Medication-related osteonecrosis of the jaw – case report and current therapeutic recommendations

Introduction. Medication-related osteonecrosis of the
jaw – MRONJ is a disease characterised by presence
of denudated bone in facial skeleton inside oral cavity
or though fistulas, persisting for over 8 weeks, during
or following concomitant either antiresorptive or
antiangiogenic therapy, without previous radiotherapy
in head and neck region in anamnesis according
to American Associaton of Oral and Maxillofacial
Surgeons (AAOMS).1 MRONJ is connected with several
groups of drugs: bone metabolism modifying agents
(bisphosphonates – BPs denosumab), antiangiogenic
(sunitynib, bevacizumab) and used in organ
transplantation and oncology (sirolimus, everolimus).
Condition described usually affects patients treated
due to disseminated solid cancers with skeletal
involvement, when above mentioned drugs are applied
to prevent skeletal-related events (SREs). Case report.
Patient described in this paper had been treated with
sunitynib at the beginning of chemotherapy because of
disseminated renal-cell carcinoma with metastases to
lungs and bones, followed with everolimus thereafter.
The event prior to MRONJ occurrence had been teeth
extractions in lateral aspect of the mandible on the
right side. There was antibiotics therapy, conservative
as well as surgical treatment applied in treatment.
Finally, fistula closure was obtained. Discussion.
Exact, complex etiopathogenesis of MRONJ still
remains unclear. Mechanisms of action in each groups
of drugs (inhibiting potential of new blond vessels
growth and wound healing), specifity of facial bones
and existence of MRONJ „triggering event” in most
cases are underlined by many authors.1-6,8,10,13
Conservative treatment based on symptomatic
action and systemic prevention of infection and
surgical debridement in advanced cases are used in
therapy. The role of prophylaxis before introducing
chemotherapy and special procedure protocol in cases
when tooth extrations are necessary are underlined.8
Conclusion. MRONJ is a rare disease, worsening
greatly patients’ comfort of life, which etiology is still
not exactly explained, demanding further study and
adequate animal model.