Study opens possibilities for quantitative analysis of fracture propagation
Research conducted at Universidade Federal de Pernambuco in Recife, Brazil analysed the images sites of fracture initiation and slow crack propagation in a fiber reinforced composite using optical coherence tomography (OCT). Drs Ana Braz and Anderson Gomes from the university’s Graduate Programme in Odontology, concluded that OCT images provide a superior insight into crack propagation, which cannot be seen by the naked eye. By using OCT the possibility of analyzing fracture propagation both thoroughly and quantitatively opens up possibilities for further quantitative studies. They told Dental Learning Hub about the study.
Question: Give some background on why OCT was used in your study to image the site of fracture initiation?
Braz and Gomes: As already widely recognized, OCT is a spectacular technique for non-invasive and non-destructive imaging, particularly if one is working with minute dimensions and require micronmeter resolution. We realized that most tests on dental materials are destructive. OCT can ‘see inside’ composite materials and we can then evaluate what is going on. In the particular case of fracture, it works really well and is opening up great possibilities.
Question: What are the most significant outcomes of your study?
Braz and Gomes: The fact that we can follow crack initiation, quantify it, and most importantly, do it in real time (while the fracture process is being tested) is significant. Also, as an important aggregate value, the imaging is almost instantaneous (milliseconds). As this is the first demonstration of this, we are very pleased with the outcome.
Question: How does your study contribute to the current evidence base on cracks in composites?
Braz and Gomes: It clearly shows the features expected from theory, and reproduces results already known from fractography, which employs others methods which are, however, destructive and time-consuming. Furthermore, I always like saying that, in many cases, new methods are not just to substitute others, but to add and facilitate our comprehension of basic science and its implications.
Question: Will you conduct further research in this area?
Braz and Gomes: Definitely yes. We are performing a series of measurements in other composite materials, and are also setting up a system to evaluate crack propagation in situ. Furthermore, we are identifying collaborators to develop theoretical work, so one can have complete understanding of crack propagation in dentistry.
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Full article
“Evaluation of crack propagation in dental composites by optical coherence tomography” Dental Materials
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Research conducted at Universidade Federal de Pernambuco in Recife, Brazil analysed the images sites of fracture initiation and slow crack propagation in a fiber reinforced composite using optical coherence tomography (OCT). Drs Ana Braz and Anderson Gomes from the university’s Graduate Programme in Odontology, concluded that OCT images provide a superior insight into crack propagation, which cannot be seen by the naked eye. By using OCT the possibility of analyzing fracture propagation both thoroughly and quantitatively opens up possibilities for further quantitative studies. They told Dental Learning Hub about the study.
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