# Effect of ionizing radiation on the mechanical properties of current fluoride-releasing materials

## TL;DR

This study found that ionizing radiation increases surface roughness of fluoride-releasing dental materials and affects their hardness and strength differently.

## Contribution

The novel contribution is evaluating how fractional radiation doses impact mechanical properties of various fluoride-releasing dental materials.

## Key findings

- Surface roughness increased in all groups after radiation exposure.
- Vickers microhardness decreased in F9 and EQ, but compressive strength increased in F2 and AC.
- AC showed the lowest surface roughness and highest compressive strength among materials.

## Abstract

This study aimed to evaluate the effect of fractional radiation on the mechanical properties of fluoride-releasing materials.

High-viscosity glass ionomer cement (F9), resin-modified glass ionomer cement (F2), glass hybrid restoration (EQ), and bioactive composite (AC) were divided into 3 subgroups: 0, 35, and 70 Gy fractional radiation doses. The specimens were subjected to surface roughness, Vickers microhardness, and compressive strength tests. The chemical components and morphology of the tested specimens were observed via energy dispersive spectroscopy and scanning electron microscopy. The data were analyzed using two–way ANOVA with Bonferroni post hoc analysis.

After exposure to fractional radiation, the surface roughness increased in all the groups. F9 had the highest surface roughness, while AC had the lowest surface roughness within the same radiation dose. The Vickers microhardness decreased in F9 and EQ. The AC had the highest compressive strength among all the groups, followed by F2. More cracks and voids were inspected, and no substantial differences in the chemical components were observed.

After fractional radiation, the surface roughness of all fluoride-releasing materials increased, while the Vickers microhardness of F9 and EQ decreased. However, the compressive strength increased only in F2 and AC.