Osteoradionecrosis and osteonecrosis (MRONJ) of the jaws .

  • Osteoradionecrosis and osteonecrosis of the jaws are complications of medical treatment. Osteoradionecrosis is the result of radiation trauma after radiotherapy, where osteonecrosis is related to antiresorptive (biphosphonates) and antiangiogenic medications. Both conditions are characterized by bone necrosis.
  • They may occur in any location of the jaws, but the mandible is more susceptible.
  • CT and CBCT are important examinations in order to detect early osseous changes and to  determine the extend of the lesion in the cancellous bone.
  • Radiographic features: radiolucency with ill defined or moth-eaten borders, cortex infiltration, osteosclerosis, periosteal bone formation and occasionally bone sequestrion resulting in a mixed (radiolucent/radiopaque) lesion.

Differential Diagnosis

Case 1

Osteoradionecrosis of the mandible due to radiation therapy, 12 years before.

Case 2

Osteoradionecrosis of the mandible in a female 67 years old.

Case 3

Osteonecrosis of mandible due to antiresorptive (bisphosphonates) medication.

Case 4

Osteonecrosis of  both maxilla and mandible due to antiresorptive (bisphosphonates) medication.

Case 5

Same patient as in case 4, eighteen months later.  A significant enlargement of the lesions in both maxilla and mandible is observed.