Color and Translucency Stability of Conventional, Milled, and 3D-Printed Provisional Restorative Materials After...

To evaluate the color and translucency changes of conventional, milled, and 3D-printed provisional restorative materials (PRMs) after cigarette smoke exposure and brushing.

A total of 120 disc-shaped (Ø6 mm × 2 mm) specimens were fabricated from conventional (CN; TempSmart, GC), milled (ML; FusionCeram), and 3D-printed (PR; TempPRINT, GC) PRMs (n = 40 per material). Specimens were randomly divided into smoke-exposed (S) and control (C) groups (n = 20). After 20 days of exposure (20 cigarettes/day, 2-second puffs, 60-second intervals) or artificial saliva storage, specimens underwent brushing simulation (15 strokes/day) to form S-BR and C-BR subgroups. Color and translucency were measured at baseline (T0), post-exposure (T1), and post-brushing (T2) using a spectrophotometer. Color change (ΔE00), translucency change (ΔTP00), and translucency parameter (TP00) were calculated. Data were analyzed using two-way robust ANOVA (5% trimmed means) and Tukey post hoc test (α = 0.05).

ML exhibited significantly lower ΔE00 values than CN and PR after cigarette smoke exposure (P < .001). Brushing reduced discoloration in all smoking groups, especially for ML (P < .05). PR showed the highest ΔTP00 values across groups, differing significantly only from ML (P = .008). ML consistently demonstrated the highest TP00 values across all groups (P < .001), indicating superior translucency retention.

Cigarette smoke adversely affected the optical properties of PRMs, particularly in conventional and 3D-printed resins. Milled materials exhibited superior resistance to discoloration and translucency change. Although brushing did not completely reverse staining, it effectively reduced discoloration, particularly in milled materials.