A Comparative Study of the Mechanical Properties of Selected Dental Composites with a Dual-Curing System with Light-Curing Composites

<strong>Abstract: </strong>Dual-curing composites have a wide spectrum of use in practice (rebuilding, reconstruction, and luting). The characterization of this type of material and comparative study of selected mechanical properties with light-cured materials were carried out for this paper. In this study, we used six materials with a dual-cure system—Bulk EZ, Fill-Up!, StarFill 2B, Rebilda DC, MultiCore Flow, Activa Bioactive-Restorative—and three light-cured materials—Filtek Bulk Fill Posterior, Charisma Classic, and G-aenial Universal Flo. The materials were conditioned for 24 h in water at 37 °C before testing. Selected material properties were determined: three-point bending flexural strength, diametral tensile strength, hardness, microhardness, and shrinkage stress. The highest three-point bending flexural strength (TPB) was 137.0 MPa (G-aenial Universal Flo), while the lowest amounted to 86.5 MPa (Activa Bioactive). The diametral tensile strength (DTS) values were in a range from 39.2 MPa (Rebilda DC) to 54.1 MPa (Charisma Classic). The lowest hardness (HV) value of 26 was obtained by the Activa Bioactive material, while the highest values were recorded for Filtek Bulk Fill Posterior and Charisma Classic-53 . The shrinkage stress of the tested materials ranged from 6.3 MPa (Charisma Classic) to 13.2 MPa (G-aenial Universal Flo). Dual-curing composites were found to have similar properties to light-cured composites.摘要：双重固化复合材料（dual-curing composites）在临床实践中应用场景广泛，可用于修复、重建以及修复体粘接固位。本研究针对此类材料开展了性能表征，并选取光固化复合材料（light-cured materials）作为对照，对二者的部分力学性能展开对比研究。本研究共选用9种牙科修复材料，其中6种为双重固化体系材料：Bulk EZ、Fill-Up!、StarFill 2B、Rebilda DC、MultiCore Flow及Activa Bioactive-Restorative；剩余3种为光固化复合材料：Filtek Bulk Fill Posterior、Charisma Classic及G-aenial Universal Flo。所有受试材料均在37℃去离子水中浸泡24小时进行前处理，随后开展性能测试。本研究测定了以下材料性能：三点弯曲抗弯强度、径向拉伸强度、硬度、显微硬度以及聚合收缩应力。受试材料的三点弯曲抗弯强度（TPB）最高值为137.0 MPa，出自G-aenial Universal Flo；最低值为86.5 MPa，对应Activa Bioactive。径向拉伸强度（DTS）的取值范围为39.2 MPa（Rebilda DC）至54.1 MPa（Charisma Classic）。硬度（HV）最低值为26，同样来自Activa Bioactive；最高值为53，对应Filtek Bulk Fill Posterior与Charisma Classic。受试材料的聚合收缩应力范围为6.3 MPa（Charisma Classic）至13.2 MPa（G-aenial Universal Flo）。研究结果表明，双重固化复合材料的性能与光固化复合材料较为相近。