degree of conversion of resinmodified glass ionomer cement containing hydroxyapatite nanoparticles

Objectives: hydroxyapatite (ha) nanoparticles are used to improve the physical and mechanical properties of glass ionomers (gis). this study aimed to assess the effect of addition of different weight percentages of nanoha on degree of conversion (dc) of fuji ii lc gi cement using a spectrometer.materials and methods: in this in vitro experimental study, 30 samples were fabricated of fuji ii lc (improved) gi cement in six groups (n=5) containing 0%, 1%, 2%, 5%, 7% and 10wt% nanoha. the obtained paste in each group was subjected to fouriertransform infrared spectroscopy (ftir) before curing to assess the monomer to polymer dc percentage. the paste was then lightcured and underwent ftir again. oneway anova was applied to compare the dc percentage of different groups. pairwise comparisons were performed using the tukey’s test.results: the dc was 57.88±0.57% in 0%, 60.04±0.63% in 1%, 66.92±0.54% in 2%, 65.5±0.71% in 5%, 51.49±0.24% in 7% and 50.09±0.32% in 10% nanoha group. the difference in dc among the groups was statistically significant (p<0.0001). the highest dc was noted in 2% nanoha and the lowest dc was found in 10% nanoha group. pairwise comparisons revealed significant differences between the groups in dc (p<0.0001).conclusion: increasing the weight percentage of nanoha to 2% increased the dc but increasing the nanoha weight percentage over 5% decreased the dc of resinmodified glass ionomer cement (rmgic). the highest dc was noted in 5w% and 2w% nanoha groups. thus, 5w% and 2w% nanoha can be used to improve the dc of rmgic.