Assessing the physical and mechanical properties of 3D printed acrylic material for denture base application

• Published in: Dental materials Vol. 38; no. 12; pp. 1841 - 1854
• Main Authors: Altarazi, Ahmed, Haider, Julfikar, Alhotan, Abdulaziz, Silikas, Nick, Devlin, Hugh
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01-12-2022; Elsevier BV
• Subjects: 3D-printing; Conversion; Cost effectiveness; Curing; Dental materials; Dental Materials - chemistry; Dentists; Denture base; Denture Bases; Dentures; Diamond pyramid hardness tests; Fabrication; Flexural strength; Fourier transforms; Hardness; Humans; Materials Testing; Mechanical properties; Modulus of rupture in bending; Physical properties; PMMA; Polymer resin; Polymethyl Methacrylate - chemistry; Printing; Printing, Three-Dimensional; Professional Role; Prostheses; Resins; Saliva; Sorption; Stereolithography; Surface Properties; Three dimensional printing; Stereolithography; PMMA; Denture base; 3D-printing; Polymer resin
• ISSN: 0109-5641; 1879-0097
• DOI: 10.1016/j.dental.2022.09.006

Three-dimensional (3D) printing is increasingly being utilised in the dental field because of its time-saving potential and cost effectiveness. It enables dental practitioners to eliminate several fabrication steps, achieve higher precision, and attain consistency in complex prosthetic models. The properties of 3D-printed resin materials can be affected by many factors, including the printing orientation (PO) and insufficient post-curing time (CT). This study aimed to investigate the effect of PO and CT on the mechanical and physical properties of a 3D-printed denture base resin (NextDent).
3D-printed specimens were fabricated in 0°, 45°, and 90° POs, followed by three CTs (20, 30, and 50 min). The microhardness was tested using a Vickers hardness test, while the flexural property was evaluated using a three-point bending test. Sorption and solubility were measured after the specimens had been stored in an artificial saliva for 42 days, and the degree of conversion during polymerisation was analysed using Fourier Transform Infra-red (FTIR) spectroscopy.
The flexural strength of the material significantly increased (p < 0.05) when the printing orientation was changed from 0° to 90°. A similar increase was observed in the hardness, degree of conversion, and water sorption results. In general, no significant difference (p > 0.05) in any of the tested properties was found when the post-curing times were increased from 20 to 50 min.
The highest physical and mechanical properties of the 3D-printed denture base resin can be obtained by printing vertically (90° angle to the platform base). The minimal post-curing time to achieve ideal results is 30 min, as further curing will have no significant effect on the properties of the material.
[Display omitted]
•The effect printing orientations and post curing times on 3D printed PMMA resin is studied.•90° orientation can provide higher mechanical and physical properties.•Post curing time greater than 30 min does not have any significant effect on material properties.•Microscopic images did not show any layer separation within the material itself.