Date of Award
Summer 7-24-2025
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
Ayman Ahmed
Second Advisor
Daniela Masson-Meyers
Third Advisor
Michael Karczewski
Abstract
Aim: In prosthodontics, polymethyl methacrylate (PMMA) has been widely used. Their biocompatibility and potential genotoxicity remain a concern due to the residual monomer release. Computer-aided design and manufacturing (CAD/CAM) denture base materials have emerged and offered some improved mechanical and physical properties compared to the standard conventional heat-cured denture base material. However, their long-term biocompatibility remains unstudied. Therefore, this study evaluates the genotoxicity effects of conventional and CAD/CAM denture base materials on human gingival fibroblasts (HGFs). Methodology: Disk-shaped samples were fabricated of six denture base resins, including heat-cured PMMA, milled PMMA, and four 3D-printed resins. HGFs were exposed to the extracts of these materials after incubation in a cell culture medium for 1 and 7 days. Then, DNA double-strand breaks (DSBs) were quantified using the γ-H2AX assay. Statistical analysis compared DNA damage levels across groups. Results: All materials showed initial DNA damage at baseline exposure (1 day). However, after 7 days, significant differences emerged. The 3D-printed resins (Ivoclar Ivotion Base Print and Sprintray High Impact Denture Base) showed the highest reduction in DNA damage, while heat-cured PMMA showed the least improvement. The other 3D-printed and milled PMMA resins displayed intermediate recovery. Conclusion: None of the investigated materials has reached the γ-H2AX genotoxicity threshold. CAD/CAM fabricated denture bases showed superior biocompatibility in both time points, likely due to optimized polymerization and reduced leaching monomer.