Physicomechanical properties and polymerization shrinkage of the newly developed radiopaque flowable composite derived from rice husk

Abstract The study aimed to evaluate the physicomechanical properties and polymerization shrinkage of the newly developed flowable composite (FC). The physical and mechanical properties assessed include flowability, radiopacity, depth of cure, surface roughness, compressive strength, and compressive modulus. The newly developed FC was prepared by incorporating zirconia as a radiopacifying agent and nanohybrid silica derived from rice husk as fillers, with the monomer ratio of urethane dimethacrylate to triethylene glycol dimethacrylate (UDMA:TEGDMA) manipulated at 20:80, 30:70, 50:50, 60:40, 80:20, and 90:10. Filtek Supreme Ultra Flowable Restorative, Revolution Formula 2 and G‐aenial Universal Flo served as control groups. The data were statistically analyzed using one‐way ANOVA and post‐hoc Tukey tests. The newly developed FCs, with flowability levels classified as high, medium, and low‐flow, were found to be radiopaque. As the UDMA ratio in the newly developed FCs increased, depth of cure, compressive strength, and compressive modulus increased, while surface roughness and polymerization shrinkage decreased. Comparable values were observed between the newly developed FCs and control groups in flowability, surface roughness, compressive modulus, and polymerization shrinkage. In summary, the newly developed radiopaque FCs could serve as sustainable dental restorative materials by enhancing diagnostic accuracy, improving physicomechanical properties, and minimizing polymerization shrinkage. Highlights Different UDMA:TEGDMA ratios were crucial in determining the properties The three different levels of flowability were confirmed to be radiopaque Higher ratio of UDMA improved the physical and mechanical properties Higher ratio of UDMA reduced the polymerization shrinkage