# Hyperpure chlorine dioxide versus chlorhexidine in intra-oral halitosis (ODOR trial) – protocol of a double-blinded, double-arm, parallel non-inferiority pilot randomized controlled trial

## TL;DR

This study compares the effectiveness of hyperpure chlorine dioxide and chlorhexidine in reducing bad breath after tongue cleaning.

## Contribution

The study introduces a pilot trial to evaluate hyperpure chlorine dioxide as a potential non-inferior alternative to chlorhexidine for intra-oral halitosis.

## Key findings

- The trial will assess short-term effects of the interventions over a 3-hour period.
- Primary outcomes will be based on changes in organoleptic test scores.
- Sample size calculation will guide further enrollment if feasible.

## Abstract

Intra-oral halitosis (IOH) is the most common type of bad breath; its consequences impair quality of life. However, evidence-based treatment protocols and guidelines are lacking. Our aim is to investigate the effectiveness of chlorine dioxide as an applicable complementary treatment modality in IOH after tongue cleaning.

The ODOR trial will be a single-center, double-blinded, parallel-group, double-armed pilot randomized controlled trial with a non-inferiority design. The efficacy of hyperpure chlorine dioxide will be compared to chlorhexidine mouthwash. We plan to investigate the short-term effects of the intervention over a 3-h period. The primary endpoint will be changes in organoleptic test scores. At the end of the pilot investigation of the first 30 patients each, sample size calculation will be performed. If feasible, the investigators will continue the study by enrolling more patients.

The trial has been registered at ClinicalTrials.gov (NCT06219226).