Medication Related Osteonecrosis of the Jaw (MRONJ), also referred to as Antiresorptive Agent Related Osteonecrosis of the Jaw (ARONJ) and formerly known as Bisphosphonate Related Osteonecrosis of the Jaw (BRONJ), is a rare but intractable disease in humans linked with long term use of potent antiresorptive medications, such as bisphosphonates (BP) and denosumab, and angiogenesis inhibitors. The American Association of Oral and Maxillofacial Surgeons (AAOMS) has preferred the term “medication related osteonecrosis of the jaw” (MRONJ) to include other antiresorptive and antiangiogenic drugs that have also resulted in necrosis of the mandible, maxilla or both. This talk will discuss salient aspects of medication related osteonecrosis of the jaws in cats, specifically bisphosphonate related osteonecrosis of the jaw. Though more commonly published in human literature, this presentation is rare in cats.
Referring to recently published study of 20 cats with MRONJ, learning objectives of this lecture include discussing MRONJ in cats (and humans) and how this disease is thought to occur, and then highlighting presenting concerns, clinical findings, risk factors, diagnoses, interventions, outcomes (including adverse events), and follow-up that can aid in improved prognosis for cats with MRONJ. Given the limited literature in veterinary patients, discussion about MRONJ in humans will be included, where relevant.
The aforementioned case series revealed that cats with feline idiopathic hypercalcemia treated with bisphosphonates (alendronate) may be at a risk for development of MRONJ, a serious oral condition with significant morbidity. Prior dental extraction sites in patients concurrently treated with bisphosphonate medications were often associated with MRONJ lesions. Therefore, any needed dental surgery should be performed prior to the use of bisphosphonates where possible. Diagnosis of MRONJ was made by a correlation of diagnostic findings and patient history. No single diagnostic, or combination was pathognomonic for lesion diagnosis. As well, there were no statistically significant associations between patient variables assessed and the overall patient outcome.
Given the serious morbidity of this disease, and its rarity in the literature, the hope is that this talk will bring light to MRONJ diagnosis and treatments in cats, to ensure appropriate monitoring, client discussion, diligent follow-up and rapid diagnosis and treatment, if a lesion is to ensue.
References
1. Hatunen SL, Anderson JG, Bell CM, Campos HC, Finkelman MD and Shope BH (2024) A retrospective case series on bisphosphonate related osteonecrosis of the jaw in 20 cats. Front. Vet. Sci. 11:1436988. doi: 10.3389/fvets.2024.1436988
2. Ruggiero SL, Dodson TB, Aghaloo T, Carlson ER, Ward BB, Kademani D. American Association of Oral and Maxillofacial Surgeons’ position paper on medication-related osteonecrosis of the jaws-2022 update. J Oral Maxillofac Surg. (2022) 80:920–43. doi: 10.1016/j.joms.2022.02.008
3. Stepaniuk K. Bisphosphonate related osteonecrosis of the jaws: A review. J Vet Dent. (2011) 28:277–81. doi: 10.1177/089875641102800413
4. Yoneda T, Hagino H, Sugimoto T, Ohta H, Takahashi S, Soen S, et al.. Antiresorptive agent-related osteonecrosis of the jaw: position paper 2017 of the Japanese allied committee on osteonecrosis of the jaw. J Bone Min Metab. (2017) 35:6–19. doi: 10.1007/ s00774-016-0810-7
Brief Bio (Submitting and presenting author):
Suzanna Hatunen is a Board Certified Veterinary Dentist™ and Diplomate of the America Veterinary Dental College. She has worked at Veterinary Dental Services since 2021, in Massachusetts, USA. She completed her Bachelor of Veterinary Medicine at the University of Sydney (Australia) in 2017. She then completed a Shelter Medicine and Surgery Internship at the Royal Society for the Prevention of Cruelty to Animals (RSPCA) in 2018, followed by a small animal rotating internship at the University of Sydney, School of Veterinary Medicine in 2019. She is currently undertaking the Thomas P. Sollecito One-Health Oral Medicine Fellowship, through the University of Pennsylvania Dental School
