Molecular dynamics simulation of polymerization kinetics, dimensional stability, and in silico toxicity of nextgeneration silicone impression materials in dentistry

This study evaluates how next-generation silicone impression materials intended for dental use behave during polymerization, as well as their dimensional stability, mechanical properties, degradation patterns, and in silico toxicity levels. Silicone materials are preferred for dental applications because of their outstanding mechanical properties and compatibility with biological tissues. The performance of these materials is susceptible to environmental conditions including temperature changes, humidity levels, and exposure to oral fluids. Patient safety requires evaluation of degradation product toxicity concerns. It is crucial to examine these properties at the molecular level to enhance material durability and safety during clinical use. The structural, mechanical, and stability properties of silicone materials were modeled through molecular dynamics (MD) simulations using BIOVIA Materials Studio 2020. Material characterization and evaluation of mechanical properties were performed with the Forcite module using the COMPASSIII force field. The study simulated polymerization dynamics to understand the reaction mechanisms while employing the Kinetix and DMol3 modules to analyze dimensional stability under various environmental stresses. The CASTEP and DMol3 modules, along with the OSIRIS DataWarrior, were employed to forecast degradation pathways and potential toxicity. The combination of an elastic modulus of 2.533 GPa and tensile strength of 5.387 MPa allows Polydimethylsiloxane (PDMS) to show superior flexibility and rigidity, which qualifies it as the best choice for dental impression materials. Methacryloxypropyltrimethoxysilane (3.248 GPa) and hexaphenylcyclotrisiloxane (3.017 GPa) exhibited enhanced stiffness, suggesting their usefulness in load-bearing scenarios. In silico toxicity predictions indicated that most silicone derivatives demonstrated acceptable biocompatibility, although some silane compounds showed potential risks requiring further experimental validation. Under simulated conditions, the materials maintained stable configurations and exhibited positive polymerization dynamics, indicating that they could provide high durability along with dimensional stability for dental usage. This study highlights the superior balance of flexibility, rigidity, and safety exhibited by PDMS, while also identifying Methacryloxypropyltrimethoxysilane and hexaphenylcyclotrisiloxane as candidates for specialized load-bearing dental applications. Promising in silico findings require experimental validation and clinical testing to establish their practical applications.