Comparison of Hyaluronic Acid and Chlorhexidine Gels for Traumatic Oral Ulcers During Fixed Orthodontic Treatment (HYCHO-TOU)

Traumatic oral ulcers are among the most common adverse effects experienced during fixed orthodontic treatment. They usually occur due to continuous mechanical irritation of the oral mucosa by orthodontic brackets, archwires, or other appliance components. These lesions may cause pain, interfere with mastication and speech, and reduce patient comfort and compliance with orthodontic treatment. Although traumatic ulcers generally heal spontaneously after removal of the source of irritation, topical agents are frequently prescribed to accelerate healing and relieve symptoms.

Hyaluronic acid is a naturally occurring glycosaminoglycan with anti-inflammatory, tissue regenerative, and wound-healing properties. It promotes cell migration, angiogenesis, and extracellular matrix formation, thereby facilitating mucosal repair while reducing pain and inflammation. Chlorhexidine gel is a widely used topical antiseptic that reduces bacterial colonization of oral wounds and helps prevent secondary infection during the healing process. Although both agents are commonly used in dental practice, evidence directly comparing their effectiveness in the management of orthodontic traumatic oral ulcers remains limited.

This study is designed as a single-center, parallel-group, randomized controlled trial conducted in the Department of Orthodontics, DIKIOHS. Thirty patients aged 13-35 years who develop traumatic oral ulcers following placement of fixed orthodontic appliances and meet the eligibility criteria will be enrolled. Participants will be randomly assigned in a 1:1 ratio using the lottery method to receive either topical hyaluronic acid gel or topical chlorhexidine gel.

Participants in both groups will be instructed to apply approximately a grain-sized amount of the assigned gel directly onto the ulcer using a clean finger or cotton swab three times daily for seven consecutive days. They will be advised to avoid eating, drinking, or rinsing immediately after application to maximize contact time with the lesion.

Clinical assessments will be performed at baseline (Day 1), Day 3, and Day 7. At each visit, ulcer location, clinical appearance, ulcer size (measured in millimeters using a transparent ruler), and pain intensity (measured using a Visual Analog Scale) will be recorded. The primary outcome will be reduction in pain intensity, while secondary outcomes will include reduction in ulcer size and clinical healing over the seven-day treatment period.

The findings of this study are expected to provide evidence regarding the comparative effectiveness of hyaluronic acid gel and chlorhexidine gel for the treatment of traumatic oral ulcers associated with fixed orthodontic appliances. The results may assist orthodontists in selecting the most effective topical treatment to improve patient comfort, promote faster healing, and enhance adherence to orthodontic treatment.