RESUMO
AIM: The present study evaluated the effect of LLLT at red and infrared wavelengths associated with therapeutic measures from the Mucositis Study Group of the Multinational Association of Supportive Care of Cancer and International Society of Oral Oncology (MASCC/ISOO) for preventing and treating RT-induced oral mucositis (OM). MATERIALS AND METHODS: For the study, 80 subjects diagnosed with head and neck cancer (HNC) undergoing treatment were randomized into three groups to apply different photobiomodulation protocols for 42 days, as follows: Group I-LLLT of 660 nm; Group II-LLLT of 810 nm; and Group III-association of wavelengths of 660 and 810 nm. The treatments were performed by properly trained professionals and with equipment calibrated for the intervention. RESULTS: Different OM scores were noted for the groups studied, and the third group had lower scores than Groups I and II (p = 0.012). No difference was noted in the pain score analyzing the groups (p = 0.49). CONCLUSION: The LLLT was effective for OM lesions in individuals treated with radiotherapy associated or not with chemotherapy. When combined, the red and infrared lasers reduce OM scores. CLINICAL SIGNIFICANCE: OM is one of the main adverse effects of antineoplastic therapy in head and neck cancer patients. The evidence supporting the validity of LLLT for OM can improve patients' quality of life.