Miyashita, Hidetaka

写真a

Affiliation

School of Medicine, Department of Dentistry and Oral Surgery (Shinanomachi)

Position

Assistant Professor/Senior Assistant Professor

 

Papers 【 Display / hide

  • Remarkable response of diffuse sclerosing osteomyelitis of the mandible to zoledronate by single infusion without prior treatment of other bisphosphonates

    Yamada M., Iwata S., Nishi K., Ochiai S., Araki D., Soma T., Yamada Y., Miyashita H., Suga K., Asoda S.

    Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology (Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology)  34 ( 6 ) 777 - 783 2022.11

    ISSN  22125558

     View Summary

    Diffuse sclerosing osteomyelitis of the mandible (DSOM) is a nonsuppurative osteomyelitis mainly characterized by recurrent local mandibular swelling and pain. Because of the unknown pathophysiological mechanism underlying DSOM, treatment can be challenging. Reported treatment options include long-term analgesic medication, non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics, corticosteroids, hyperbaric oxygen, and surgical treatment. However, these treatments cannot reliably lead to a long-lasting reduction of complaints. Recently, bisphosphonates has been reported effective in managing DSOM. We herein report a case of DSOM with a favorable response to a single infusion of zoledronate without prior treatment of other bisphosphonates. The patient was a 19-year-old woman who visited our hospital complaining of swelling and remarkable spontaneous pain in the right mandibular angle region. Under the diagnosis of osteomyelitis of the mandible, the clinical symptoms were improved by administering an antimicrobial agent and anti-inflammatory analgesic, but computed tomography (CT) showed exacerbation of bone resorption. A biopsy showed fibrosis between the bone tissue and trabeculae, a finding consistent with post-inflammatory changes. 99mTc scintigraphy showed an abnormal accumulation in the right mandibular ramus. Based on these results, she was diagnosed with DSOM. As a result of discussing with the physician in charge of internal medicine, it became the policy of the bisphosphonates and the intravenous administration of zoledronate 4 mg was enforced. Her bone sclerosis and bone resorption showed an improving trend on CT three months after the zoledronate administration, and there have been no symptoms or exacerbation of findings in three years since the administration.

  • The use of SPECT/CT to assess resorptive activity in mandibular condyles

    Munakata K., Miyashita H., Nakahara T., Shiba H., Sugahara K., Katakura A., Nakagawa T.

    International Journal of Oral and Maxillofacial Surgery (International Journal of Oral and Maxillofacial Surgery)  51 ( 7 ) 942 - 948 2022.07

    ISSN  09015027

     View Summary

    The aim of this study was to clarify the clinical significance of bone metabolism in the mandibular condyles in determining condylar resorptive changes. Twelve condyles of patients with idiopathic condylar resorption and degenerative joint disease were analysed using 99mTc HMDP SPECT/CT at baseline and subsequent computed tomography during the follow-up period. Twenty-two healthy condyles were enrolled as controls. After generating three-dimensional SPECT/CT images, two independent observers scored the degree of condylar uptake and measured the morphological changes in the condylar height and condylar volume. In the group with positive condylar uptake, the follow-up computed tomography showed significant decreases in condylar height (−1.69 ± 0.93 mm) and condylar volume (−12.51 ± 10.30%) when compared to healthy controls (condylar height, 0.09 ± 0.54 mm; condylar volume, −0.29 ± 4.22%) (P < 0.001). Moreover, the degree of uptake correlated with the changes in condylar height (observer 1, P = 0.012; observer 2, P = 0.039) and condylar volume (observer 1, P = 0.005; observer 2, P = 0.037). These results suggest that condylar bone metabolism is closely related to the resorptive activity. Thus, SPECT/CT would be useful in the prognostic evaluation or determination of treatment strategies for idiopathic condylar resorption and degenerative joint disease.

  • Large pyogenic granuloma associated with a dental implant: A case report

    Nagamine H., Yasui T., Kimura M., Karube T., Sato H., Miyashita H., Asoda S., Kogai H., Kawana H., Onizawa K.

    Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology (Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology)  34 ( 3 ) 315 - 321 2022.05

    ISSN  22125558

     View Summary

    Although gingival reactive lesions such as pyogenic granulomas (PG) are fairly common in gingiva with natural teeth, their occurrence in association with dental implants is relatively rare. Additionally, these lesions are relatively small in size (10 mm). This case report presents a large PG observed in association with a dental implant and a systematic review of the literature on implant-associated PG. A 66-year-old woman presented at our department with a smooth, slightly red pedunculated lesion measuring 45 mm × 40 mm × 20 mm on the buccal and lingual gingiva surrounding the left mandibular second molar dental implant. Horizontal alveolar bone loss around the dental implant was observed on panoramic radiographs and cone-beam computed tomography. A biopsy was performed, and a histopathological diagnosis of PG was made. Complete resection of the lesion and curettage of the implant surface under local anesthesia was carried out. The patient exhibited no recurrence of PG after one year of follow-up.

  • Clinical value of entire-circumferential intraoperative frozen section analysis for the complete resection of superficial squamous cell carcinoma of the tongue

    Asoda S., Miyashita H., Soma T., Munakata K., Yamada Y., Yasui Y., Kudo Y., Usuda S., Hasegawa T., Nakagawa T., Kawana H.

    Oral Oncology (Oral Oncology)  123 2021.12

    ISSN  13688375

     View Summary

    Objectives: We aimed to evaluate the clinical value of an entire-circumferential intraoperative frozen section analysis (e-IFSA) for the complete resection of superficial squamous cell carcinoma (SCC) of the tongue. Materials and Methods: A total 276 specimens from 51 patients with pT1-2, N0, mucosal or submucosal invasion SCC were analyzed to evaluate the diagnostic accuracy of the e-IFSA and the added value of the e-IFSA to iodine staining. The e-IFSA results were compared with the final histologic results obtained using permanent sections. All specimens for the e-IFSA were taken over the entire circumference 5 mm outside from the iodine unstained areas. The outline of the main resected specimen after taking these outer mucosal specimens were defined as the surgical margins determined by iodine staining alone. Results: The e-IFSA results were in excellent agreement with final histological results (Cohen's kappa value: 0.85) and the e-IFSA showed high sensitivity (100%) and high negative predictive value (100%). The actual complete resection rate with an e-IFSA was 100% (51/51), and no patient required additional resection after surgery. In contrast, 10/51 patients (20%) patients showed residual atypical mucosal epithelium at or beyond the margin determined by iodine staining alone; this difference was statistically significant (P = 0.002). The 5-year local control rate and 5-year overall survival rate after this procedure were both 100%. Conclusion: An e-IFSA has additional value when performed in conjunction with iodine staining. An e-IFSA would be useful for achieving complete resection of superficial SCC of the tongue.

  • Development of a microsurgery-assisted robot for high-precision thread traction and tension control, and confirmation of its applicability

    Hangai S., Nozaki T., Soma T., Miyashita H., Asoda S., Yazawa M., Sato K., Kawana H., Ohnishi K., Kobayashi E.

    International Journal of Medical Robotics and Computer Assisted Surgery (International Journal of Medical Robotics and Computer Assisted Surgery)  17 ( 2 )  2021.04

    ISSN  14785951

     View Summary

    Background: Microsurgery requires high skills for suturing using fragile threads, often within narrow surgical fields. Precise tension is required for good healing and to avoid the risk of thread breakage. Methods: To meet the demands, we developed a novel assist robot utilizing high-precision sensorless haptic technology. The robot adopts a cable-driven mechanism to maintain a distance from the surgical area and enhances compatibility with surgical equipment such as microscopes. The robot performance was verified through in vitro and in vivo experiments using a rat model. Results: The realization of precise tension control was confirmed in both experiments. In particular, in the in vivo experiments, the developed robot succeeded to produce a knot with an accurate tension of 0.66% error. Conclusions: The developed robot can realize to control traction force precisely. This technology might open up the window for a full assist robot for microsurgery with haptic feeling.

display all >>

Research Projects of Competitive Funds, etc. 【 Display / hide

  • 広範囲顎骨欠損に対するメカノバイオロジー最適化スキャフォールドの開発

    2021.04
    -
    2024.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Early-Career Scientists , Principal investigator

 

Courses Taught 【 Display / hide

  • PATHOPHYSIOLOGICAL ISSUES IN CHRONIC CARE

    2024

  • PATHOPHYSIOLOGICAL ISSUES IN CHRONIC CARE

    2023

  • PATHOPHYSIOLOGICAL ISSUES IN CHRONIC CARE

    2022

  • PATHOPHYSIOLOGICAL ISSUES IN CHRONIC CARE

    2021