Background Polymethylmethacrylate (PMMA) is the most often used polymer for denture bases because to its inexpensive cost, lightweight nature, insolubility in mouth fluid, outstanding cosmetic features, and ease of repairability. However, various limitations such as insufficient surface hardness, low strength, brittleness, weak flexural strength, poor impact strength, and low fatigue resistance have a detrimental impact on acrylic resins. Method This research examined the impact strength, transverse strength, surface hardness, surface roughness, and color stability of heat-cured acrylic denture base material after 0.5% and 1% by wt. CNFs were added. The cellulose nanofibers were combined with a PMMA monomer for 5 minutes in a probe sonicator. One group of samples was made without cellulose nanofibers in PMMA, while two groups were prepared with 0.5% and 1% CNFs by weight, and tests of the impact strength, transverse strength, surface hardness, surface roughness, and color stability of the samples were carried out. The data were analyzed using descriptive statistics, including the mean and standard deviation, and bar charts were used to visualize the results. Sample interactions and fiber dispersion were assessed using FTIR and FE-SEM. Results Compared to the control group, 0.5% by wt. and 1% by wt. CNF improved the impact and transverse strength substantially, while shore D surface hardness was not improved. Hue (a) and chroma (b) were substantially influenced by CNF at 0.5% by weight compared to the control group, although surface roughness and color value (L) were not. Surface roughness, color value (L), and color hue (a) were substantially impacted by 1% compared to the control group; however, color chroma (b) was not. Conclusions This research found that 0.5% and 1% by wt. CNF in PMMA resin increased the impact strength, transverse strength, surface hardness, surface roughness, color value, hue, and chroma of heat-cured polymethyl methacrylate denture base material.
