Comparative Evaluation of Mechanical, Optical and Surface Properties of Four Commercially Available Flexible Denture Base Materials on Water Absorption- An In Vitro Study

Comparative Evaluation of Mechanical, Optical and Surface Properties of Four Commercially Available Flexible Denture Base Materials on Water Absorption- An In Vitro Study - Aim: This study is oriented to evaluate the impact of water absorption on mechanical, optical, and surface properties of four commercially available flexible denture base resins. Materials and Methods: A total of 120 samples were prepared, with 24 samples for each of four resin types( Valplast, Lucitone FRS, Bre-Flex, and De-Flex) and 24 controls. Specimens followed ADA specification number 12 for flexural strength, surface hardness, surface roughness, and colour stability tests. Resin polymerization methods included auto-mix syringe injection for thermoplastics and compression moulding for PMMA. Results: Valplast exhibited the highest flexural strength consistently over time, followed by Lucitone FRS, PMMA, and De-Flex, with Bre-Flex showing the lowest resistance to bending. Valplast also maintained superior surface hardness compared to Lucitone FRS, which degraded over time. Valplast showed minimal surface roughness, enhancing aesthetics and comfort. Lucitone FRS displayed declining surface hardness, potentially impacting long-term durability with denture cleaners. Bre-Flex demonstrated exceptional colour stability, while Valplast also retained colour well. In contrast, De-Flex showed significant colour changes, raising durability concerns. Conclusion: Valplast demonstrated superior flexural strength, surface hardness, and surface roughness characteristics, making it highly suitable for long-term denture use. Bre-Flex excelled in colour stability but showed lower mechanical properties. Lucitone FRS exhibited good initial properties but suffered from reduced surface hardness over time. De-Flex's colour instability raises durability concerns. These findings highlight Valplast's overall favourable performance across multiple parameters crucial for denture base materials, emphasizing its potential for enhancing denture longevity and patient satisfaction. Keywords: Flexible Denture Base Material, Valplast, Lucitone FRS, Bre-Flex, De-Flex, Colour Stability, Flexural Strength