GI-Ⅱ型渗透陶瓷全瓷底层材料透射率的测定

Spectral Transmittance of GI-Ⅱ Glass/Alumina Composite

目的 :探讨GI_Ⅱ型渗透陶瓷底层材料的透光率及材料颜色、厚度、不同玻璃渗透烧烤工艺对透光率的影响规律。方法 :制作直径为 12 5mm ,厚度分别为 0 5、1 0、1 5mm的GI_Ⅱ渗透陶瓷及VitaIn_CeramAlumina样本 ;另制作 0 5mm厚的样本 ,按 5个不同的渗透时间和 3个不同的渗透温度分组 ,以上每组的样本数目均为 3个。用分光光度计测量各组的可见光积分透射率 (标准A光源 ,光束直径 5mm ,波长范围 380～ 780nm)。结果 :GI_Ⅱ型渗透陶瓷材料的透射率范围为 2 7%～ 4 5 % ,VitaIn_CeramAlumina材料为 2 4%～ 5 2 % ;随样本颜色饱和度值的增加及明度值降低 ,透射率也降低 ;同种颜色样本随厚度增加透射率下降 ;透射率随渗透烧烤时间的延长呈增大趋势 ,6h以后则下降 ;随渗透温度升高 ,VitaIn_CeramAlumina的透射率下降 ,GI_Ⅱ渗透陶瓷材料则增加。结论 :GI_Ⅱ渗透陶瓷底层材料具有较好的透光性能。因渗透烧烤工艺、颜色及厚度对透射率有影响 。

Objective:The purposes of this study were to determine the spectral transmittance of GI-Ⅱglass/alumina composites and to explore the effects of different specimen thickness and firing arts of glass infiltration on the transmittance. Data were compared with those of Vita In-Ceram Alumina materials.Methods: Plate-shaped specimens 12.5 mm in diameter, with 3 thickness (0.5, 1.0, 1.5 mm), 6 color groups for GI-Ⅱand 4 color groups for Vita In-Ceram Alumina were fabricated. Specimens of color AL2 for In-Ceram and IG2 for GI-Ⅱ were selected in the study of relationship between different infiltration arts and transmittance. Five infiltration time duration and three temperatures were studied. A spectrophotometer with standard A light source paralleled light beam 5 mm in diameter and spectra range 380～780 nm was employed to measure the spectral transmittance.Results: The range of spectral transmittance were 2.7%～4.5% for GI-Ⅱand 2.4%～5.2% for Vita In-Ceram Alumina. Transmittance decreased with specimen thickness, but they were not linearly related. Transmittance of GI-Ⅱtended to increase and that of Vita In-Ceram Alumina decreased as the infiltration temperature elevated. The transmittance increased with infiltration time less than 4 hours and reduced with prolonged time over 6 hours for both materials.Conclusion: GI-Ⅱglass/alumina composite has comparatively lower translucency. Influences of factors as color, thickness and infiltration arts on translucency of restorations should be considered in the clinical selection of the all-ceramic materials.