Stainability and translucency of potassium aluminum sulfate applied <scp>computer‐aided design and computer‐aided manufacturing</scp> materials after coffee thermocycling
Rafat Sasany, Mustafa Borga Dönmez, Marcella Silva de Paula, Çiğdem Kahveci, Gözlem Ceylan, Burak Yılmaz, Gülce Çakmak
Abstract
Abstract 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 (Δ E 00 ) 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 Δ E 00 after alum application ( p ≤ 0.006), except for FC ( p = 0.177). In addition, alum applied RCR had lower Δ E 00 values than its control specimens ( p = 0.029). Alum applied specimens had their lowest RTP after CTC ( p < 0.001) and alum application decreased the RTP of CT ( p = 0.010). CTC reduced the RTP of all materials in control groups ( p < 0.001). Alum applied CT had higher RTP than its control specimens ( p = 0.049). Conclusions Alum application's effect on color change varied depending on the material and alum mostly resulted in clinically acceptable changes in translucency. CTC led to unacceptable color and translucency changes based on previously reported threshold values. Clinical Significance Optical properties of CAD‐CAM materials and the sustainability of these properties over time is critical for longevity. Alum may improve the color stability of reinforced composite resin when subjected to long‐term coffee consumption.