Surface Characterization and remineralization Potential of Dental Floss Coated with Nano-Hydroxyapatite and Sodium Fluoride, An In-Vitro Study

Abstract

Objective: To evaluate and compare the remineralization potential of Nano hydroxyapatite (HAP) and sodium fluoride (NaF)– coated dental floss on demineralized enamel surfaces of sound teeth.

Methodology: This experimental study was conducted on sound extracted teeth using untreated, Nano hydroxyapatite (Nano-HAP)-coated, and sodium fluoride (NaF)–coated dental floss, after taking approval from the ethical committee of Islamic International Dental College from Feb 2024 to August 2024. Sound teeth (Absence of caries, cracks, abrasion, restorative materials, hypoplasia, white spot lesion, staining and other enamel defects). Non-Carious teeth extracted for orthodontic cases were included in the study through convenience sampling technique. While the carious, deciduous, and fractured teeth were excluded from the study. Samples were tested at 7, 14, and 21 days with regular flossing in artificial saliva. Enamel changes were analyzed using Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy (EDS). 

Results: Scanning Electron Microscope (SEM) confirmed successful deposition of Nano-HAP and NaF coatings on dental floss, with distinct morphological characteristics. EDS verified their elemental composition, demonstrating the presence of calcium and phosphorus in Nano-HAP and sodium and fluorine in NaF. Enamel treated with Nano-HAP showed earlier and more uniform remineralization, smoother morphology, and higher Ca/P ratios across 7, 14, and 21 days, while NaF exhibited slower deposition with gradual surface improvements over time.

Conclusion: Both Nano- hydroxyapatite- coated and sodium fluoride -coated dental floss enhanced enamel remineralization, yet Nano- hydroxyapatite exhibited superior and earlier effects, highlighting its potential as a biocompatible alternative to fluoride in preventive oral care.  

Keywords: Artificial saliva, Dental floss, Enamel remineralization, Fluoride, Microscopy, Nano-hydroxyapatite