Influence of Provisional Cement Type and Film Thickness on Color Difference and Translucency of DLP-Printed Provisional Restorations

To evaluate the influence of different provisional cement types and cement film thicknesses on the color and translucency of three-dimensional (3D)-printed provisional restorations. Disk-shaped provisional specimens were fabricated using a digital light processing (DLP) 3D printing system. Three provisional cements, including polycarboxylate cement, zinc oxide non-eugenol cement (TempBond NE), and translucent resin-based cement (TempBond Clear), were applied at two cement film thicknesses (50 and 100 μm). Color difference (ΔE 00) and relative translucency parameter difference (ΔRTP00) were measured using a spectrophotometer before and after cementation. Data were analyzed using two-way analysis of variance (ANOVA), followed by Tukey's post-hoc tests (α = 0.05). ΔE 00 values of the 3D-printed specimens changed significantly depending on cement type and film thickness (p < 0.001). The lowest values (0.45 for 50 μm and 0.53 for 100 μm thickness) were observed for the translucent resin-based cement (TempBond Clear), whereas the highest values (2.06 for 50 μm and 3.93 for 100 μm thickness) were observed for the zinc oxide non-eugenol cement (TempBond NE). For ΔRTP00, cement type significantly influenced translucency alteration (p < 0.001), with translucent resin-based cement (TempBond Clear) exhibiting the minimal translucency changes (0.14 for 50 μm and 0.18 for 100 μm thickness) across both conditions. Cement type is the primary determinant of color and translucency stability in 3D-printed provisional restorations. Increased cement film thickness is associated with greater color deviation, particularly when using opaque materials like zinc oxide non-eugenol cement. Careful selection of provisional cement and control of cement film thickness are essential for achieving predictable esthetic outcomes in digitally fabricated provisional restorations.