Optical and surface characteristics of additively manufactured resin composite following immersion in functional beverages: a layer thickness-based comparison.

This study aimed to evaluate the effects of an immune-enhancing vitamin C beverage and natural orange juice on the optical properties and surface roughness of an additively manufactured resin composite fabricated with different print layer thicknesses. Ninety disc-shaped specimens (12 × 2 mm) were printed from a resin composite (Bego VarseoSmile TriniQ) at 25-µm, 50-µm, and 100-µm layer thicknesses (n = 10 per subgroup) with a 90° build orientation. Initial relative translucency parameter (RTP), color (T0), and surface roughness (Ra) were measured. Specimens were then immersed for 72 h in either a vitamin C beverage (Mucovit C; pH 2.2-2.5), natural orange juice (pH 2.9-4.0), or distilled water. Post-immersion measurements (T1) were compared using two-way ANOVA, Tukey's HSD, one-way ANOVA, and paired t-tests (α = .05). At baseline, RTP was significantly higher for 25-µm compared to 100-µm specimens in the distilled water group (P = .006). After immersion, only the 25-µm group showed a significant RTP reduction (P = .024). Ra increased significantly in the 25-µm group after exposure to both acidic solutions (P < .05). Color change (ΔE₀₀) varied by thickness in orange juice (P = .037) and the vitamin C drink (P = .002), with 50-µm specimens showing the highest discoloration. No significant differences were found in distilled water or between beverage types (P > .05). Thinner print layers enhanced initial translucency, but were more prone to surface roughening and discoloration after acidic exposure, highlighting a trade-off in esthetic durability.