Effects of Surface Treatments on Degradation of Zirconia Using Glass as Additive

• Main Authors: Li-Chun Wang, 王理駿
• Other Authors: Shih-Ching Wu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/24637742458143628170

碩士 === 中臺科技大學 === 醫學工程暨材料研究所 === 99 === Yttria-Tetragonal Zirconia Polycrystal (Y-TZP) is a preference material in dentistry owing to its good mechanical properties and excellent biocompatibility. The A-A (MgO - CaO - Al2O3 - SiO2 - P2O5) glass powder has been introduced as additive of Y-TZP to lower the sintering temperature via liquid-phase sintering. The influence of glass additive on sintering and mechanical properties has been studied. The aim of this study is to evaluate the degradation and biocompatibility of zirconia through using glass as additive. The effects of surface treatments will be studied as well. Y-TZP specimens with 0, 1, 3, 5, and 10 wt% A-A glass frits were sintered at 1300℃. The evaluation of low temperature degradation of zirconia has been assessed by determining the decreasing of mechanical strength, roughening of the surface, changing of the phase, and releasing of the ions. Biocompatibility was evaluated by using L929 fibroblast cell for cytotoxicity and MG-63 osteoblastic cell for osteointegration, respectively. The results revealed that phase transformation increased with the quantities of adding glass frits. After 7 days immersing, Y-TZP with 10% glass frits would have 35% phase transformation, while Y-TZP without glass frits only has 1%. With grinding treatment, the transformation of Y-TZP with 10% glass frits significantly decreased (35% → 21%), in contrast to Y-TZP without glass frits increased (1% → 8%). With sandblast treatment, Y-TZP without glass frits would have the highest transformation (44%). These results display that surface treatments on Y-TZP using A-A glass as additive would decrease the amount of transformation. Biocompatibility results also indicate that A-A glass powder has no cytotoxicity. The Ca and Si elements in A-A glass promote the osteointegration.