ABSTRACT
Objectives: The objective of the study was to evaluate fluoride release and water sorption of
three flowable esthetic restorative materials: a giomer, a fluoride-releasing resin
composite, and a nonfluoridated resin composite. Materials and Methods: Ten samples from a giomer, a fluoride releasing nano-hybrid, and a nonfluoridated
nano-hybrid composite were prepared and immersed in deionized water. Fluoride measurements
were done using an ion-specific electrode attached to a microprocessor-based fluoride
meter after 1 day, 1 week, and 4 weeks. Another thirty samples were made and placed
in desiccators. Water sorption was calculated by weighing the specimens before and
after water immersion for 1 day, 1 week, and 4 weeks. Data analysis was done using
two-way ANOVA, paired t-test (P < 0.05), and Pearson's correlation coefficient to calculate correlations between
fluoride release and water sorption. Results: The highest fluoride release was from giomer after 1 day, it was statistically significant
from all other groups. Both nano-hybrid composites after 1 day showed significantly
lower water sorption which was different than all the other groups. Pearson's correlation
showed no significant correlations between fluoride release and water sorption. Conclusions: Fluoride release is material and time dependent, while water sorption is material
dependent.
Key words:
Fluoride release - giomer - nano-hybrid composite - water sorption