# Evaluation of a Hydrodynamic Ozonation System for Gutta-Percha Disinfection and Structural Characterization

## TL;DR

This paper evaluates a hydrodynamic ozonation system for disinfecting gutta-percha in dental procedures, finding it effective and safe.

## Contribution

The study introduces hydrodynamic ozonation as a novel disinfection method for gutta-percha that preserves material integrity.

## Key findings

- Seven-minute exposure to ozonated water completely inactivated Enterococcus faecalis on gutta-percha.
- Ozonation preserved tensile strength and reduced elastic modulus, improving anatomical adaptation.
- FTIR and SEM analyses showed minimal structural and morphological changes in the gutta-percha.

## Abstract

Gutta-percha (GP), composed of the trans-isomer of polyisoprene,
is widely used in endodontic obturation due to its favorable sealing
properties. However, it is susceptible to contamination upon exposure
to the clinical environment, and its thermoplastic nature precludes
thermal sterilization. Conventional disinfection methods using sodium
hypochlorite (NaOCl) or chlorhexidine (CHX) require strict control
of concentration and exposure time to avoid structural damage. This
study evaluated the efficacy of a hydrodynamic system using ozonated
water for the inactivation of Enterococcus faecalis. Experimentally contaminated cones were exposed to a continuous
flow of ozonated water for 5 and 7 min, followed by microbiological
analysis. A seven-minute exposure (57.2 mg/L) resulted in complete
bacterial inactivation, enabling further characterization of the biomaterial
via FTIR spectroscopy, optical profilometry, scanning electron microscopy
(SEM), and tensile strength testing. FTIR revealed subtle changes
without compromising the polymeric backbone, while profilometry indicated
a significant reduction in surface roughness. Mechanical testing showed
preserved tensile strength and a reduction in elastic modulus, suggesting
improved anatomical adaptation. SEM analysis did not reveal any relevant
morphological alterations. These findings suggest that the hydrodynamic
ozonated water system is an effective and safe alternative for disinfecting
endodontic materials, with promising clinical applications.