Osteonecrosis of the jaw (ONJ) is a condition where a lack of blood supply causes jaw bone tissue to die. The term “early” refers to the initial phases, before significant bone loss or severe symptoms have developed. In its beginning stages, ONJ may not present with dramatic signs, making it a subtle but serious oral health issue requiring timely care.
Identifying Early Signs and Symptoms
The initial presentation of osteonecrosis of the jaw can be subtle and mistaken for common dental problems. Some individuals may first notice unexplained jaw pain or a toothache not connected to decay. Another early indicator is the loosening of teeth without any apparent cause like gum disease or injury.
A noteworthy early symptom is a persistent feeling of numbness or heaviness in the jaw. This sensation can be chronic and may lead a person to constantly feel the need to check or move their jaw. In some cases, slow or poor healing after a dental procedure, such as a tooth extraction, can be a clue that the jawbone’s ability to repair itself is compromised.
In the earliest phase, known as Stage 0, there may be no visible signs of exposed bone. Instead, the symptoms are non-specific, such as jaw pain that could be attributed to other issues. The definitive sign of ONJ is exposed bone in the mouth that does not heal, but this often appears after the initial symptoms.
Key Risk Factors and Causes
The development of ONJ is strongly linked to medications that interfere with bone maintenance. The two main categories are bisphosphonates and anti-angiogenic agents. Bisphosphonates, like Zometa for cancer treatment and Fosamax for osteoporosis, slow the rate at which bone is broken down, which can lead to older bone with a reduced blood supply that is less able to heal.
Anti-angiogenic drugs, such as denosumab (Xgeva for cancer patients and Prolia for osteoporosis), disrupt bone turnover by inhibiting the formation of new blood vessels, a process the body relies on for healing. Patients receiving these drugs intravenously for cancer treatment are at a higher risk than those taking lower oral doses for osteoporosis.
While medications are a primary factor, other conditions and behaviors can increase the risk. Invasive dental procedures, especially tooth extractions, are a precipitating factor, as they create an injury site that may fail to heal. Chronic inflammation from periodontal disease also contributes. Systemic factors such as cancer, diabetes, smoking, and the use of steroids can compound the risk.
The Diagnostic Process
Confirming a diagnosis of early-stage ONJ begins with a clinical examination by a dentist or oral surgeon. The professional will inspect the mouth for any signs of exposed bone and assess for swelling, redness, or discharge. A diagnostic criterion is the persistence of exposed bone for more than eight weeks in a patient with known risk factors.
Imaging studies support the diagnosis, especially in early stages when visible signs may be minimal. Standard dental X-rays, such as panoramic radiographs, might be taken first but may only reveal changes after significant bone damage has occurred. For a more detailed assessment, advanced imaging techniques are often employed.
A cone-beam computed tomography (CBCT) or a standard CT scan can provide a clearer picture of bone involvement. In some cases, Magnetic Resonance Imaging (MRI) may be used because it shows early changes in bone marrow and surrounding soft tissues. These imaging tools help determine the extent of the necrosis and differentiate ONJ from other conditions like osteomyelitis.
Management and Treatment Strategies for Early Stages
The focus of managing early-stage ONJ is conservative, aiming to control symptoms, prevent infection, and halt the progression of bone damage without aggressive interventions. This approach involves maintaining excellent oral hygiene to reduce the bacterial load in the mouth, often supplemented by an antimicrobial mouth rinse, such as chlorhexidine.
When signs of a secondary infection appear, such as pain or swelling, systemic antibiotics are prescribed. Pain management is also a priority, addressed with analgesic medications. Throughout this period, it is important to avoid further invasive dental procedures, like extractions or implants if possible, as this could worsen the condition.
In situations where a small, loose piece of dead bone (a sequestrum) has formed, a sequestrectomy may be performed. This involves the gentle removal of the necrotic bone fragment to smooth any sharp edges irritating the surrounding soft tissues. This can facilitate gum tissue healing over the area and help resolve symptoms.
Preventive Measures
For individuals at risk for ONJ, a comprehensive dental examination and completing any necessary dental work should occur before initiating treatment with high-risk medications. This includes addressing any existing infections, performing extractions of non-restorable teeth, and ensuring overall oral health is stable.
Ideally, there should be a healing period of at least 14 to 21 days after any dental extractions before a patient starts taking these medications. This allows the extraction socket to heal properly. Once on the medication, maintaining meticulous oral hygiene through daily brushing and flossing, along with regular professional dental cleanings, is required.
Patients should always inform their dental professionals that they are taking these specific medications. This knowledge allows the dental team to make informed treatment decisions, such as opting for a root canal to save a tooth rather than extracting it. Immediate communication with both the dentist and the prescribing doctor about any new oral symptoms is important.