What Is Osteonecrosis of the Jaw?
Osteonecrosis of the jaw, also referred to as ONJ, is a condition where the jaw does not heal, and the bone cells die out, causing jaw pain. There is also a probability of ONJ occurring in individuals on certain medications like bisphosphonates and serious conditions like cancers and bone infections.
As the name is suggestive of this condition, “osteo” means bone, and “necrosis” means death. When the jaw bone is exposed to certain causative risk factors and starts starving because of lack of blood, the bone cells weaken first and then die out, causing pain. This may be only a specific area of the jaw that does not heal (poor healing - for example, as in the case of an extracted tooth socket that does not heal). The area affected by ONJ will not be covered by gums and thus exposed to the oral environment without receiving blood supply.
What Can Cause Osteonecrosis of the Jaw?
Here are some of the factors that are risk-prone for the patient to develop osteonecrosis of the jaw:
1. Trauma or injury to the jaw bone.
2. Radiation therapy to the head and neck.
3. Bone infections.
4. People on bisphosphonate drug therapy.
5. Steroid usage.
6. Poor oral hygiene following extraction.
7. Idiopathic reasons.
What Is a Bone Spur in the Gum?
Bone spur or bone spicule, is defined as entrapment of bony parts or small pieces of bone within the soft tissues of the jaw. This can lead to pain, discomfort, and infection at the site. A bone spur or this bony spicule is medically termed osteonecrosis of the jaw. Necrosis results in dead bone cells and they poke out of the gum tissue. It can occur in either of the jaws and the patient might mistake it for a broken tooth or root. It appears as a bone piece that can be seen easily.
The other causes of a bone spur in the gums are
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Dental injury.
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Tooth extraction.
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Bisphosphonate drugs.
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Radiation and chemotherapy.
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Poor oral health.
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Malnutrition.
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After oral surgeries.
What Are the Risk Factors for Osteonecrosis of the Jaw?
ONJ is caused majorly by these risk factors:
A. Bisphosphonate Related Osteonecrosis of the Jaw (BRONJ)
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Bisphosphonates are drugs that inhibit bone resorption or, in other words, prevent bone cell death. The most commonly used bisphosphonates are Alendronic acid, Risedronate, and Zoledronic acid.
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This is observed in cases where the patient has no previous radiation therapy history but is on bisphosphonate therapy. The conditions in which bisphosphonates are commonly used are:
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In osteoporosis cases (a bone disorder in which the density of bone is affected by becoming weak and brittle).
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In cancer patients and certain bone infections the body requires regular intravenous doses of bisphosphonates.
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To prevent the risk of vertebral and nonvertebral fractures in postmenopausal women with generalized osteoporosis.
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Though bisphosphonates are successfully used in all these conditions, it can reportedly result in ONJ if the patient is undergoing any dental procedure, for which preventive measures can succeed.
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Patients on bisphosphonate therapy are prone to having this condition as they are administered in these diseases and disorders by intravenous route. Oral route bisphosphonate absorption is considered poor.
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Research also indicates that most ONJ cases have occurred in cancer patients with coexisting morbidities like diabetes and infection.
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Management - Though some dental surgeons and physicians are of the opinion that bisphosphonate drug therapy need not be discontinued during or before a dental procedure like tooth extraction, some practitioners advocate stopping the treatment while undergoing dental surgery. In either case, maintenance of oral hygiene holds the key to preventing osteonecrosis of the jaw in patients on bisphosphonate treatment.
B. Osteoradionecrosis of the Jaw
This is a form of ONJ occurring in patients receiving radiation therapy. Most frequently, chemo-radiation therapies destroy the small blood vessels that circulate the blood in the jaw bone. A reduction in these blood vessels will result in a lack of the ability of bone to heal by itself (hypervascularization).
- Management by Dental Surgeon - In cases of osteonecrosis due to radiation, prior to radiation therapy, all undesirable or highly mobile teeth can be removed. Periodontal or gum health can be improved in such cases along with instituting fluoride therapy.
- Management by Physician - Hyperbaric oxygen therapy (HBO) is a common treatment modality for cancer patients, which has proved useful in managing ONJ caused by radiation too. Patients may be advised Penicillin therapy, but the evidence suggests hyperbaric oxygen is much more effective in treatment.
Is Osteonecrosis of the Jaw Fatal?
It is a serious and rare complication observed in patients and can rarely be fatal. Early stages can be treated better with non-surgical treatments. In severe cases, removal of the affected part of the jaw bone is required.
How Is Osteonecrosis of the Jaw Diagnosed, Treated, and Prevented?
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There is no definitive test to detect ONJ, but the presence of the aforementioned risk factors shows the patient would be prone to or may have developed this condition.
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Physicians who treat musculoskeletal disorders like rheumatologists, orthopedics, and endocrinologists are the best advisors on when and how to continue or discontinue the medications prescribed by them before or after a dental procedure.
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The dental surgeon may prescribe oral mouth rinses, analgesics (painkillers), or antibiotics to treat ONJ conservatively. Awareness to visit nearby dentists and maintenance of regular oral hygiene and dental care is a priority in recognizing the symptoms or onset of ONJ.
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Patients should also inform their dentist about the medications they are taking for bone disorders, infections, or cancer treatment (as the drugs used in treating these diseases may be highly potent).
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Another key to preventing ONJ by the dental surgeon is to save teeth with a better prognosis (by root canal treatment) as much as possible in such cases who are prone to this condition. Also, as these individuals at risk are further weakened in immune response, full mouth extractions should be avoided at a stretch.
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Gum surgeries (periodontal surgery) can also be considered of less importance in these individuals, as it can worsen the risk of healing. Dental implants can be carried out in patients with bisphosphonate therapy with antibiotic prophylaxis. Evidence suggests that it would not be risky or have an adverse impact on the jaw.
Conclusion
The risk for osteonecrosis can be reduced by maintaining proper oral hygiene and regular dental care. While going for dental treatment, talk about the medical conditions and medications. Ensure that the medications and dental treatments do not interfere. Regular visits to the dental surgeon and proper oral hygiene and dental care are of pivotal importance in preventing ONJ, especially in the elderly and smoking population. Individuals who are on drug therapies for bone issues can consult the physician before undergoing routine dental procedures or extractions and the dentist can definitely guide the patients by instruction and procedure to prevent the risk of ONJ.
