Zhong Ying-chun, Lyu Shuai, Luo Peng, et al. Internal Defects Detection and Their Features Statistical Analysis of Porcelain Teeth[J]. 2018, 35(1): 1-5.
Zhong Ying-chun, Lyu Shuai, Luo Peng, et al. Internal Defects Detection and Their Features Statistical Analysis of Porcelain Teeth[J]. 2018, 35(1): 1-5.DOI: 10.12052/gdutxb.170091.
Internal Defects Detection and Their Features Statistical Analysis of Porcelain Teeth
Porcelain tooth is an ideal prosthesis of oral diseases. Limited by the fabrication process
there are always some internal defects in porcelain teeth
such as stomas
shrinkages and bubbles. These defects affect the service life and strength of porcelain teeth. It is proposed to scan the porcelain teeth by MicroCT. Then the defects can be displayed clearly through image processing. Subsequently
some features of defect are extracted
including areas and positions. Finally
the statistics of these features are analyzed in order to giveadviceto improve the fabrication process of porcelain teeth. The analysis results show that the distribution of area of internal defect obeys Weibull distribution
that is
the number of internal defects with large area is small but the number of internal defects with small areas is quite large. It reveals that most of defects are caused by porosity and shrinkage
which often result in small area defects. Additionally
the defects are mainly located at crown and joint surface
where the stress concentration is often located. Therefore
there are two methods to reduce the defects. One is reduce the stress concentration and the otherto improve the gas exit.
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references
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