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Two Dimensional Gradient Platforms for Rapid Assessment of Dental Polymers: A Chemical, Mechanical and Biological Evaluation



Nancy Lin, Peter Drzal, Sheng Lin-Gibson


Objectives: The increased usage of composite dental restorations underscores the need for continued improvements in material properties. Well-controlled sample fabrication and reproducible methods to quantify and compare material properties will accelerate material design and optimization. Our objectives were to fabricate samples encompassing a range of processing parameters and develop techniques that systematically quantify multiple properties on these samples, thus reducing sample-to-sample variation while concurrently testing numerous processing conditions. Methods: Gradient samples were prepared to evaluate the effects of composition and irradiation time. Comonomers bisphenol-A dimethacrylate (BisGMA) and triethylene glycol dimethacrylate (TEGDMA) were varied discretely from 20:80 to 80:20 (mass ratio), and irradiation time was varied continuously across each composition. Conversion was measured using infrared spectroscopy, mechanical properties were evaluated using nanoindentation, and cell viability and density were quantified using fluorescence microscopy. Results: Higher BisGMA content increased the elastic modulus while higher TEGDMA content increased the conversion. Cell response depended only on irradiation time and not composition, with conversions of 52 % and 60 % required for normal viability and cell density, respectively. A single composition-irradiation combination to achieve all of the best properties (highest conversion, highest elastic modulus, lack of cytotoxicity) was not identified, illustrating the necessity of testing all combinations for several relevant properties. Significance: Simultaneously screening composition and conversion increased the experimental throughput and allowed for the quantification of chemical, mechanical, and biological properties in a controlled, reproducible fashion. This 2D gradient approach is useful for optimizing compositions and processing parameters to achieve the desired combination of properties.
Dental Materials


combinatorial, cytotoxicity, degree of conversion, dental restorative materials, FTIR-RM, mechanical properties, NIR, nanoindentation, viability


Lin, N. , Drzal, P. and Lin-Gibson, S. (2006), Two Dimensional Gradient Platforms for Rapid Assessment of Dental Polymers: A Chemical, Mechanical and Biological Evaluation, Dental Materials, [online], (Accessed April 16, 2024)
Created November 13, 2006, Updated October 12, 2021