Comparative analysis of hydrazinyl coumarin derivative incorporation in resin-modified and conventional glass ionomer cement

The study aimed to conduct a comparative analysis of the effects of incorporating hydrazinyl coumarin derivative (HCD) in resin-modified (RMGIC) and conventional glass ionomer cement (cGIC) on their release profiles and antibacterial properties.

Resin-modified GIC, Fuji II LC (F2) and high-fluoride cGIC, Fuji VII (F7) were used as controls. HCD was synthesized in-house, incorporated into both RMGIC and cGICs at 1 % and 2 % weight percentages (w/w), and chemically analyzed using Fourier transform infrared (FTIR) spectroscopy. Then, the F2 containing HCD (GIC-HCD F2) and F7 containing HCD (GIC-HCD F7) were evaluated for HCD and fluoride release profiles using UV Visible spectrophotometer and pH/ISE benchtop fluoridemeter, respectively. The antibacterial properties were assessed against Streptococcus sanguinis using the agar well diffusion method and measurement of bacterial growth turbidity, followed by the observation of the bacterial morphology using scanning electron microscope. The data were statistically analyzed using one-way ANOVA and Bonferroni post-hoc tests.

The FTIR spectra confirmed the presence of HCD in the GIC-HCD matrices. HCD was successfully released from both GIC-HCD F2 and GIC-HCD F7 matrices at both weight percentages. Higher fluoride release and inhibitory zones were observed compared to the control groups, with GIC-HCD F2 having a more significant effect than GIC-HCD F7. Additionally, the incorporation of HCD slowed down the growth of Streptococcus sanguinis and showed remarkable changes in bacterial shape specifically on GIC-HCD F2.

The incorporation of HCD into both RMGIC and cGIC improved fluoride release and enhanced the antibacterial activities, with a more significant effect observed in RMGIC compared to cGIC.