Using the Canadian Light Source (CLS) at the University of Saskatchewan, an international team of researchers have reported that it has closed a gap in the knowledge of photoactivated resin-based composites commonly used in medical and dental applications such as fillings.
The researchers said that they have seen inside the resin matrix and gained insight into how filler particles interact with it during setting as well as how these filler particles influence dental filling materials.
“We’ve been working for a number of years using synchrotron-based techniques primarily to try and understand the evolving structure of the polymer network of the resin matrix that makes up these materials,” said Owen Addison, BDS, PhD, leader of the study and chair of oral rehabilitation at the King’s College London Faculty of Dentistry, Oral & Craniofacial Sciences and adjunct professor of dentistry at the University of Alberta.
The researchers used a synchrotron technique that allows them to look at different resin chemistries and filler compositions. This will help researchers optimize the material, make it more resistant to wear and mechanical deterioration, and lead to less time spent in the dental office, they said.
The technique, wide field mid-infrared imaging, was used at the Mid-IR beamline at the CLS and allowed the team to gain a greater understanding of what was happening with the matrix of the resin composite, which is used for dental work.
The filler particles are introduced to the material for better mechanical performance, but there has been a significant gap in the knowledge about the way these fillers affect the polymerization, or hardening, of the material, the researchers said.
For the first time, the researchers said, they were able to demonstrate that the fillers themselves modify the local reaction of the setting material. Addison believes this information could lead to better resin composites in dental and medical applications as well as in industrial applications like windshields for the automotive industry.
The study, “Origin of Micro-Scale Heterogeneity in Polymerisation of Photo-Activated Resin Composites,” was published by Nature Communications.