Soft acrylic resin materials containing a polymerisable plasticiser I: mechanical properties

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Conventional soft acrylic resins rely on plasticisers for flexibility, but these leach out in water, causing hardening.
• A previous attempt using polymerisable plasticisers failed due to mechanical weakness during clinical trials.
• Improving the mechanical integrity of soft lining materials is crucial for denture longevity and patient comfort.

Purpose of the Study:

• To reformulate a soft acrylic resin material to enhance its mechanical strength and durability.
• To investigate the effects of different methacrylate monomers and plasticiser concentrations on material properties.
• To compare the performance of the reformulated materials against a commercial soft lining material.

Main Methods:

• Three different methacrylate monomers were evaluated with two distinct plasticiser concentrations.
• Each monomer/plasticiser combination was tested at three powder/liquid ratios.
• Key mechanical properties including tensile strength, tear energy, and hardness were measured.

Main Results:

• All experimental soft lining materials exhibited superior tensile strength compared to the original formulation.
• Materials containing 30% plasticiser, particularly at higher powder/liquid ratios, demonstrated comparable strength, tear energy, and hardness to the commercial 'Supersoft' material.
• The reformulated materials achieved improved mechanical properties, overcoming previous limitations.

Conclusions:

• The reformulated soft acrylic resin materials demonstrate significantly improved mechanical strength.
• The use of specific methacrylate monomers and optimised plasticiser levels can create durable soft lining materials.
• These advancements offer a promising solution for developing more resilient and long-lasting denture soft liners.