IADR Abstract Archives
High Colour Stability of Pourable and Light-curable Acrylic Denture Bases
Objectives: Colour stability is an important aesthetic requirement for denture bases. It could be influenced by different conditions including aging intraorally and cleaning extraorally. Accordingly, any new denture base material should be evaluated for colour stability. Some new materials have recently been developed which facilitate denture production. They are Eclipse, a light-cured UDMA-based polymer, and Weropress, a cold-cured PMMA pourable type. We compared their colour stability through 6 months simulated aging with that of conventional PMMA-based materials to determine their ranking and to establish whether they are suitable to substitute for conventional materials in terms of aesthetics.
Methods: Ten disc specimens (diameter=20mm, thickness=4mm) were produced from materials in table (1). HC, Ws and Ec samples were made following manufacturer’s instructions. CC samples were mixed at 2:1 g/mL and cured at 3 bar for 15 min at room temperature (RT). After polishing (P400 grit, fine grain pumice, polishing compound) the samples were stored in distilled water at RT for 2 days, then at 37°C for 180 days. Dry specimens were evaluated for colour before storage and at 2nd, 7th, 30th, 90th and 180th day of storage using a spectrophotometer (Ci6x, x-rite, US). Colour change was calculated following ISO 20795-1:2013.
Results: The colour changes can be seen in table 1. Using two-way repeated measures ANOVA (Holm-Sidak post-hoc test), no significant differences were found between storage groups of Weropress (P>0.05), while for CC were significantly different from each other (P<0.05) with CC showing the highest discolouration, and Ws the lowest (P<0.001). HC is higher than Ec but they are not significantly different at 180 days.
Conclusions: Within the limitations of this study:
Ranking the materials from best to worst colour stability: Ws, Ec, Hc, and finally CC
Ws and Ec can be used as potential alternative denture base materials to HC in terms of colour stability.
Methods: Ten disc specimens (diameter=20mm, thickness=4mm) were produced from materials in table (1). HC, Ws and Ec samples were made following manufacturer’s instructions. CC samples were mixed at 2:1 g/mL and cured at 3 bar for 15 min at room temperature (RT). After polishing (P400 grit, fine grain pumice, polishing compound) the samples were stored in distilled water at RT for 2 days, then at 37°C for 180 days. Dry specimens were evaluated for colour before storage and at 2nd, 7th, 30th, 90th and 180th day of storage using a spectrophotometer (Ci6x, x-rite, US). Colour change was calculated following ISO 20795-1:2013.
Results: The colour changes can be seen in table 1. Using two-way repeated measures ANOVA (Holm-Sidak post-hoc test), no significant differences were found between storage groups of Weropress (P>0.05), while for CC were significantly different from each other (P<0.05) with CC showing the highest discolouration, and Ws the lowest (P<0.001). HC is higher than Ec but they are not significantly different at 180 days.
Conclusions: Within the limitations of this study:
Ranking the materials from best to worst colour stability: Ws, Ec, Hc, and finally CC
Ws and Ec can be used as potential alternative denture base materials to HC in terms of colour stability.