The Influence of Various Photoinitiators on the Properties of Commercial Dental Composites

Andrea Kowalska; Jerzy Sokolowski; Tomasz Gozdek; Michał Krasowski; Karolina Kopacz; Kinga Bociong

doi:10.3390/polym13223972

The Influence of Various Photoinitiators on the Properties of Commercial Dental Composites

Polymers (Basel). 2021 Nov 17;13(22):3972. doi: 10.3390/polym13223972.

Authors

Andrea Kowalska¹, Jerzy Sokolowski¹, Tomasz Gozdek², Michał Krasowski³, Karolina Kopacz^{4

5}, Kinga Bociong¹

Affiliations

¹ Department of General Dentistry, Medical University of Lodz, 92-213 Lodz, Poland.
² Institute of Polymer & Dye Technology, Lodz University of Technology, Stefanowskiego 12/16, 90-924 Lodz, Poland.
³ University Laboratory of Materials Research, Medical University of Lodz, Pomorska 251, 92-213 Lodz, Poland.
⁴ "DynamoLab" Academic Laboratory of Movement and Human Physical Performance, Medical University of Lodz, Pomorska 251, 92-215 Lodz, Poland.
⁵ Department of Health Sciences, Medical University of Mazovia, Rydygiera 8, 01-793 Warszawa, Poland.

Abstract

The aim of this article was to compare the biomechanical properties of commercial composites containing different photoinitiators: Filtek Ultimate (3M ESPE) containing camphorquinone (CQ); Estelite Σ Quick (Tokuyama Dental) with CQ in RAP Technology^®; Tetric EvoCeram Bleach BLXL (Ivoclar Vivadent AG) with CQ and Lucirin TPO; and Tetric Evoceram Powerfill IVB (Ivoclar Vivadent AG) with CQ and Ivocerin TPO. All samples were cured with a polywave Valo Lamp (Ultradent Products Inc.) with 1450 mW/cm². The microhardness, hardness by Vicker's method, diametral tensile strength, flexural strength and contraction stress with photoelastic analysis were tested. The highest hardness and microhardness were observed for Filtek Ultimate (93.82 ± 17.44 HV), but other composites also displayed sufficient values (from 52 ± 3.92 to 58,82 ± 7.33 HV). Filtek Ultimate not only demonstrated the highest DTS (48.03 ± 5.97 MPa) and FS (87.32 ± 19.03 MPa) but also the highest contraction stress (13.7 ± 0.4 MPa) during polymerization. The TetricEvoCeram Powerfill has optimal microhardness (54.27 ± 4.1 HV), DTS (32.5 ± 5.29 MPa) and FS (79.3 ± 14.37 MPa) and the lowest contraction stress (7.4 ± 1 MPa) during photopolymerization. To summarize, Filtek Ultimate demonstrated the highest microhardness, FS and DTS values; however, composites with additional photoinitiators such as Lucirin TPO and Ivocerin have the lowest polymerization shrinkage. These composites also have higher FS and DTS and microhardness than material containing CQ in Rap Technology.

Keywords: Ivocerin; Lucirin TPO; RAP technology®; camphorquinone; commercial composite; dental composites; preventive dentistry; resin-based composite; restorative dentistry.