Medication-related Osteonecrosis of the Jaw (MRONJ)

Self Study

What type of medications must a patient have a history of using to meet the diagnostic criteria for MRONJ?

Anti-resorptive or antiangiogenic agents, alone or in combination with immune modulators and antiangiogenic medications.

What is the key clinical finding required for MRONJ diagnosis?

Exposed bone or bone that can be probed through a fistula(e) in the maxillofacial region persisting for more than 8 weeks.

How long must exposed bone persist to meet the criteria for MRONJ?

More than 8 weeks.

What history must be absent in a patient for a diagnosis of MRONJ?

No history of radiation therapy or metastatic disease to the jaws.

What type of diagnosis is MRONJ?

Clinical- imagining is supportive and can help determine extent of disease

What is not required to make a diagnosis for MRONJ?

Histopathology because it is not entirely diagnostic

What is helpful in guiding antibiotic choice in cases of secondary bacterial infection

Culture and sensitivity testing, sometimes laboratory testing but it is not definitive

What do osteoclasts do?

Break down bone mineral and matrix, creating an erosion cavity

What do mononuclear cells do?

They prepare the bone surfacfe for new osteoblasts to begin building bone

What do osteoblasts do?

Form a matrix to replace resorbed bone with new bone

What is the resting period of bone metabolism?

A prolonged resting period follows until a new remodeling cycle begins

What are the goals of anti-resorptive therapy?

Prevent bone resorption and increase bone density