Physical Properties of a Filler-Containing Dental 3D Printing Resin Processed Using Printer Systems with Different Light-Source Wavelengths

This study compared the physical properties and color stability of specimens fabricated from a commercial filler-containing dental 3D printing resin using printer systems equipped with 405 or 385 nm light sources. Specimens were subjected to three-point flexural strength, Vickers hardness, water sorption, solubility, and color stability tests. Color stability was evaluated under dry (A), water-immersed (B), light-shielded (C), and light-exposed (D) conditions, and color differences (ΔE00) were calculated using the CIEDE2000 formula. Data were analyzed using Student’s t-test or Welch’s t-test, as appropriate (α = 0.05). Flexural strength and Vickers hardness were significantly higher, and solubility was significantly lower, in the 385 nm group than in the 405 nm group (p < 0.05), whereas water sorption did not differ significantly. The ΔE00 values were below the clinically acceptable threshold of 1.77 for all comparisons except A–B in the 405 nm group. The A–B and A–C values were significantly lower in the 385 nm group, whereas the B–C value was significantly higher (p < 0.05); no significant difference was observed for C–D. These findings suggest that differences between printer systems, including light-source wavelength, should be considered when fabricating dental prostheses using 3D printing resins.