Dynamic viscoelastic properties of processed soft denture liners: Part I--Initial properties

Area of Science:

• Materials Science
• Biomaterials Engineering
• Dental Materials Science

Background:

• Soft denture liners are crucial for patient comfort and function.
• Understanding their dynamic viscoelastic properties is essential for material selection and performance prediction.
• Previous research has not comprehensively evaluated a wide range of materials under clinically relevant conditions.

Purpose of the Study:

• To evaluate and compare the dynamic viscoelastic properties of 12 laboratory-processed soft denture liners.
• To determine the influence of temperature and strain frequency on these properties.
• To identify materials with optimal properties for denture applications.

Main Methods:

• Dynamic viscoelastic properties (storage modulus, loss modulus, damping factor) were measured using a custom dynamic viscoelastometer.
• Specimens were tested at 23°C and 37°C with strain frequencies of 1, 5, and 10 Hz.
• Statistical analysis was performed using ANOVA and Scheffe's intervals test.

Main Results:

• Significant differences in storage modulus (elastic stiffness) and loss modulus (viscous behavior) were observed among the 12 materials.
• Verno-Soft demonstrated significantly higher storage and loss moduli compared to other materials.
• Acrylic and vinyl resins generally exhibited higher damping factors than silicone and polyphosphazine rubbers.
• Temperature and strain frequency influenced the viscoelastic properties of some materials.

Conclusions:

• Material choice significantly impacts the dynamic viscoelastic performance of soft denture liners.
• Verno-Soft exhibits distinct viscoelastic characteristics potentially offering superior performance.
• Soft denture liner properties are sensitive to environmental factors like temperature and mechanical loading frequency.