Bad to the bone
Identification, management and prevention of BRONJ.
by David A. Salmassy, DMD
PART 2
DIAGNOSTIC TESTING
Managing the condition
Do any of your patients take bisphosphonates? Do you know how to address its risks and impact on the oral cavity? You do now.
Last month, we began our look at the impact of bisphosphonates on the oral cavity. We covered the history of the drug category; warning signs for the oral effects, including bisphosphonate-related osteonecrotic lesions of the jaw (BRONJ); stages of BRONJ; and were made aware of other key risk factors. In this installment, we go a step further in offering suggestions for how to best diagnose and manage BRONJ.
NUTS AND BOLTS
The breakthrough in prevention as well as management was the identification that the C-terminal telopeptide level in blood was correlated with osteoclastic activity and with clinical healing or response to surgical debridement. The serum test, C-terminal cross-linking telopeptide (CTX), measures an octapeptide fragment of Type I bone collagen that is released into circulation upon osteoclastic bone resorption. tI It haas been demonstrated that a CTX value of 100 pg/mL or less represents a high risk for oral bisphosphonate-induced osteonecrosis; a CTX value between 100 pg/mL and 150 pg/mL a moderate risk, and a CTX value of greater than 150 pg/mL a minimal risk. Based on the CTX levels in the study reported by Dr. Robert E. Marx of the University of Miami School of Medicine (34 with bisphosphonate-induced osteonecrosis of the jaw and more than 100 patients who were on oral bisphosphonates when a surgical procedure was indicated), the following recommendations were made:
Three years or less: Prevention recommendations for patients who are about to start on an oral bisphosphonate or those who have taken one for less than three years.
The accumulation of an oral bisphosphonate in bone is slowed by its minimal gastrointestinal absorption. Thus, during the first three years of bisphosphonate consumption, dental practitioners should strive to achieve optimum dental health. Inflammatory conditions should be eliminated during this period so that the need for oral surgical procedures after three years of drug exposure can be reduced or eliminated. This translates into the initial removal of unsalvageable teeth followed by periodontal therapy and comprehensive restorative and prosthodontic treatment.
Three yeears or more: For prevention in patients who have received an oral bisphosphonate for three years or more and require a periodontal or oral surgical procedure.
For these patients it is advisable to obtain a reference CTX value. If the CTX value is below 150 pg/mL, use of the drug should be discontinued temporarily. Such a suspension, also known as a “drug holiday,” is usually acceptable to the prescribing physician due to studies that have documented the continued control of osteoporosis and prevention of fractures with long-term discontinuation of Fosamax. If the prescribing physician is concerned about progression of the osteoporosis without ongoing drug therapy, nonbisphosphonate alternatives can be suggested. After a four- to six- month drug holiday, another CTX test is advised. If the CTX value remains below 150 pg/mL, then the drug holiday should be extended for another four months. The CTX serum test should then be repeated. The rate of osteoclast recovery as measured by the CTX has been 25 pg/mL per month. In all cases observed, the level of CTX in the blood has recovered to a value in excess of 150 pg/mL in six to nine months.
WHAT'S NEXT?
With common dental procedures, knowledge of bone turnover and CTX blood testing, bisphosphonate-induced osteonecrosis of the jaw can be prevented in most cases. When osteonecrosis is already present, it can be resolved in a straightforward manner. It is incumbent on the general dental practitioner, hygienist, or surgical specialist to adequately evaluate and manage the bisphosphonate patient. Assessment should include a staging and assignment of the risk group for the patient, and then managing the patient within the published guidelines of care. This should also include consultation with the patient’s primary medical care provider or oncologist where staging of the risk and treatment strategies require clarification.
While there is much more to be said in treating patients with BRONJ, the information here can help you take the intial steps necessary in educating your peers and your patients.
Dr. David Salmassy is an Oral and maxillofacial surgeon with a private practice in Auburn, Calif.
photos: jupiterimages
Bone up!
Want to learn more? Check out these resources.
Ruggiero SL, Fantasia J, Carlson E: Bisphosphonate related osteonecrosis of the jaw: Background and guidelines for diagnosis, management and staging. Oral Surg Oral Med Oral Path Oral Rad Endo 102: 433, 2006
AAOMS: American Association of Oral and Maxillofacial Surgeons Position Paper on Bisphosphonate-Related Osteonecrosis of the Jaws. Available at: http://www. aaoms.org/docs/position_papers/ osteonecrosis.pdf
AAOMS Webinar on BRONJ
Ruggiero SL, Mehrotra B, Rosen-berg TJ, et al: Osteonecrosis of the jaws associated with the use of bisphosphonates: A review of 63 cases. J Oral Maxillofac Surg 62: 527, 2004
Marx RE. Oral and Intravenous Bisphosphonate Induced Osteonecrosis of the Jaws: History, Etiology, Prevention, and Treatment. Chicago: Quintessence, 2006:77-95.