Properties of a Bulk-Fill Flowable Composite Resin with High Depth of Cure

Abstract

Introduction: Dental composite resin materials are being increasingly used for a variety of purposes and more recently as a dentine replacement material. Objectives: SDR (Dentsply) is a flowable, high-resin composite material designed to minimise the effect of the high shrinkage through the use of a flexible monomer. However the resultant properties of this material may be a factor that affects the clinical performance. Methods: Tests were carried out on SDR and two other commonly used resin-based composite materials (Herculite XRV, Kerr and Spectrum TPH, Dentsply) including: depth of cure according to ISO 4049, degree of cure using Fourier Transform Infrared Spectroscopy (FTIR), compressive strength using a Universal testing Machine, water uptake, interaction with Coca-ColaTM and analysis of thermal transitions using Differential Scanning Calorimetry (DSC). Results: SDR exhibited a high depth of cure at 4.0 mm and no difference in degree of cure in comparison with the other two dental composites. Compressive strength results varied between materials but were significantly lower for SDR (P < 0.05). Water uptake was similar for all materials but elution was significantly greater for SDR and interaction with Coca-Cola showed greatest change for SDR. Conclusions: There are some statistically significant variations between the physical properties of the materials which are attributed to the monomer type and lower amount of filler in the flowable composite that may explain the published clinical outcomes.