This paper reviews acrylic denture base resin enhancement during the past few decades. Specific attention is given to the effect of fiber, filler, and nanofiller addition on poly(methyl methacrylate) (PMMA) properties. The review is based on scientific reviews, papers, and abstracts, as well as studies concerning the effect of additives, fibers, fillers, and reinforcement materials on PMMA, published between 1974 and 2016. Many studies have reported improvement of PMMA denture base material with the addition of fillers, fibers, nanofiller, and hybrid reinforcement. However, most of the studies were limited to in vitro investigations without bioactivity and clinical implications. Considering the findings of the review, there is no ideal denture base material, but the properties of PMMA could be improved with some modifications, especially with silanized nanoparticle addition and a hybrid reinforcement system.

Denture stomatitis (DS) is a multifactorial disease, but the proliferation of Candida albicans (C. albicans) is the main causative factor. Different modalities have been suggested for the prevention and treatment of DS. Among the different approaches that have been implemented to inhibit and control DS there are the topical application of antifungal agents, the surface modification of the denture base and the incorporation of antimicrobial agents into the denture base material. Antifungal agents can effectively control DS, but the recurrence of the disease is common. Accordingly, it has been suggested that coating the surface of the acrylic denture base may result in a decreased fungal adhesion. In recent years, nanotechnology has dominated the research, and several nanoparticles have demonstrated antifungal effects. Therefore, the aim of this article was to review the antifungal effects of the different methods that have been suggested for the prevention and/or control of DS as well as the antimicrobial activity of denture base acrylic resin additives, including nanoparticles. Studies reporting the incorporation of antifungal/antimicrobial agents into the polymethyl methacrylate (PMMA) denture base were included in this review. The PubMed, Web of Science, Google Scholar, and Scopus databases were searched for the articles published between January 2000 and December 2018 using the following key words: dental prosthesis, denture stomatitis, candidiasis, antifungal agents, biofilm formation, polymethyl methacrylate, and PMMA. The antimicrobial material incorporated into the resin may have a superior effect in preventing DS over simply coating the surface of the denture base. However, some antimicrobial fillers can have adverse effects on the physical and mechanical properties of the denture base resin.

This study assessed the influence of CAD/CAM milling and 3D-printing fabrication methods on mechanical properties of 3-unit interim fixed dental prosthesis (IFDPs) after thermo-mechanical aging. Forty 3-unit IFDPs were fabricated on a mandibular right second premolar and second molar of a typodont cast. Samples were fabricated from the following materials; auto-polymerized polymethyl methacrylate (conventional resin), CAD/CAM PMMA (milled resin) and two different CAD/CAM 3D-printed composite resins; digital light processing Asiga (DLP AS) and stereolithography NextDent (SLA ND). Mechanical properties were compared between the studied materials using Kruskal–Wallis test, followed by multiple pairwise comparisons using Bonferroni adjusted significance. There was a significant difference in flexural strength and microhardness between the studied materials (p < 0.001), with the highest mean ± SD reported in the milled IFDPs (174.42 ± 3.39, 27.13 ± 0.52), and the lowest in the conventional IFDPs (98.02 ± 6.1, 15.77 ± 0.32). Flexural strengths differed significantly between the conventional IFDPs and all materials except DLP AS. The highest elastic modulus was recorded in the milled group, and the lowest in the SLA ND group (p = 0.02). In conclusion, superior flexural strength, elastic modulus, and hardness were reported for milled IFDPs. SLA ND printed IFDPs showed comparable mechanical properties to milled ones except for the elastic modulus.