Comparable efficacy of extraoral and intraoral photobiomodulation in preventing oral mucositis during high-dose methotrexate therapy in pediatric oncology: A single-blind randomized controlled trial

This prospective randomized controlled clinical study compared intraoral (IO) and extraoral (EO) photobiomodulation (PBM) for the prevention of chemotherapy-induced oral mucositis (OM) in pediatric oncology patients.

A total of 155 patients (1-18 years), receiving high-dose methotrexate (HDMTX) for leukemia, lymphoma, or osteosarcoma, were randomized to PBM-IO (n = 73) or PBM-EO (n = 82). Preventive PBM was administered daily from hospital admission through discharge. Both protocols used red light with equivalent dosimetry (660 nm, 100 mW, 1 J per point). PBM-EO required 30 s/session, whereas PBM-IO required approximately 6 min, excluding patient handling time. OM occurrence, severity (WHO scale), plaque index, and pain (numeric rating scale) were assessed on days 0, 3, 5, and 10 after HDMTX infusion.