Purpose: The study was established to compare the remineralization effect of
natural agents versus bioadhesive polymers with or without PH cycling using a
microhardness test. Materials and Methods: Forty extracted premolars were used.
The roots of the teeth were removed, then the crowns of teeth were cut in mesiodistal
direction to expose the labial and lingual portion using a diamond disc so that 80
specimens were obtained. Each tooth-half was fixed with superglue on the custom made
acrylic block. The enamel surfaces were polished to produce flat enamel surfaces. 80
specimens were divided into four groups (A) according to the remineralizing agent
used. Group A1 for eggshell nanoparticles, Group A2 for clove extract, and Group A3
for carbopol, and Group A4 for carboxymethyl cellulose (20 each). Each group was
subdivided into two subgroups (10 each) according to PH cycling either with (B1) or
without (B2). Then, the specimens were examined before and after demineralization
and after treatment agent with Digital Display Vicker Microhardness Tester.
Results: The results showed that the highest microhardness mean values were found
with eggshell nanoparticles followed by carbopol, and then carboxymethyle cellulose
then clove extract. Conclusion: Natural materials have remineralizing potentials and
could successfully replace synthetic products.