Background: Osteonecrosis of the jaw (ONJ) is a rare complication, which can be caused by bisphosphonate administration. Clinical features include bone death with areas of persistent bone exposure. This complication can be triggered by several factors including trauma, dental surgery, and infection.

Case Report: The authors report a rare case of ONJ in a 58-year-old female patient, who is on oral ibandronate therapy for osteopenia and subsequent to an episode of herpes zoster (HZ) infection. The patient presented with unresolved gingival swelling with pus exudate and bone exposure at lower right molar area. Tingling sensation was presented at the right side mandibular skin. Root planning was given and followed by Clindamycin administration, however, the condition still persisted. A definitive diagnosis of ONJ was made after no sign of bone healing over a period of 2 months. Ibandronate was then discontinued after consultation with her doctor. Extraction of symptomatic tooth within exposed bone was then considered since periodontal treatment did not improve the condition. Lower right first molar was extracted followed by antibiotic prescription for 2 weeks. The swelling gingiva and exposed bone healed in 2 weeks, the tingling sensation subsided after 4 months, and the extraction socket was completely filled in
3 years.

Conclusion: Long-term oral bisphosphonate administration and an episode of HZ infection could cause ONJ in this patient. HZ
infection may trigger the development of ONJ. This could be due to the impaired healing effect of bisphosphonates.

Keywords: Osteonecrosis of the jaw, Osteopenia, Herpes zoster virus, Bisphosphonate