# Effect of energy drinks on the surface microhardness of bulk fill resins. In vitro study

## TL;DR

This study found that energy drinks reduce the surface hardness of dental resins over time, which could affect dental restorations.

## Contribution

The study introduces a novel in vitro comparison of surface microhardness changes in bulk fill resins exposed to specific energy drinks.

## Key findings

- Surface microhardness of all tested resins decreased significantly after exposure to energy drinks.
- Volt energy drink caused greater reductions in microhardness compared to Maltin Power after 30 days.

## Abstract

The study aimed to compare the surface changes of Filtek Z350XT, Filtek Bulk Fill, and Opus Bulk Fill resins immersed in Maltin Power® and Volt® energy drinks using surface microhardness testing.

This experimental study evaluated two types of bulk fill resins and Filtek resin (control). Forty-eight resin discs measuring 4x4 mm were prepared and soaked in 20 ml of an energy drink for 10 minutes daily for 7 and 30 days. Surface microhardness was assessed using the Vickers microhardness method. Repeated samples were analyzed using the ANOVA test, and multiple comparisons were conducted using the Bonferroni test. Finally, the Kruskal-Wallis test also was applied (P< 0.05).

The decrease in surface microhardness of the three resins exposed to the two energy drinks was significant (P<0.05). After immersion in the Volt energy drink over 30 days, the Filtek Z350XT, Filtek Bulk Fill, and Opus Bulk Fill resins showed decreases in surface microhardness of 3.89±1.94; 7.74±4.66 and 5.86±3.17, respectively, while the respective decreases after immersion in the Maltin Power energy drink were 3.67±4.08, 5.70±0.99, and 3.23±1.76.

Immersion in the energy drinks changed the surface microhardness of bulk fill resins after 7 and 30 days. Both clinicians and patients should consider these findings when determining the consumption frequency of these beverages.

Key words:Energy drink, hardness test, composite resins.