Nanocomposite based on poly(methyl-methacrylate) doped with molybdenum disulfide and its potential application as a dental material

Biocompatible nanocomposites represent a viable alternative to improve the properties of common dental materials. In this work, we report nanocomposites based on poly(methyl methacrylate) (PMMA) doped with molybdenum disulfide (MoS2) nanostructures. The MoS₂ nanostructures were synthesized via hydrothermal synthesis and subsequently incorporated into the PMMA matrix through in situ suspension polymerization, yielding PMMA/MoS₂ nanocomposites with MoS2 concentrations of 25, 50, and 100 µg/mL. XRD and FTIR analysis confirmed the successful polymerization and interaction between the MoS₂ nanostructures and the PMMA matrix. TGA analysis showed that the PMMA/MoS₂ composites exhibit thermal stability above 200 °C, UV–vis diffuse reflectance spectroscopy (DRS) of the PMMA/MoS₂ nanocomposites revealed a bathochromic shift, indicating a reduction in the optical band gap, in all nanocomposites, especially in the composites at 25 µg/mL and 50 µg/mL of MoS₂. This effect may be attributed to the effective dispersion of MoS₂ nanostructures within the PMMA matrix. These findings were supported by SEM analysis. Cytotoxicity tests conducted with human gingival fibroblasts (HGF) demonstrated that composites containing up to 100 µg/mL of MoS₂ may be biocompatible with HGF cells under acute exposure conditions, in both direct and indirect contact, making PMMA/MoS₂ composites promising candidates for potential dental applications.