Osteoradionecrosis (ORN) is the most worrying radiotherapy late complication. It is a condition in which the irradiated bone becomes devitalized and exposed through fistulas in the skin or mucosa. It remains without healing for a period of at least three months. Despite being a well-known entity to the professionals who treat neoplasms of the head and neck, the disease has many controversies. From its classifications to its best treatment plan. Its main signs and symptoms are pain, drainage of secretion, fistulas, ulcers of the oral mucosa, bone exposure, bone necrosis, and the surrounding soft tissue. This study aims to report a clinical case of a patient with ORN in the jaw treated at Bahiana School of Medicine and Public Health and the General Roberto Santos Hospital. A 60-year-old-male patient with a malignant neoplasm in the tonsil region, was diagnosed with ORN in mandible region, three years after radiotherapy. The treatment proposal was conservative (ozone therapy, hyperbaric oxygen and chlorexidine mouth rinse) associated with surgical debridement, with good results that involved the patient’s rehabilitation. It is concluded that the association of conservative therapies with surgery demonstrated satisfactory results and improving the quality of life of cancer patients with ORN.