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Updated: Jun 24, 2026

Impact of Fabrication Techniques and Polishing Procedures on Surface Roughness of Denture Base Resins
Published on: January 17, 2025
Surface roughness and color stainability of conventional, subtractive, and additive denture base materials after
Selin Tarak1, Göknil Ergün Kunt2, Rafat Sasany3
1Research Assistant, Department of Prosthodontics, Faculty of Dentistry, University of Ondokuz Mayis, Samsun, Turkey.
Statement Of Problem:
Thermal aging, brushing, and staining may compromise the surface and optical behavior of denture base materials. Evidence is limited regarding the combined effects of these conditions on conventionally processed, subtractively manufactured (SM), and additively manufactured (AM) resins.
Purpose:
The purpose of this in vitro study was to compare the surface roughness (Ra) and color stainability (ΔE00) of denture base resins fabricated using conventional, SM, and AM methods after brushing and immersion in staining media.
Material And Methods:
A total of 180 disk-shaped specimens were fabricated using conventional heat-polymerized polymethyl methacrylate (PMMA) (C), SM prepolymerized PMMA (SM), and AM photopolymerizable PMMA-based resin (AM) (n=60 per group). Baseline Ra and color were recorded. After thermocycling, each group was divided into brushing (WB) and nonbrushing (NB) subgroups (n=30 each), followed by immersion in distilled water, coffee, or red wine (n=10 each). Final Ra and color were reassessed, and ΔE00 was calculated. Surface topography was examined using scanning electron microscopy. Ra was analyzed using 2-way ANOVA (fabrication × brushing). ΔE00 was evaluated using a factorial ANOVA with fabrication method, solution, and brushing as fixed factors (α=.05).
Results:
Fabrication method and brushing significantly influenced Ra (P<.001). AM showed the highest Ra, C intermediate values, and SM the lowest, both before and after brushing. For ΔE00, significant main effects of fabrication method, solution, and brushing were observed, and a fabrication×solution interaction was detected (P<.001). The greatest ΔE00 occurred in AM-WB immersed in wine, whereas the lowest values occurred in SM-NB immersed in distilled water. WB-NB differences were significant in coffee for all materials, nonsignificant in wine, and significant in distilled water only for conventional specimens.
Conclusions:
Subtractive PMMA demonstrated superior resistance to surface degradation and discoloration, whereas additively manufactured denture base resins were more susceptible to these changes, indicating that dentures fabricated by additive manufacturing may require closer clinical follow-up and maintenance.
