Orthodontic treatment as triggering factor of Medication Related Osteonecrosis of the Jaw in a breast cancer patient. Report of a rare case

BACKGROUND: Orthodontic treatment in adult patient is widely accepted nowadays. Therefore, orthodontists are needed to interact with more complex medical histories that may interfere with the orthodontic treatment. Antiresorptive medication is a widely used treatment for osteoporosis or malignancies that may affect the orthodontic movement and planning. CASE PRESENTATION: A 53-year-old patient diagnosed with MRONJ one year after she started orthodontic treatment. Patients’ medical history includes breast cancer and treatment with high doses of denosumab for over 2 years. The patient had a drug holiday period in the start of orthodontic treatment and then resumed antiresorptive medication until extreme tooth mobility was observed during the orthodontic treatment. After a long absence from denosumab and failure of conservative means to control the established MRONJ we proceeded in surgical management of the affected area. After two relapse the patient is now stable and prosthetically rehabilitated. DISCUSSION: The affected area was the only one treated orthodontically and in lack of other triggering factors such as extraction or acute inflammation we consider the orthodontic movement as triggering factor of MRONJ. BPs are widely known to affect orthodontic treatment as they suppress bone remodeling but there is a lack of literature as far as patients treated with denosumab or high doses of antiresorptive medication concern. CONCLUSIONS: Patients treated with high doses of antiresorptive medication should considered at high risk of developing MRONJ during orthodontic movement. Although, more studies are needed to establish a protocol for the patients seeking orthodontic treatment and treated with denosumab. Key words:Medication Related Osteonecrosis of the Jaw, MRONJ, orthodontic treatment, bisphosphonates, denosumab, antiresorptive medication, surgical management.