Effect of Washing Condition on the Fracture Strength, and the Degree of Conversion of 3D Printing Resin

• Published in: Applied sciences Vol. 11; no. 24; p. 11676
• Main Authors: Jang, Woohyung, Kook, Gyeong-Soo, Kang, Jin-Ho, Kim, Yeseul, Yun, Yina, Lee, Seon-Ki, Park, Sang-Won, Lim, Hyun-Pil, Yun, Kwi-Dug, Park, Chan
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.12.2021
• Subjects: 3-D printers; 3D printing; Accuracy; Contact angle; Conversion; degree of conversion; Dental materials; Flexural strength; Fracture strength; IPA; Mechanical properties; Resins; Statistical analysis; Surface energy; Surface properties; Surface roughness; TPM; Variance analysis; Washing; washing time; United States > US
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app112411676

This study compared the surface roughness, contact angle, surface energy, residual monomers, degree of conversion, and flexural strength of 3D-printed dental resin under various washing conditions. The specimens were printed with a digital light processing (DLP) printer and were divided into four groups: the group dipped in IPA for 5 s (IPA-D), the group washed in IPA for 1 min (IPA-1), the group washed in IPA for 10 min (IPA-10), and the group washed with TPM for 10 min (TPM-10). Following, the groups were redivided into two groups: a cured group and an uncured group. All experimental data were statistically analyzed using one-way analysis of variance and Tukey’s test. In all groups, the surface roughness showed a value of 1.2–1.8 μm, with no significant difference (p > 0.05). Contact angle showed a significant difference between the three groups using IPA and the TPM group, whereby the TPM-washed specimen showed a low contact angle (p < 0.05). The degree of conversion (DOC) increased in the following order: IPA-D group, IPA-1 group, IPA-10 group, and TPM-10 group, exhibiting a significant difference between all groups (p < 0.05). Flexural strength was measured at 110–130 MPa in all groups, with no significant difference between groups (p > 0.05). The washing time and washing solution type of the 3D printing material had no significant effect on surface roughness and flexural strength.