Mechanical Properties and Biocompatibility of Urethane Acrylate-Based 3D-Printed Denture Base Resin

Jy-Jiunn Tzeng; Tzu-Sen Yang; Wei-Fang Lee; Hsuan Chen; Hung-Ming Chang

doi:10.3390/polym13050822

Mechanical Properties and Biocompatibility of Urethane Acrylate-Based 3D-Printed Denture Base Resin

Polymers (Basel). 2021 Mar 8;13(5):822. doi: 10.3390/polym13050822.

Authors

Jy-Jiunn Tzeng¹, Tzu-Sen Yang², Wei-Fang Lee³, Hsuan Chen⁴, Hung-Ming Chang^{1

5}

Affiliations

¹ Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, Taipei City 110, Taiwan.
² Graduate Institute of Biomedical Optomechatronics, Taipei Medical University, No. 250, Wuxing St., Xinyi Dist., Taipei City 110, Taiwan.
³ School of Dental Technology, Taipei Medical University, No. 250, Wuxing St., Xinyi Dist., Taipei City 110, Taiwan.
⁴ National Yang Ming Chiao Tung University, No. 1001, University Road, Hsinchu 300, Taiwan.
⁵ Department of Anatomy and Cell Biology, Taipei Medical University, No. 250, Wuxing St., Xinyi Dist., Taipei City 110, Taiwan.

Abstract

In this study, five urethane acrylates (UAs), namely aliphatic urethane hexa-acrylate (87A), aromatic urethane hexa-acrylate (88A), aliphatic UA (588), aliphatic urethane triacrylate diluted in 15% HDD (594), and high-functional aliphatic UA (5812), were selected to formulate five UA-based photopolymer resins for digital light processing (DLP)-based 3D printing. Each UA (40 wt%) was added and blended homogenously with ethoxylated pentaerythritol tetraacrylate (40 wt%), isobornyl acrylate (12 wt%), diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (3 wt%), and a pink acrylic (5 wt%). Each UA-based resin specimen was designed using CAD software and fabricated using a DLP 3D printer to specific dimensions. Characteristics, mechanical properties, and cytotoxicity levels of these designed UA-based resins were investigated and compared with a commercial 3D printing denture base acrylic resin (BB base) control group at different UV exposure times. Shore hardness-measurement data and MTT assays were analyzed using a one-way analysis of variance with Bonferroni's post hoc test, whereas viscosity, maximum strength, and modulus were analyzed using the Kruskal-Wallis test (α = 0.05). UA-based photopolymer resins with tunable mechanical properties were successfully prepared by replacing the UA materials and the UV exposure times. After 15 min of UV exposure, the 5812 and 594 groups exhibited higher viscosities, whereas the 88A and 87A groups exhibited lower viscosities compared with the BB base group. Maximum flexural strength, flexural modulus, and Shore hardness values also revealed significant differences among materials (p < 0.001). Based on MTT assay results, the UA-based photopolymer resins were nontoxic. In the present study, mechanical properties of the designed photopolymer resins could be adjusted by changing the UA or UV exposure time, suggesting that aliphatic urethane acrylate has good potential for use in the design of printable resins for DLP-type 3D printing in dental applications.

Keywords: complete denture base; digital light processing; photopolymer resin; polyurethane acrylate.