Wei-Chi Chen , Shu-Fen Chuang , Po-Chun Tseng , Ting-Weng Lai , Terry Yuan-Fang Chen , Yung-Nien Sun
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引用次数: 0
Abstract
Objective
To investigate the feasibility of optical coherence tomography (OCT)-based digital image correlation (DIC) analysis and to identify the experimental parameters for measurements of polymerization shrinkage.
Methods
Class I cavities were prepared on bovine incisors and filled with Filtek Z350XT Flowable (Z350F). One OCT image of the polymerized restoration was processed to generate virtually displaced images. In addition, the tooth specimen was physically moved under OCT scanning. A DIC software analyzed these virtual and physical transformation sets and assessed the effects of subset sizes on accuracy. The refractive index of unpolymerized and polymerized Z350F was measured via OCT images. Finally, different particles (70–80 µm glass beads, 150–212 µm glass beads, and 75–150 µm zirconia powder) were added to Z350F to inspect the analyzing quality.
Results
The analyses revealed a high correlation (>99.99%) for virtual movements within 131 pixels (639 µm) and low errors (<5.21%) within a 10-µm physical movement. A subset size of 51 × 51 pixels demonstrated the convergence of correlation coefficients and calculation time. The refractive index of Z350F did not change significantly after polymerization. Adding glass beads or zirconia particles caused light reflection or shielding in OCT images, whereas blank Z350F produced the best DIC analysis results.
Significance
The OCT-based DIC analysis with the experimental conditions is feasible in measuring polymerization shrinkage of RBC restorations. The subset size in the DIC analysis should be identified to optimize the analysis conditions and results. Uses of hyper- or hypo-reflective particles is not recommended in this method.
期刊介绍:
Dental Materials publishes original research, review articles, and short communications.
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The principal aim of Dental Materials is to promote rapid communication of scientific information between academia, industry, and the dental practitioner. Original Manuscripts on clinical and laboratory research of basic and applied character which focus on the properties or performance of dental materials or the reaction of host tissues to materials are given priority publication. Other acceptable topics include application technology in clinical dentistry and dental laboratory technology.
Comprehensive reviews and editorial commentaries on pertinent subjects will be considered.