The objective of the materials testing project is to guide the evolution, refinement and fabrication of developing resin composites throughout the stages of their development. The general hypotheses is that a low shrinkage nanofilled resin composite will have mechanical and physical properties superior to a commercially available resin composite. Thus, in this project, 6 specific aims are proposed each with an underlying subsidiary hypothesis. The transverse strength and fracture toughness of the nanofiller particles in 1:1 Bis-GMA/TEGMA will be used as the screening test for specific aim 1 - It is hypothesized in specific aim 1 that the use of nanofiller particles in the resin will impart a transverse strength and fracture toughness that is equal to or greater than 80% of that of a commercially available resin composite.
Specific aim 2 will screen the Bis-acrylate and -methacrylate terminated nematic liquid crystal monomers(NLCM)using the polymerization shrinkage test.
In specific aim 2, it is hypothesized that the NLCM will have polymerization shrinkage that is less than 80% of the shrinkage of a clinically successful, commercially available resin composite. NLCM and nanofiller particles showing sufficient promise will be blended into various formulations of resin composite; and microstructural analyses, and mechanical and physical properties (specific aims 3, 4, and 5) will be used to characterize them. It is hypothesized in specific arms 3-5 that the nanofiller particles will be homogeneously distributed and that selected mechanical and physical properties will be superior to a commercially available resin composite. formulations showing promise will be subjected to shear bond testing using a commercially available dentin bonding agent in specific aim 6 and after dentin treatment with OP1/TGF-beta1 in specific aim 7. It is hypothesized in specific aims 6 and 7 that the shear bond strength of a prototype resin composites using a commercially available dentin bonding agent and after OP-l/TGF-beta1 treatment will be superior to the bond strength using a commercially available resin composite. It is through comprehensive tests that the ultimate formulation of the model resin composites will be selected for eventual scale up and biocompatibility evaluation.
Showing the most recent 10 out of 17 publications
