Discussion on Fatigue Strength of Dental PMMA

The fatigue strength of dental PMMA is influenced by multiple factors. The following is a discussion on its fatigue strength:

First, the influence of reinforcing materials on fatigue strength

Fiber reinforcement: Fiber-reinforced acrylic resin can enhance the fatigue strength of the resin. A number of studies have been carried out, using different types of fibers, such as nylon, polyethylene, polyamide fibers, especially glass fibers, because they have biocompatibility as well as excellent aesthetic and mechanical properties. Glass fiber reinforced materials have been found to significantly enhance the flexural strength, impact strength, toughness and Vickers hardness of acrylic resin, thereby improving fatigue strength.

Nanoparticle enhancement: Research on incorporating titanium dioxide nanoparticles into denture base resin has shown that this can improve the physical and mechanical properties of the material and may have a positive impact on fatigue strength.

Other reinforcing materials: Reinforcing PMMA with aluminum can enhance the flexural strength, impact strength, tensile strength, compressive strength and surface hardness of the resin. However, some studies have found that adding aluminum can reduce the impact strength and tensile strength of PMMA, which may be related to the stress concentration around the embedded metal and its poor adhesion to the polymer, thereby affecting the fatigue strength.

Second, the influence of processing technology on fatigue strength

Microwave curing technology: By reducing the content of residual monomers, microwave curing technology improves the mechanical properties of denture bases and may have a positive impact on fatigue strength.

Fiber distribution and stirring technology: The distribution of fibers and stirring technology are crucial to the enhancement effect. For instance, mechanical stirring of carbon fibers and PMMA powder before adding monomers can effectively address the issue of uneven fiber distribution, thereby enhancing fatigue strength.

Third, the influence of material properties on fatigue strength

Porosity and residual monomer content: Porosity and residual monomer content are important factors affecting the creep performance of PMMA. Reducing porosity and monomer residue can enhance the creep resistance, and thereby may increase fatigue strength.

Powder size and density: Increasing the powder size and density can enhance the creep resistance and have a positive impact on fatigue strength.