低溫降解對快速燒結型氧化鋯光學性能的影響

The effect of low-temperature degradation on optical properties of quick sintering zirconia

黃薏紋(Yi-Wen Huang)

指導教授 ： 燕敏

中山醫學大學/口腔醫學院/口腔科學研究所/碩士(2021年)

https://doi.org/10.6834/csmu202100087

摘要

研究目的是評估低溫降解對於氧化鋯光學性能的影響，也評估老化對不同厚度的快速燒結型氧化鋯的半透明度(TP)、蛋白光參數(OP)、對比度(CR)和色差(ΔE)性能的影響。實驗使用六種氧化鋯陶瓷 (Copran Zri、Cercon ht、Copran Smile、Cercon xt、Copran Smile Symphony、Cercon xt ML)，試片尺寸為直徑12.0 mm，厚度為0.5與1.2 mm。依照廠商提供的燒結程式進行氧化鋯快速燒結(Quick sintering，QS)與傳統燒結(Conventional sintering，CS)。在溫度134 °C和壓力0.2 MPa環境下對各種條件的試片進行1、3及5個 小時的低溫降解處理。使用的牙科比色光譜儀(VITA Easyshade V)進行測量試片的L*、a*、b*值，以公式計算出TP、OP、CR和ΔE。以SEM觀察低溫降解前後各試片的表面微觀結構，用Image J軟體計算晶粒尺寸，以XRD分析晶相。實驗結果顯示所有試片老化後氧化鋯的表面結構與晶粒尺寸沒有明顯的改變，XRD分析顯示老化後只有CZI-CS燒結組會出現t→m的相轉變，以及無論在哪種燒結方式下CHT的t峰和CSS的c峰分別有半高寬變寬。在光學性質方面，3Y-TZP快速燒結型的氧化鋯試片經老化後的TP值與OP值，除了CHT厚度0.5 mm有明顯下降以外，其他都稍微下降，CR值則是沒有變化。5Y-TZP經過老化後的TP值，除了CML稍微上升以外，其他都稍微降低，CR值稍微升高。OP值只有CSS 0.5 mm的試片稍微降低，其餘5Y-TZP材料都稍微上升。增加6種材料的試片厚度，其TP值會降低，而CR值會升高，透明度降低。所有試片測得ΔE都小於2.6的可感知性閾值，老化後用肉眼都無法觀察到色差。本研究有限的實驗結果證明了低溫降解對快速燒結型氧化鋯光學性質沒有顯著的影響，且這些氧化鋯具有良好的抗老化性在臨床牙科中是可以使用的。

關鍵字

氧化鋯 ； 低溫降解 ； 快速燒結 ； 光學性質

並列摘要

The purpose of the research was to evaluate the influence of low-temperature degradation on the optical properties of zirconia, and to evaluate the influence of aging time on the translucency parameter (TP), opalescence parameter (OP), contrast ratio (CR) and color difference (ΔE) of quick sintering type zirconia ceramics with different thicknesses. Six kinds of zirconia ceramics (Copran Zri, Cercon ht, Copran Smile, Cercon xt, Copran Smile Symphony, Cercon xt ML) were used. The size of the specimen is 12.0 mm in diameter and 0.5 and 1.2 mm in thickness. The zirconia ceramics was sintered according to the manufacturer's quick sintering (QS) or conventional sintering (CS) procedure. The specimens in various conditions were subjected to low-temperature degradation for 1, 3 and 5 hours at 134°C and a pressure of 0.2 MPa. The dental colorimetric spectrometer (VITA Easyshade V) is used to measure the L*, a*, and b* values of the specimens, and TP, OP, CR and ΔE of the specimens are calculated by the formulas. The surface structure of the specimen before and after aging was observed using SEM, and then the grain size was calculated by Image J software. The crystal phase of the specimens before and after aging were analyzed by XRD. The experimental results showed that the surface structure and grain size of the zirconia did not change significantly after aging. The XRD results showed that only the CZI zirconia by CS showed t to m phase transition after aging. In addition, regardless of the sintering method, the peak width at half height became wider at the t peak of CHT and the c peak of CSS after aging, respectively. In this study, most of 3Y-TZP specimens by QS decreased slightly in TP and OP values, except the CHT specimen with thickness of 0.5 mm, which decreased significantly after aging. The CR values did not change. Most 5Y-TZP zirconia showed a slight decrease in TP value after aging, except for a slight increase in CML. As for the OP value, only the CSS specimen with 0.5 mm decreased slightly, while the TP of the other 5Y-TZP materials increased slightly. The CR values of the specimens showed a slight increase. The experimental results showed that with the increase the thickness of the specimens, the TP value decreased, while the CR value increased, and the transparency decreased. The ΔE of the specimens before and after aging is less than the perceptibility threshold of 2.6, and the color difference cannot be observed by the naked eye. The limited experimental results of this study suggested that low-temperature degradation has no significant effect on the optical properties of quick sintering type zirconia ceramics, and that these zirconia ceramics have good resistance to aging and can be used in clinical dentistry.

並列關鍵字

zirconia ； low-temperature degradation ； quick sintering ； optical properties

參考文獻

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