First intraoral use of therapeutic oxygen carrier Hemarina-M101 for mandibular osteoradionecrosis: a case report.

Osteoradionecrosis of the jaw (ORN) remains a challenging complication of head and neck radiotherapy, with limited effective therapeutic and preventive options. Hemarina-M101 is a natural extracellular hemoglobin derived from Arenicola marina, with documented effects on tissue oxygenation and wound healing. However, it has not previously been applied intraorally. To our knowledge, this report describes the first intraoral use of Hemarina-M101 oxygenating dressing (H-MOD) in two patients with advanced mandibular ORN treated under compassionate-use authorization. Two different application protocols were used according to clinical constraints. In both patients, intraoral application was feasible and no immediate complications directly attributable to the treatment were observed. In Patient 1, partial mucosal healing was observed, although disease progression occurred during follow-up. In Patient 2, complete mucosal healing was achieved at 6 months, with no residual bone exposure. Given the descriptive nature of this report, no conclusion can be drawn regarding its therapeutic efficacy. Further prospective studies, particularly in preventive settings such as dental extractions in irradiated patients, are warranted.