Does Energy Drinks Affect Color and Roughness of CAD/CAM Materials?

Objectives: The purpose of this in vitro study was to evaluate the effect of energy drinks on color stability (ΔE) and surface roughness (Ra; µm) of CAD/CAM materials; a resin infused hybrid ceramic, Vita Enamic (ENA; Vita Zahnfabrik), a nano-particle and nano-cluster-filled resin, Lava Ultimate Restorative (LVU; 3M ESPE), and a nano-particle-filled resin, Cerasmart (CES; GC) and a nanohybrid composite Essentia (ES; GC) used as a control over a two month period.
Methods: 32 CAD/CAM blocks were cut into 12x14x16mm specimens (n:60 from each type of material), and finished with 320-grit and then polished with 600-800-1200-grit SIC papers in order to simulate intra-oral finishing and polishing. A total of 60 composite specimens were prepared using a metal mold in 2mm thickness and 10 mm in diameter and polymerized using a LED curing unit (Demi Ultra; Kerr), stored in distilled water at 37 ^oC for 24 hours. Initial ΔE of the specimens (n:30 from each type of material) were evaluated with a spectrophotometer (Minolta CM-2600d) while initial surface roughness (n:30 from each type of material) with a profilometer (Perthometer, Mahr). Then the specimens in each group were randomly divided into three subgroups according to one of the energy drinks Burn (BR; n:10), Redbull (RB; n:10) and control (n:10). Control group specimens (C) were aged in distilled water while experimental group specimens were immersed in energy drinks for 2 minutes daily and ΔE and Ra evaluations were performed after 1 and 2 months aging. ΔE and Ra data were analyzed by three-way ANOVA and post-hoc Bonferroni tests (p<0.05).
Results: All the tested materials showed significant color change in distilled water and energy drinks after one and two months aging (p<0.05). However there were no significant differences between BR, RB and C in each material group at both evaluation periods (p>0.05). Significant Ra increase was observed in all materials after two months aging (p<0.05) and BR and RB resulted in higher increase than C (p<0.05).
Conclusions: Energy drinks did not affect the color of CAD/CAM materials and direct composite however increased the surface roughness of the materials after short term evaluation.