Mandibular osteoradionecrosis is more common than other forms of radiation osteonecrosis after radiation therapy for head and neck malignancies due to the superficial position of the mandible, which exposes it to high radiation. The maxilla can also be involved, but this is less frequent.
On this page:
Epidemiology
Mandibular osteoradionecrosis may occur in ~20% (5-37%) of patients 2,4.
Pathology
Mandibular osteoradionecrosis typically occurs in a patient who has received a dose of >60 Gy 4. Osteoradionecrosis changes may occur within a year of therapy.
Radiographic features
Features include 2,4:
cortical destruction that is ill-defined resulting in a mixed sclerotic-lucent pattern
sequestration, especially of the buccal bone
an absence of soft tissue mass is an important feature to differentiate it from neoplastic recurrence but the presence of soft tissue does not exclude osteoradionecrosis
Treatment and prognosis
Conservative treatment is initially medication only (e.g. pentoxifylline, vitamin E) but more severe cases may require hyperbaric oxygen therapy and/or debridement. Some patients will require resection and reconstruction of the mandible 3.
Given dental extractions increase the patients risk of developing mandibular osteoradionecrosis It is not uncommon to perform an OPG prior to treatment to rule out any potential dental abnormalities 5.
Complications
infection
radiation-induced neoplasia