The long-term goal of the award applicant is to establish a competitive, independently funded research program that develops robust materials to address healthcare challenges. This goal will be realized through the execution of an organized, thorough, and integrated career development plan, effective mentorship, and an engaging and innovative research project. The proposed research project will investigate phase separation in self-etch adhesive resins and explore the use of monomers capable of adaptable, dynamic hydrogen bonding to improve overall adhesive performance. The three aims of this project will address the hypothesis that phase separation during adhesive polymerization forms weakened domains of the hybrid layer, which must be reinforced to ensure robust adhesive performance. To this end, the first goal of the research project is to study phase separation in model self-etch adhesives and to ascertain the resulting composition and morphology of heterogeneous domains that result during polymerization. The second goal of the research project is to develop a series of methacrylate monomers decorated with two different hydrogen bonding groups (catechol, and ureido-4[1H]-pyrimidinone ? UPy) and ascertain their performance in adhesive resins and efficacy at rearranging in response to applied stresses. The career development proposed for Dr. Caroline Szczepanski includes training in relevant experimental protocols to assess the performance, biocompatibility, and stability of polymeric materials intended for oral care. Additionally, broad training in skills necessary for the management of an independent career and funded research laboratory (e.g. grantsmanship, lab management) will be addressed. These goals are complemented by the choice of mentors and the institutional environment which will all assist in providing the skills and guidance needed by the applicant to develop a successful research program and succeed as an independent investigator. The mentor team will consist of Prof. Ana Bedran-Russo (University of Illinois Chicago ? UIC), Prof. Christina Chan (Michigan State University - MSU) and Prof. Marco Bottino (University of Michigan). Profs. Bedran-Russo and Bottino will provide critical guidance and training in the analysis of material performance in simulated oral environments (e.g. micro-tensile bond testing), as well as the use of dentin specimens to assess adhesive efficacy. Since both Profs. Bedran-Russo and Bottino are affiliated with schools of dental medicine, they will also provide Dr. Szczepanski with opportunities to attend research seminars, meet fellow researchers, and network within this new field of research. Prof. Chan will provide mentorship particularly focused on grantsmanship as well as navigating the path towards reappointment and tenure at MSU. In addition to these mentors, Dr. Szczepanski?s career development plan includes seminars in the grantsmanship, responsible conduct of research, and mentorship will be pursued throughout the award period. Together, the proposed research and career development plan will build upon the applicant?s expertise in polymer science to situate themselves as a significant contributor to NIDCR and NIH relevant research.
Dental adhesives are employed to create a sturdy and long-lasting bond between dentin and composite restorations, through the formation of a robust hybrid layer comprised of a three-dimensional polymer network that interlocks with native bone tissue. To date, the performance of such adhesives is sub-optimal, as the majority of composite failures are observed at restoration margins. The fundamental goal of this project is to understand the phase structure and composition of heterogeneities that form during adhesive polymerization, and to reinforce weakened regions of the hybrid layer through the development and application of monomers capable of adaptable, dynamic bond rearrangement.