Plant-derived multimethacrylate dendritic monomers: Synthesis and applications in dental restorative resins.

Regarding the global increase in dental caries, the development of high-quality resin-based materials is essential. However, it is still a challenge to alleviate the polymerization shrinkage of methacrylate monomers. Herein, we constructed the first- and second-generation betulin-based multimethacrylate dendritic monomers (D1, D2, and D3) via the esterification reaction, which were differed primarily in the number and position of the terminal methacrylate groups. These photo-polymerizable dendritic monomers were introduced as the partial (10 wt%) and total (50 wt%) replacements of bisphenol A glycidyl dimethacrylate (Bis-GMA) in dental restorative resins. Notably, the D14B5T resin, composed of 10 wt% D1, exhibited a significantly lower shrinkage (8.02 ± 0.28 %; 17 % reduction) and improved flexural strength and modulus (87.4 ± 0.8 MPa, 1.9 ± 0.1 GPa) than the commercial resin (9.66 ± 0.29 %; 82.1 ± 0.5 MPa; 1.6 ± 0.1 GPa), due to its well-balanced crosslink density and structure properties. Molecular dynamics simulation of these two resins provided mechanistic insights to how the monomer structure affecting the resin shrinkage. The optimal D14B5T resin also possessed better fluidity, cell viability, and acceptable polymerization conversion compared to the commercial control. This study provides new insights into the synthesis of plant-derived polymerizable dendrimers and the creation of high-performance dental resins, endowing them promising for biomedical fields such as teeth restorations.