Material Science & Technical Characteristics of Flexible Dentures

1. Core Material Composition
Flexible dentures are fabricated using thermoplastic polyamide resins (e.g., Nylon 12) or copolyester materials, processed via injection molding. The amide groups in their molecular structure provide flexibility, while aromatic rings enhance wear resistance.

 

2. Key Technical Parameters

Flexural Modulus: 800–1,500 MPa (vs. 2,000–3,500 MPa for traditional acrylic)

Shore D Hardness: 75–85 (close to human gingival hardness)

Heat Deflection Temperature: 120–140°C (requires specialized heating equipment for adjustments)

Water Absorption Rate: <0.5% (minimizes dimensional changes during long-term use).

 

3. Manufacturing Advantages

Digital Workflow: Integrates intraoral scan data with CAD/CAM for precision design

Metal-Free Clasps: Achieves mechanical retention through material elasticity, avoiding metal fatigue fractures

Rapid Adjustability: Localized heating enables morphological modifications (must stay below 80°C to prevent degradation).

 

4. Technical Limitations

Stress Relaxation: 0.1–0.3 mm/year creep under prolonged mastication loads

Color Stability Challenges: 2.3× higher adsorption coefficient for tea polyphenols/nicotine compared to acrylic

Fabrication Accuracy Constraints: 0.8% injection shrinkage requires 0.5 mm machining allowance