Recently, more and more researchers pay attention to the study on the microwave use for the ceramic sintering because unlike traditional sintering method which uses electric furnace, microwave sintering method employs internal and volumetric heating p...
Recently, more and more researchers pay attention to the study on the microwave use for the ceramic sintering because unlike traditional sintering method which uses electric furnace, microwave sintering method employs internal and volumetric heating process of the specimen itself. As the time for the microwave sintering process gets shortened, the size of the particle growth also become reduced. Lessened particle size makes microstructure more even and compact condition and enhances fracture strength.This research applied microwave sintering method to zirconia core which has been implemented along with the introduction of recent CAD/CAM system. Because shrinkage usually takes place and affects sintered core in the process of sintering in terms of generic electricity furnace and microwave, understanding these interaction is beneficial.Firstly, 12 cores for each group were made by using each different sintering process and attached them to a metal die with silicon.Secondly, after the internal and marginal gap of sintered zirconia was measured by using Skyscan 1076 micro-CT, it reorganized BMP files against each samples by means of CT-An software and transformed FeldKamp algorithm. To each samples, we extracted B-L image, M-D image of cutting side, and cross-sectional side of tooth long axis and calculated the mean value of marginal, axial, and occlusal gap each side.Finally, the research statistically analyzed final results acquired from each groups in terms of one-way ANOVA method.From this experimental research, the study constituted important meaningful outputs as follows.1. The mean marginal gap of sintered zirconia was 36.20μm for EVE, 47.67μm for LAV, 52.47μm for DEN, and 54.63μm for CER.2. For the axial wall, the research showed the largest value of 63.49um for EVE whereas DEN and CER were similar in value. Among four groups, there were no significant level to be able to decline the null-hypothesis.3. In related to the occlusal internal measurement, the study demonstrated that CER was the largest value, 195.47μm and DEN was the smallest value,77.06um. EVE and CER showed significant value.This research has shown that CAD/CAM zirconia core which was made in the process of microwave sintering has clinically acceptable values in marginal and internal gap.