BISPHOSPHONATE-RELATED OSTEONECROSIS OF THE JAW (BRONJ)

In 2003 and 2004 Oral and Maxillofacial Surgeons were the first clinicians to recognize and report cases of non-healing exposed bone in the maxillofacial region in patients treated with IV bisphosphonates.  This finding was followed by a broader drug class warning for this complication in all bisphosphonates, including oral preparations.

Patients may be considered to have Bisphosphonate-Related Osteonecrosis of the Jaw (BRONJ) if all of the following three characteristics are present:

1.  Current or previous treatment with bisphosphonate medication

2.  Exposed bone in the maxillofacial region that has persisted for more than 8 weeks

3.  No history of radiation to the jaws

Patients under treatment with oral bisphosphonate therapy are at a lower risk for BRONJ than patients treated with IV bisphosphonates.  However, reliable incidence data of BRONJ in the oral bisphosphonate patient population is lacking.  In general, these oral bisphosphonate patients have a less severe manifestation of BRONJ and respond more readily to conservative therapy.

If BRONJ is suspected, panoramic and other radiographic imaging may be performed.  However, radiographic changes are not evident until there is significant bone involvement.  A thorough history and intraoral examination is the most effective way to establish the diagnosis.

The goals of therapy in patients with established BRONJ are to eliminate pain and infection as well as minimize the progression of necrosis.  Most patients with limited areas of exposed bone that are asymptomatic can be managed with irrigations alone and close follow-up.  Patients with symptomatic areas of exposed bone that are infected will require oral antibiotic rinses and oral antibiotic therapy for pain relief and infection control.  Areas of necrotic bone that are a constant source of soft tissue irritation should be removed without further bone exposure.  Symptomatic patients with large areas of infected necrotic bone or with pathologic features require surgical resection.

Discontinuation of IV bisphosphonates offers no short-term benefit in BRONJ patients.  However, discontinuation of oral bisphosphonate therapy in patients with BRONJ has been associated with gradual improvement in the clinical disease following adequate treatment. 

Although the pathogenesis of this osteonecrosis process remains to be fully elucidated, it appears that bisphosphonate therapy is closely associated with this complication.  Further research is clearly required to establish the precise relationship between bisphosphonates and osteonecrosis, as well as to more accurately identify those patients at higher risk.

Gary E. Borden, D.D.S., M.S.
Reference: AAOMS Surgical Update
 
Next Issue: April 2010