Chromatic Stability of Three Photopolymerizable Resins for Additive Manufacturing Following Immersion in Artificial Saliva: A Comparative Spectrophotometric Analysis

Objective: This study compared the color stability of three photopolymerizable resins (Anycubic Bio Resin White, V-Print c&b temp, GC Temp Print) after immersion in artificial saliva at 37 °C. Materials and Methods: Thirty-six disc specimens (10 mm × 1.5 mm) were printed on a Planmeca Creo C5 LCD printer and divided into control (T0), 24 h (T24), and 72 h (T72) groups (n = 4). CIELAB coordinates were measured spectrophotometrically, and ΔE was calculated using the CIE76 formula. Results: Material was the dominant factor for all color parameters (η2p = 0.774–0.964, all p < 0.001), while immersion time was not significant (all p > 0.05). Mean ΔE at T24/T72 was 0.90/0.66 (Anycubic), 2.25/3.79 (VOCO), and 4.48/3.58 (GC). The Kruskal–Wallis test detected an overall difference among materials at T72 (H(2) = 7.423, p = 0.024); however, no pairwise comparison remained significant after Bonferroni correction. At T24, one of four Anycubic specimens exceeded the perceptibility threshold (ΔE = 1.2), whereas 75% of GC Temp Print specimens exceeded the clinical acceptability threshold (ΔE > 3.7). Conclusions: Material composition was the primary determinant of chromatic behavior; resin selection remains critical for the aesthetic performance of 3D-printed provisional restorations.