the impact of nano-cellulose derived from husk rice, nano-hydroxyapatite and nd: yag laser on the re-mineralization of artificial enamel caries lesion in vitro

Dental caries is a complex process that is controlled by a variety of variables. there are a lot of exciting and promising uses for nanotechnology in the field of tissue repair especially in dental mineralized tissues. this study aimed to examine the remineralization impact of nanocellulose and nanocellulose/nanohydroxyapatite and effect of nd-yag laser on artificial caries lesions. this study involved two parts, first part includes preparation and characterization of prepared nanoparticles. then by using 57 first premolar teeth, the second part was conducted by measuring the effects of these prepared nanoparticles on enamel using vickers microhardness tester and scanning electron microscope (sem). artificial caries lesions were produced by immersing 57 teeth individually in a demineralizing solution for 72 hours. then the teeth were subjected to a 10-day ph cycle. samples were assigned to five groups: (1) control (2) teeth treated by nanocellulose (3) teeth treated by nanohydroxyapatite (4) teeth treated by nanocellulose/nanohydroxyapatite and (5) teeth exposed to laser then treated by nanocellulose/nanohydroxyapatite. surface microhardness and scanning electron microscope were performed prior to and after lesion formation then after treatment. there was a reduction in microhardness after demineralization as compared to sound teeth for all groups. after treatment with different agents, a marked increase in microhardness for all groups was found with a significant difference (p<0.05), with the maximum increase being in the group treated with laser- nanocellulose/nanohydroxyapatite. the enamel surface treated with prepared nanoparticles, and nd:yag laser, alone or combination yielded favorable results in increase microhardness, of the enamel surface.