Department of Dental Laboratory Science and Engineering, College of Health Science, Korea University, Seoul, Republic of Korea.
J Adv Prosthodont. 2013 May;5(2):161-6. doi: 10.4047/jap.2013.5.2.161. Epub 2013 May 30.
This study aimed to identify the effects of the sintering conditions of dental zirconia on the grain size and translucency.
Ten specimens of each of two commercial brands of zirconia (Lava and KaVo) were made and sintered under five different conditions. Microwave sintering (MS) and conventional sintering (CS) methods were used to fabricate zirconia specimens. The dwelling time was 20 minutes for MS and 20 minutes, 2, 10, and 40 hours for CS. The density and the grain size of the sintered zirconia blocks were measured. Total transmission measurements were taken using a spectrophotometer. Two-way analysis of variance model was used for the analysis and performed at a type-one error rate of 0.05.
There was no significant difference in density between brands and sintering conditions. The mean grain size increased according to sintering conditions as follows: MS-20 min, CS-20 min, CS-2 hr, CS-10 hr, and CS-40 hr for both brands. The mean grain size ranged from 347-1,512 nm for Lava and 373-1,481 nm for KaVo. The mean light transmittance values of Lava and KaVo were 28.39-34.48% and 28.09-30.50%, respectively.
Different sintering conditions resulted in differences in grain size and light transmittance. To obtain more translucent dental zirconia restorations, shorter sintering times should be considered.
本研究旨在确定牙科氧化锆的烧结条件对晶粒尺寸和透明度的影响。
制作了两种商业品牌（Lava 和 KaVo）的各 10 个氧化锆样本，并在五种不同条件下进行烧结。使用微波烧结（MS）和常规烧结（CS）方法来制作氧化锆样本。MS 的停留时间为 20 分钟，CS 的停留时间为 20 分钟、2 小时、10 小时和 40 小时。测量烧结氧化锆块的密度和晶粒尺寸。使用分光光度计进行全透射测量。使用方差分析模型进行分析，误差率为 0.05。
品牌和烧结条件之间的密度没有显著差异。平均晶粒尺寸根据烧结条件增加，结果如下：两种品牌的 MS-20 分钟、CS-20 分钟、CS-2 小时、CS-10 小时和 CS-40 小时。Lava 的平均晶粒尺寸范围为 347-1512nm，KaVo 的平均晶粒尺寸范围为 373-1481nm。Lava 和 KaVo 的平均透光率值分别为 28.39-34.48%和 28.09-30.50%。
不同的烧结条件导致晶粒尺寸和透光率的差异。为了获得更透明的牙科氧化锆修复体，应考虑缩短烧结时间。
