid.

OBJECTIVE: The aim of this study was to microstructurally characterize and to make comparisons of the physical properties of sintered dental porcelains prepared by mixing with distilled water and with their modeling liquid. METHODS: Six commercial porcelain powders: IPS Classic (Ivoclar Vivadent AG, Schaan, Liechtenstein), IPS d.SIGN (Ivoclar Vivadent AG), IPS InLine (Ivoclar Vivadent AG), Vita VMK95 (Vita Zahnfabrik, Bad Sackingen, Germany), Vita OMEGA 900 (Vita) and Ceramco III (Ceramco-Dentsply, Burlington, NJ, USA) were used as starting powders. Following particle size and BET analyses of starting powders, each porcelain powder was mixed with distilled water and with its own modeling liquid. Disc specimens were sintered in accordance with each manufacturer's instructions. Specimens were characterized using X-ray diffraction (XRD), optical microscopy and SEM analysis and their physical properties such as bulk density, microhardness and biaxial flexural strength were determined. RESULTS: The sintered dental porcelains premixed with modeling liquid had density, biaxial flexural strength and microhardness values slightly higher than those premixed with distilled water. Mixing with distilled water and modeling liquid caused statistically significant differences between the density values of Vita VMK 95 and microhardness values of IPS d.SIGN and IPS InLine. Characterization investigations (XRD and SEM) revealed the coexistence of the tetragonal leucite (1-3 microm) and hexagonal fluorapatite crystals (0.4-1.2 microm) in a feldspathic glassy matrix in the microstructure of IPS d.SIGN and only leucite crystals (3-6 microm) in the microstructures of other porcelains. SIGNIFICANCE: Mixing the porcelain powders with distilled water or modeling liquid prior to sintering has no effect on the resultant sintered crystalline microstructure. On the other hand, significant differences exist between the physical properties of some porcelains.