| dc.description.abstract | Resin based cements (RBCs) have become very popular in dental practice for cementation of dental restorations, especially considering all-ceramics, due to improved adhesion features. However, one of the major concerns for the clinical performance of resin based cements is the polymerization shrinkage i.e. strainthat accompanies the chain-growth polymerization of dimethacrylate monomers. Also, RBCs can produce a considerable amount of heat, due to the light energy from the curing lights and exothermic reaction of polymerization.
The purpose of this study was to determine the temperature changes during the photo-polymerization using thermocouples and to measure strain field of the self-etching, self-adhesive RBC, Maxcem Elite (Kerr, Orange, CA, USA) using 3D optical system Aramis 2M (GOM, Braunschweig, Germany) based on Digital Image Correlation method. Three 05×2 mm sized and three 05×1 mm samples of Maxcem Elite were prepared by filling teflon ring-type moulds. Digital images were recorded immediately after photo-polymerization of the samples with a LED-curing unit for 20 s, according to manufacturer's recommendation. All measurements were performed at room temperature. Temperature curves indicated similar patterns. DIC showed that peripheral zone of the samples had the highest strain values in both groups. All the results were material-dependent and probably correlated to the composition of each material, which is not fully disclosed by the manufacturers. | sr |
