Purpose: To evaluate the effect of polishing and denture cleansers on the surface roughness (Ra) of new-generation denture base materials that are additively, subtractively, and conventionally fabricated, while also assessing their color change after cleansing.
Material and methods: One hundred and fifty disk-shaped specimens (Ø10 × 2 mm) were prepared from five denture base materials (one subtractively manufactured nanographene-reinforced prepolymerized polymethylmethacrylate (PMMA) (SM-GC), one subtractively manufactured prepolymerized PMMA (SM-PM), two additively manufactured denture base resins (AM-DT and AM-ND), and one heat-polymerized PMMA (CV) (n = 30). The Raof the specimens was measured before and after conventional laboratory polishing, while color coordinates were measured after polishing. Specimens were then divided into three subgroups based on the denture cleanser: distilled water, 1% sodium hypochlorite (NaOCl), and effervescent tablet (n = 10). The Raand color coordinates were remeasured after nine cleansing cycles over a period of 20 days. The CIEDE2000 formula was used to calculate the color differences (ΔE00). Two-way analysis of variance (ANOVA) was used to analyze the Ravalues before (n = 30) and after (n = 10) cleansing, while repeated measures ANOVA was used to analyze the Raof material-time point pairs within each denture cleanser (n = 10). ΔE00data after denture cleansing was also analyzed by using two-way ANOVA (n = 10) (α = 0.05).
Results: Before polishing, Ravaried significantly among the materials. SM-GC and SM-PM had the lowest and AM-ND the highest Ravalues (P < 0.001). Polishing significantly reduced Raof all materials (P < 0.001), and after polishing, Radifferences among materials were nonsignificant (P ≥ 0.072). Regardless of the denture cleanser, the Raof AM-DT, AM-ND, and CV was the highest before polishing when different time points were considered (P < 0.001). After cleansing, AM-ND had the highest Raof all the materials, regardless of the cleanser (P ≤ 0.017). AM-DT had higher Rathan SM-PM when distilled water (P = 0.040) and higher Rathan SM-GC, SM-PM, and CV when NaOCl was used (P < 0.001). The type of cleanser significantly influenced the Raof AM-DT, AM-ND, and CV. For AM-DT, NaOCl led to the highest Raand the tablet led to the lowest Ra(P ≤ 0.042), while for AM-ND, distilled water led to the lowest Ra(P ≤ 0.024). For CV, the tablet led to lower Rathan distilled water (P = 0.009). Color change varied among the materials. When distilled water was used, SM-GC had higher ΔE00than SM-PM and AM-DT (P ≤ 0.034). When NaOCl was used, AM-ND had higher ΔE00than SM-GC, SM-PM, and AM-DT, while CV and SM-GC had higher ΔE00than SM-PM and AM-DT (P ≤ 0.039). Finally, when the tablet was used, AM-ND and CV had the highest ΔE00, while AM-DT had lower ΔE00than SM-GC (P ≤ 0.015).
Conclusions : readable in the article abstract or on Pubmed : https://pubmed.ncbi.nlm.nih.gov/37624691
