Ruggiero et al. developed the current clinical staging and treatment strategies for medication-related osteonecrosis of the jaw [3]. Given the presence of pain and erythema in the right mandibular area and exposed necrotic bone associated with infection at the initial stage, our patient was classified as stage 2. Based on the treatment strategies, our patient was treated with systematic antibiotics, incisional drainage, debridement of the abscess, surgical management including removal of the exposed and necrotic bone, and analgesic administration. However, she had persistent severe pain that prevented her from eating and resulted in weight loss, prompting the need for immediate pain relief.

Recent evidence suggests that surgery, including the removal of necrotic bones, can effectively reduce, and ultimately resolve, the pain associated with osteonecrosis of the jaw [2]. However, if the pain has a neurogenic etiology, symptoms may persist Conservative medications are commonly used; non-steroidal anti-inflammatory drugs and acetaminophen for nociceptive pain due to necrosis or infection, pregabalin, mirogabalin, selective serotonin reuptake inhibitors, and weak-to-strong opioids for pain due to neuralgia components [4]. Our patient was refractory to conservative medications and experienced serious adverse effects.

There have been few reports on nonsurgical interventions, other than medication, for pain associated with medication-related osteonecrosis of the jaw. However, neurolysis to the target nerve is occasionally considered effective for chronic neuropathic pain treatment. A previous case report showed that RFT of the Gasserian ganglion improved the quality of life of a patient with medication-related osteonecrosis of the jaw who had terminal cancer [5]. In another report, continuous local anesthetic administration via a catheter near the mandibular nerve has been applied in a patient with medication-related osteonecrosis of the jaw [6]. As for trigeminal neuralgia, RFT is an effective, safe, and minimally invasive neurolysis treatment [7]. Lin et al. performed mandibular nerve block using RFT at 90 °C for 120 s in 104 patients with trigeminal neuralgia and reported a 2-year pain recurrence rate of 8.41% [8]. In our patient, there was no pain recurrence for 3 years, with no complications other than hypoesthesia immediately after the procedure. The improvement in nutritional status due to the ability to eat food and reliable debridement treatment may have contributed to further improvement in her pain. Although RFT causes numbness, which should be explained to the patients for informed consent, other complications are considered less common. Although there are other alternative methods, including surgical neurotomy, minimally invasive RFT should be attempted prior to these methods.

There are currently no clinical studies investigating the efficacy of RFT and the optimal temperature for managing the pain associated with osteonecrosis of the jaw. However, Tun et al. performed ultrastructural evaluation in rat sciatic nerves treated with RF at 42 °C and reported that nearly one-third of the myelinated axons had severe degeneration, although the degree of the ultrastructural grade was better than in the 70 °C group [9]. Furthermore, Smith et al., in a preclinical study, stated that nerve destruction via RF current occurred at temperatures ranging from 45 to 85 °C, suggesting that effective outcomes could be achieved even at lower temperatures. [10] A previous clinical report on trigeminal neuralgia suggested that RFT at lower temperatures was associated with reduced risk of complications such as numbness and masticatory atonia, while still achieving comparable efficacy to RFT at high temperatures [11]. However, there remains no consensus regarding the optimal temperature. Therefore, future randomized controlled trials are warranted to elucidate the utility and indications of RFT.

In conclusion, we report a case of successful RFT of the mandibular nerve for pain caused by medication-related osteonecrosis of the jaw, with no symptom recurrence for 3 years. Minimally invasive RFT may have long-term effects in patients with chronic pain induced by medication-related osteonecrosis of the jaw that is refractory to conservative treatment.