Abstract
This study aimed to evaluate the colour stability of polymethyl methacrylate (PMMA) denture base reinforced with ZrO
nanoparticles, E-glass fibres, and TiO
nanoparticles at various concentrations over 180-day storage in Steradent™ (STD) denture cleaner or coffee (CF). A total of 130 disc-shaped specimens were fabricated at various filler concentrations and divided into four main groups to measure the colour changes. Groups Z, T, and E consisted of PMMA reinforced with ZrO
nanoparticles, TiO
nanoparticles, or E-glass fibre, respectively, while Group C consisted of PMMA specimens without filler served as the control group (
= 10). The three reinforced groups were further subdivided according to the filler content (
= 10) added to the PMMA (1.5%, 3.0%, 5.0%, and 7.0% wt.%). Half of the specimens were stored in STD, while the other half was stored in CF for 180 days. A Minolta Chroma Meter was used to measure the colour changes (ΔE) at 7, 30, 90 and then 180 days. The results were assessed using two-way repeated-measures analysis of variance (RM-ANOVA) along with Bonferroni post hoc tests at a
≤ 0.05 significance level. Significant different colour changes (ΔΕ) were observed between all tested groups and across different time points. TiO
-reinforced PMMA in STD/CF showed the lowest colour stability, while the E-glass fibre-reinforced PMMA in STD/CF showed the highest colour stability. Furthermore, coffee appeared to have the greatest impact on the colour change in comparison to the Steradent
. The results indicated that the filler type and concentration, type of solution, and length of storage all affected the colour stability of the tested specimens.