Mechanical and Antimicrobial Properties of Nanocellulose-Reinforced Heat-Cured Versus the Conventional Heat-Cured Acrylic Resins: An In Vitro Study.

BACKGROUND

Edentulism, the loss of natural teeth, affects mastication, speech, and esthetics. Dentures, usually made of heat-cured acrylic resin, replace function and esthetics. Conventional heat-cured acrylic resin-polymethyl methacrylate (PMMA), used for dentures is susceptible to fracture and fungal colonization by Candida, which can cause denture stomatitis. This study was done to investigate reinforcing PMMA with nanocellulose and its effect on the flexural strength, impact strength and antimicrobial properties of PMMA.

MATERIALS AND

METHODS

A total of 90 heat-cured acrylic resin specimens were fabricated using DPI Heat Cure acrylic resin (The Bombay Burmah Trading Corporation Ltd., India) with nanocellulose particles (Vedayukt India Pvt. Ltd., Jharkhand, India), incorporated. The samples were divided into three groups: control (conventional PMMA), 2.5% nanocellulose-reinforced PMMA, and 5% nanocellulose-reinforced PMMA. The specimens were evaluated for flexural strength, impact strength, and antifungal activity against Candida albicans. Statistical analysis was performed using one-way ANOVA followed by Bonferroni post hoc test.

RESULTS

Flexural strength increased with nanocellulose concentration, but the change was not statistically significant (p = 0.095). In contrast, impact strength showed a significant, dose-dependent improvement (p  < 0.001), with the 5% group being substantially stronger than the 2.5% group and the control group. No antifungal activity was observed in any group.

CONCLUSIONS

Within the limitations of this in vitro study, nanocellulose reinforcement of PMMA produced a significant, concentration-dependent increase in impact strength, with a nonsignificant improvement in flexural strength. The findings suggest that 5% nanocellulose reinforcement may enhance denture impact resistance and reduce fracture risk. No antifungal activity against Candida albicans was observed.