Stainability and translucency of potassium aluminum sulfate applied computer‐aided design and computer‐aided manufacturing materials after coffee thermocycling

Objective The purpose of this in vitro study was to evaluate the effect of potassium aluminum sulfate (alum) application on the stainability and translucency of computer‐aided design and computer‐aided manufacturing (CAD‐CAM) materials after coffee thermocycling (CTC). Materials and Methods Disk‐shaped specimens (Ø10 × 1 mm; N = 200) were fabricated by using additively (Crowntec [CT] and Varseo Smile Crown Plus [VS]) and subtractively manufactured (Brilliant Crios [RCR], CEREC Block [FC], and Vita Enamic [VE]) CAD‐CAM materials and polished. All specimens were randomly divided into two groups as alum applied and control (n = 10). All specimens were then subjected to CTC (10,000 cycles at 5–55°C) and color coordinates were measured at each time interval. Color differences (ΔE00) and relative translucency parameters (RTPs) were calculated and the data were statistically analyzed (a = 0.05). Results Among tested time intervals, alum applied specimens had their lowest ΔE00 after alum application (p ≤ 0.006), except for FC (p = 0.177). In addition, alum applied RCR had lower ΔE00 values than its control specimens (p = 0.029). Alum applied specimens had their lowest RTP after CTC (p