In-vitro Comparative Evaluation for the Surface Properties and Impact Strength of CAD/CAM Milled, 3D Printed, and Polyamide Denture Base Resins

OBJECTIVE: There is a paucity of data regarding the effect of fabrication techniques and compositions of CAD/CAM milled, 3D-printed, and polyamide flexible denture base resin materials (DBRMs) on the surface roughness (SR), surface hardness (SH), and impact strength (IS). Therefore, this study aimed to evaluate the SR, SH, and IS of CAD/CAM milled, 3D-printed, and polyamide flexible DBRMs. MATERIALS AND METHODS: Ninety specimens were constructed from different DBRMs and divided into three groups (CAD/CAM, 3D-printed, and polyamide DBRMs; n = 30) with specific measurements: 15 × 10 × 2.5 mm for SR and H tests and 80 × 10 × 4 mm notched specimen for IS test. SR meter and Vickers micro SH tester were used to measure SR and SH, respectively, whereas the IS was evaluated using Charpy’s impact testing machine. Data were collected and statistically analyzed using one-way analysis of variance and post hoc Tukey’s tests (α=0.05). RESULTS: There were significant differences between the tested materials (P< 0.05). The CAD/CAM milled showed lowest SR when compared with 3D-printed resin and polyamide flexible resin (P< 0.05); however, there was a significant increase in SH of CAD/CAM milled and 3D-printed DBRMs when compared with polyamide materials (P< 0.05). There was a significant increase in IS of polyamide and CAD/CAM milled resins when compared with 3D-printed DBRMs (P < 0.05). CONCLUSION: CAD/CAM milled resins showed high IS and SH with lower SR.