Osteonecrosis of the Jaw

What is osteonecrosis of the jaw?

Osteonecrosis is a process in which bone cells deteriorate and die. Osteonecrosis of the jaw (ONJ) occurs specifically in the cells of the maxilla and mandible jaw bones. This is a rare condition associated with dental extractions and bone therapies often used in cancer treatments, and occurs when jaw bones become uncovered by the gums and lose adequate blood flow.

Symptoms that may indicate a developing case of ONJ include pain, redness and tenderness of the jaw, jaw numbness, bad breath, development of an infection, and difficulty eating and drinking. Once ONJ has developed, usually over eight weeks, the primary symptom is lesions that expose bone.

Surgery or surgeries to remove the affected bone is often necessary with ONJ. Other less invasive treatments may include antibiotics and over-the-counter pain medication.

You should visit your primary care physician. This condition is usually treated conservatively with rinses, antibiotics, and pain medication for the mouth.

Osteonecrosis of the jaw symptoms

The primary symptom of ONJ is the exposure of the mandible or the maxilla to the air through lesions that cut to the bone. However, before ONJ becomes that severe, you may experience the following symptoms:

• Pain
• Redness and tenderness
• Numbness
• Bad breath
• Difficulty eating and drinking
• Development of systemic infections: These can be bacterial, fungal, or viral.

Causes of osteonecrosis of the jaw

The bones and bone marrow of the human body are made up of cells that require good blood supply in order to stay healthy. If blood flow to these bone cells is compromised or decreases, the cells will be stripped of necessary nutrients and may die. This deterioration and death of the bone cells is a process known as osteonecrosis. Osteonecrosis of the jaw occurs when an area of the jaw bone becomes uncovered by the gums and is exposed to the air. Main causes include dental procedures and bisphosphonate use.

Dental procedures

Dental procedures may lead to development and worsening of ONJ because the condition creates an environment that is easily susceptible to bacterial growth.

• Dental extractions: These are usually performed because of infections of the teeth and gums. Infections can spread after the procedure and cause bacteria to grow deep within the bones. Growth of bacteria in the bone can cause inflammation and further affect blood flow to these areas.
• Dental surgeries: These are also commonly performed to assess other maladies of the mouth, such as infections or to add implants.Improper surgical techniques or complications that introduce or spread bacteria can lead to ONJ.

Bisphosphonates

Bisphosphonates are treatments that specifically target the bones for certain conditions. They create the most risk for developing ONJ, and the longer they are taken, the greater the risk. The exact mechanism for why bisphosphonate use leads ONJ is unknown; however, the current hypothesis is that bisphosphonates decrease the bone's ability for self-repair and also may decrease blood vessel formation.

People who are diagnosed with the following conditions below are most likely to be taking bisphosphonates:

• Multiple myeloma: This is a cancer that forms in white blood cells.
• Metastatic cancers: Such as cancers that started in another organ but have spread (metastasized) to the bone.
• Osteoporosis: A condition where the bones become brittle and fragile from loss of tissue, typically as a result of hormonal changes/older age, or deficiency in calcium or vitamin D.
• Osteopenia: This condition is also related to bone loss and is often considered a lesser form of osteoporosis.

Treatment options and prevention

The first-line treatment option for ONJ is surgical removal of the bone; however, other treatment options are currently being explored for less severe cases. The best options include:

• Curettage: This is a process of removal that slowly scrapes and scoops away the affected tissue and bone. It has been found to work well for ONJ.
• Antibiotics: Although this condition is often related to infection, it is difficult to treat with antibiotics as there is little to no blood supply to the bone, making it difficult for the antibiotics to reach the potential infection. However, antibiotics are often used to treat mild to moderate cases of ONJ.
• Oral rinses and painkillers: In cases of ONJ related to osteoporosis, conservative treatment with rinses and oral painkillers have proven to be effective.
• Additional surgery: This is often required because ONJ can present in multiple sites, and in rare cases, may reoccur.

Here’s a rundown of some treatments you can try:

• Pain Relievers: Over-the-counter pain medications like ibuprofen or acetaminophen can help reduce the pain and discomfort associated with osteonecrosis of the jaw.
• Oral Rinses: Antibacterial mouth rinses can help prevent infections in the affected area.
• Nutritional Supplements: Supplements like calcium and vitamin D can support bone health, which is crucial when dealing with osteonecrosis

Prevention

Although frequently associated with dental extractions and bone therapies for cancer treatments, ONJ can also occur without any identifiable precipitating factors. Before beginning a bone therapy regimen, it is important that your physician thoroughly assesses any systemic issues or possible sites of dental infection in order to prevent development of this disease.

Prognosis

This condition can also make eating and drinking very difficult; however, surgery to remove the dead and deteriorating bone can quickly improve circulation and decrease microorganisms.

When to seek further consultation

Call your physician promptly if you note any significant pain in or around your jaw. It does not have to be related to any visible areas of exposed bone.