T. I. Tanaka, C. D. Taylor / Case Reports in Clinical Medicine 2 (201 3) 535-537
Copyright © 2013 SciRes. OPEN ACCESS
537
observation. We believe that prolonged bone exposure
was related to her diabetes condition.
It is noteworthy that our patient is taking Letrozole.
Letrozole is an aromatase inhibitor used inthe treatment
of hormonally-responsive breast cancer following sur-
gery. Letrozole has antiandrogen effects and is a poten-
tial inhibitor of epithelial growth factor [10]. Although
the exact etiology of BRONJ remains unclear, over sup-
pression of bone turnover, inhibited angiogenesis and
direct damage to oral mucosa have been considered to
play important roles particularly with ZOL [11]. Letroni-
dazole could further compromise the vasculature and
oxygen perfusion in the jaw bone exacerbating the ad-
verse effects of ZOL.
Due to unpredictable healing outcomes in patients who
developed BRONJ, the treatment is generally conserva-
tive. Invasive treatment such as surgical local debride-
ment of the affected area is usually reserved for severe
cases. Depending on the extent of infection, systemic
antibiotics such as penicillin VK or amoxicillin and/or
topical antibacterial oral suspension may be prescribed.
Infection was localized in our patient case, therefore, the
management was focused on maintenance of optimal oral
hygiene and control of her diabetes. The concept of drug
holidays in an attempt to reduce the risk of ONJ for pa-
tients planned for dento-alveolar surgery is controver-
sial [8,12]. Our patient had the third infusion of 5 mg
ZOL three months after complete healing of her oral le-
sions. The comprehensive dental treatment plan was
modified as a precautionary measure.
4. CONCLUSION
BRONJ as a disease process has multiple contributing
risk factors. Although reported to be low, the incidence
of BRONJ in osteopenic patients taking the once-yearly
infusion of 5 mg ZOL may be higher than previously
thought, especially in those with multiple comorbidities.
Coordinated efforts between physician and oral health
care provider related to the risks and benefits of continu-
ing antiresorptive therapy are imperative. All health care
providers are encouraged to keep abreast of new devel-
opments in this field, assess the risk carefully and inform
patients appropriately.
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