Time dependent effects of various staining agents on colour of artificial teeth

Abstract

The purpose of this in vitro study was to evaluate the colour changes in six brands of porcelain and of acrylic teeth after their immersion in tea, filtered coffee and cola for 1 day, 1 week, 2 weeks and 4 weeks. The study comprised three brands of porcelain and three brands of acrylic teeth. Five central maxillary incisors from the six types of artificial denture teeth were distributed equally into four groups (n530) according to the four immersion solutions. Colour measurements on each tooth were made before their immersion, and repeated after 1 day, 1 week, 2 week and 4 week immersions in the four solutions using the CIE L*a*b* colour measuring system. The colourimetric data were converted to National Bureau of Standards units. The data were analysed statistically by repeated measures analysis of variance (ANOVA), one-and two-way ANOVA, and Tukey honestly significant difference (HSD) multiple comparison tests. It was found that tea was more chromogenic than either filtered coffee or cola, and that acrylic teeth that had been immersed in tea for 4 weeks displayed the greatest colour change when compared to porcelain teeth. Tea is more chromogenic than filtered coffee and cola. The colour stability of porcelain teeth is greater than that of acrylic teeth. The degree of discolouration of acrylic and porcelain teeth after their immersion in tea, filtered coffee and cola is time dependent.

Optical Properties and Color Stability of Denture Teeth—A Systematic Review

“…Nanocomposite (NC) denture teeth were investigated in 4 papers, 21,23,26,32 while 1 study 33 looked at composite resin teeth. Porcelain teeth were studied in 4 papers 11,31,34,35 . CAD/CAM and 3D printed denture teeth materials have gained popularity recently and were investigated in 3 studies out of 5 published in 2020 2,16,17 .…”

“…Certain conversions of systems were adopted by authors to yield clinical significance from the ΔE * values obtained. The obtained ΔE * values can be quantified by National Bureau of Standards (NBS) units to match the color differences under clinical conditions, as adopted in eight studies 8,9,11,22,31,35,39,41 . Scale defining thresholds for changes in color, namely the acceptability threshold and perceptibility threshold, were mentioned in 23 studies 2,10,12–14,16,17,21–32,34,35,41,44 …”

“…Porcelain teeth were identified to experience less color change after immersion in solutions compared to PMMA teeth 11,31,35 . Among various brands of PMMA teeth, Vita Physiodens (PMMA with microfillers) have the least staining potential after immersion in solutions; 29,38 while Biotone interpenetrating polymer network (IPN) teeth (PMMA with highly cross‐linked copolymers) have the most color change as shown in different studies 12,27,30 …”

“…Twelve studies did not specify shade of denture teeth used for their experiment 7,22,24,27,30–32,35,37–40 . However, it is critical to report the selected tooth shade for readers to be able to make a comparison with other studies.…”

“…The degree of staining is proportional to the period of immersion in most studies 7,27,35,41 . However, Barzyk et al found that there is more staining in the initial period of immersion 58 .…”