A patient receiving intravenous zoledronate (Zometa) presents with a molar showing grade 3 mobility, a periodontal probing depth of 5 mm, gingival overgrowth around the crown, and a deep carious lesion. What is the most appropriate management?

Correct answer: B. Endodontic treatment followed by coronectomy, leaving the roots in situ

• A. Alveoloplasty means more bone removal and a larger raw surface — the opposite of what this patient needs.
• B. CORRECT as the strategy. IV zoledronate for oncologic indications carries the highest MRONJ risk of any antiresorptive regimen, and extraction is the single strongest local trigger. Root canal treatment followed by amputation of the crown at the alveolar level — decoronation — eliminates the carious and periodontal focus while leaving the socket and periosteum undisturbed. It is the standard risk-avoidance approach in these patients.
• C. Even an atraumatic extraction with primary closure exposes bone, and in a high-dose IV bisphosphonate patient that is the exposure MRONJ arises from.
• D. Implant placement is contraindicated in patients on high-dose IV antiresorptives for malignancy.

Note: The grade 3 mobility is the complication in this scenario: a tooth that mobile may exfoliate anyway, and endodontics on it is questionable. Discuss with the group. The MRONJ risk tiers are worth memorising — oral bisphosphonates under 4 years carry a very low risk (well under 1%), oral bisphosphonates over 4 years or with concurrent steroids are intermediate, and IV zoledronate or denosumab for cancer runs to several percent.