A Novel Resin System for Dental Applications and Its Properties

Objectives: The objective of this study was to develop and evaluate a novel resin system for provisional dental applications. Methods: The flexural strength and modulus specimens (2mm x 2mm x 25mm) of experimental resins were typically polymerized for 6-minutes in a Triad 2000 light unit sold by Dentsply International Inc. and tested according to ISO10477. Compressive cylinder specimens of experimental resins (4mm in diameter X 8mm height) were also polymerized in Triad 2000 light unit. The commercial available provisional materials were prepared according to the manufacturers' instructions. The flexural properties were determined using three-point flexure test at an Instron crosshead speed of 0.75mm per minute. The wear resistance was measured by using a three-body abrasion wear machine (Leinfelder Method in vitro) to determine volume loss after 400,000-cycles at 50rpm. Compressive strength was measured at an Instron crosshead speed of 50.8mm per minute. Polymerization shrinkage was measured by Helium Pycnometer. Thermal analyses were carried out on a Perkin-Elmer Pyris 1 DSC. The mechanical properties of each formulation were statistically compared by ANOVA (a = 0.05). Results: A novel resin system was developed with low polymerization shrinkage (2.2% by volume for Resin 1). A part of polymerization shrinkage is offset from volume expansion during the phase transition of crystallized resin. The experimental resins had excellent flexural strength and modulus. They also showed superior compressive strength and wear resistance compared to the tested commercial materials.

Flexural Strength and Modulus of Various Materials

Conclusion: A novel resin system has been developed with excellent physical and mechanical properties, which is expected to be suitable for use in provisional dental applications.