# Characterization of Newly Synthesized Nanobiomaterials for the Treatment of White Spot Lesions

## TL;DR

This study developed and tested new nanobiomaterials for treating white spot lesions in teeth, finding some to be more effective and biocompatible than existing commercial options.

## Contribution

The paper introduces four novel nanobiomaterials with optimized physicochemical and biocompatibility properties for treating dental white spot lesions.

## Key findings

- NB6 and NB6F showed the highest polymerization potential, while NB3 had the lowest water absorption and solubility.
- NB3 and NB6 exhibited higher cell viability than the commercial material Icon®, indicating better biocompatibility.
- Fluoride release varied with formulation, with NB3F releasing the least on day 7 despite containing UDMA.

## Abstract

Background: White spot lesions (WSLs) are characterized by enamel demineralization. Minimally invasive treatments using infiltrating resins, such as the commercially available Icon®, are recommended. The need for such treatments justifies ongoing research into developing materials that can address existing limitations regarding strength, durability, and biocompatibility. Objectives: This study aimed to synthesize and characterize four novel nanobiomaterials by evaluating their physicochemical properties and biocompatibility compared to the commercial material Icon®. Materials and methods: The recipes for the experimental nanobiomaterials NB3, NB6, NB3F, and NB6F contain varying proportions of TEGDMA, UDMA, HEMA, Bis-GMA, and HAF-BaF2 glass. Mechanical and physicochemical characteristics were evaluated, such as flexural strength, measured using the three-point test; water absorption and solubility; fluoride release; polymerization conversion; and residual monomers, assessed using High-Performance Liquid Chromatography (HPLC). In vitro cell viability was assessed via colorimetry using human dysplastic oral keratinocytes (DOKs). Results: NB6 and NB6F demonstrated the greatest polymerization potential. NB3 exhibited the lowest water absorption and solubility due to its hydrophobic nature. Additionally, the inclusion of UDMA enhanced the strength and elasticity of NB3 when compared to NB6. Among the samples with fluoride additives (NB3F and NB6F), the highest fluoride release on day 7 occurred with the material lacking UDMA. In contrast, the NB3F sample containing UDMA released the least amount of fluoride on the same day. In quantitative terms, NB3 and NB6F exhibited the lowest levels of residual monomers, whereas NB6 showed the highest levels. Both NB3 and NB6 were significantly better tolerated by the cells, showing higher cell viability compared to the commercial material Icon®. Conclusions: The materials’ mechanical and physicochemical properties varied with component proportions, enabling identification of a suitable formulation for targeted clinical applications. Biocompatibility tests showed that the experimental NB3 and NB6 were better tolerated than Icon®. Furthermore, the incorporation of filler particles improved the mechanical strength of the experimental nanobiomaterials.