Revolutionising oral mucositis treatment: Antibacterial light-activated therapy in future protocols

By Dr Matti Mauramo and Prof Tuomas Waltimo

INTRODUCTION

Oral mucositis, an inflammation of the oral mucosa, often occurs in association with cancer treatments, particularly radiation and chemotherapy. It manifests as severe pain, redness, and swelling in the patient’s mouth, potentially impacting the success of cancer therapy. To date, no existing medication has effectively prevented the development of mucositis. Recent research suggests that antibacterial dual light therapy may be an effective method to manage the symptoms of this condition.

Traditional approaches to treating oral mucositis include preventive measures such as maintaining good oral hygiene and ice therapy during chemotherapy. If bacterial infection is present, the use of antibiotics may be considered by the physician. Corticosteroids are also a treatment option to alleviate pain and the inflammatory response associated with mucositis. However, corticosteroid use poses risks, as it can suppress the immune system, making cancer patients more susceptible to infections.1,2

Ongoing research explores novel methods for preventing and treating oral mucositis. Mitochondria stimulating red-light therapy has proven to be very effective in treating oral mucositis, particularly as a preventive measure. Although light therapy is estimated to be the most effective treatment modality, its widespread implementation faces challenges such as availability and practical issues.3

oral mucositis
Fig. 1: After this cycle, the photosensitiser is back in the ground state and ready to absorb a new photon

The latest studies investigate antibacterial treatments to preventively address oral mucosal ulcers originating from mucositis, aiming to mitigate the adverse effects of aggressive cancer treatments.

IMPROVING PATIENT QUALITY OF LIFE

In the bachelor’s thesis from the Faculty of Medicine at the University of Helsinki titled ‘Oral Mucositis – Antibacterial Dual Light in the Treatment of Oral Mucositis’, medical student Jessica Hentilä explores the effects of antibacterial photodynamic therapy (aPDT) and antibacterial blue light (aBL) on mucositis ulcers as local treatments.3

Hentilä’s research evaluates the efficacy of dual light therapy against Streptococcus Oralis — a common bacterium in the oral microbiome. Bacterial colonies form over ulcers on the oral mucosa from the mouth’s own bacterial flora. Drawing of the mechanism of action of aPDT, the study indicates that antibacterial dual light, a combination of aPDT and aBL, not only effectively targets streptococcal infections found in mucositis-induced ulcers but provides red light therapy simultaneously (Fig. 1).

The target tissue is treated with a selected photosensitiser and is irradiated with visible light. The photosensitiser absorbs the photon of visible light and is raised to a higher energy state from its ground state. From this higher energy state, the photosensitiser can either lose its energy and return to the ground state, or it can be raised to an even higher, more permanent level. From this higher, more permanent level, it can return to the ground state either by phosphorescence emission or by producing reactive oxygen species (ROS).

oral mucositis
Fig. 2: Mucositis incidence depending on cancer type and mode of therapy. Data extracted from Pulito et al8

According to Dr Tommi Pätilä, the thesis advisor of Hentilä’s project and specialist in paediatric heart and organ transplantation surgery, the reduction of oral bacterial load in the mouth promotes mucosal wound healing, concurrently reducing the risk of local and systemic infection complications common in cancer patients (Fig. 2). This is an important addition to the conventionally applied red light therapy.3

Oral mucositis is a prevalent side effect in cancer patients undergoing chemotherapy, radiation therapy, or combined chemo-radiation therapy. Its pathophysiology stems from the ability of cancer treatments to inhibit rapidly dividing cells, present not only in cancer tissues but also in the oral mucosa.4,5

Clinically, oral mucositis induces an inflammatory reaction in the oral mucosa, leading to swelling, redness, and painful ulcers.5 These mucosal variations create an entry point for oral bacteria, exacerbating mucositis-related inflammation or potentially spreading to other parts of the body.

Alongside mucosal inflammation, cancer treatments often induce dry mouth, exposing cancer patients to various other oral diseases as well, such as tooth decay, gingivitis, and challenging periodontal and peri implant diseases.4,5

To read the full article, click here or refer to Dental Asia March/April 2024 issue.

ABOUT THE AUTHORS

Dr Matti Mauramo

Dr Matti Mauramo is a comprehensive oral healthcare professional, PhD, dentist, and a specialised physician, holding a DDS degree and a MD degree. As a dentist, he has been working since 2004 in both public and private sectors, including specialised healthcare settings such as the Oral Specialized Care Unit in the City of Helsinki and at the University of Basel in Switzerland. Currently, Dr Mauramo works as a specialised physician, a clinical instructor in medicine, and conducts research on oral diseases in patients with blood cancers.

Prof Tuomas Waltimo

Prof Tuomas Waltimo is an experienced healthcare professional and clinical university professor specialising in oral health and medicine. He holds qualifications in prevention, operative dentistry, and experimental microbiology, with expertise in clinical dentistry. Proficient in clinical, in vitro, and epidemiological research, with a proven track record in diverse clinical and research environments, Prof Waltimo is internationally recognised as a clinician and scientist, particularly in supportive care in cancer over the last two decades.