Morphological mismatch of denture bearing mucosa recorded by optical impression in comparison with the conventional impression

• Project/Area Number: 17K11741
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: Ryunosuke Kazama 東京医科歯科大学, 歯学部, 非常勤講師 (50387429)
• Co-Investigator(Kenkyū-buntansha): 若林 則幸 東京医科歯科大学, 大学院医歯学総合研究科, 教授 (00270918) ; 新井 祐貴 東京医科歯科大学, 大学院医歯学総合研究科, 助教 (70778654)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2019: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2017: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
• Keywords: 有床義歯 / 光学印象 / デジタルデンティストリー / 歯学 / 有床義歯学 / 粘膜厚さ / 口腔内スキャナー / 補綴・理工系歯学

Outline of Final Research Achievements

In order to promote digitalization in the fabrication of dentures, it is necessary to clarify the difference between the shape of the alveolar ridge taken by optical impression and conventional impression. Therefore, our purposes were to clarify the accuracy of the optical impression of the alveolar ridge in the missing teeth model and the actual deviation between the conventional impression and the optical impression. As the result of the deviation analysis of the distal extension missing of the mandibular jaw, the deviation in the overlay image was recognized depending on bilateral/unilateral distal extension missing and the number of missing teeth. Therefore, it was suggested that the optical impression method is influenced by the position of the defect and the number of missing teeth compared with the conventional impression method.

Academic Significance and Societal Importance of the Research Achievements

日本における欠損歯数は減少傾向にあるものの，高齢者の欠損補綴に有床義歯を選択することは多い．材料の削減や印象材の不快感誤嚥・誤飲を回避するためにも光学印象法は大きなメリットを有し，近年急速に進展してきている．一方で，有床義歯への使用にはまだまだ課題が多い．本研究成果により，顎堤粘膜部における光学印象採得の知見が得られたことで今後の有床義歯への光学印象の臨床応用が進展すると考えられる．

Research Products

• [Journal Article] Accuracy of cone beam computed tomography in evaluation of palatal mucosa thickness. (2020)
  • Author(s): Ogawa M, Katagiri S, Koyanagi T, Maekawa S, Shiba T, Ohsugi Y, Takeuchi Y, Ikawa T, Takeuchi S, Sekiuchi T, Arai Y, Kazama R, Wakabayashi N, Izumi Y, Iwata T.
  • Journal Title: J Clin Periodontol. Volume: 4 Issue: 4 Pages: 479-488
  • DOI: 10.1111/jcpe.13254
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Trueness and precision of digital impressions obtained using an intraoral scanner with different head size in the partially edentulous mandible (2018)
  • Author(s): Hayama Hironari、Fueki Kenji、Wadachi Juro、Wakabayashi Noriyuki
  • Journal Title: Journal of Prosthodontic Research Volume: 62 Issue: 3 Pages: 347-352
  • DOI: 10.1016/j.jpor.2018.01.003
  • NAID: 130007458284
  • ISSN: 1883-1958, 1883-9207
  • Peer Reviewed
• [Presentation] 歯科用エックス線CT装置(CBCT)を応用した口蓋粘膜厚径の計測 (2018)
  • Author(s): 小川 実穂, 片桐 さやか, 竹内 康雄, 小柳 達郎, 井川 貴博, 竹内 祥吾, 関内 孝侑, 新井 祐貴, 風間 龍之輔, 若林 則幸, 和泉 雄一
  • Organizer: 日本歯周病学会
• [Presentation] 口腔内スキャナを用いた下顎部分歯列欠損模型における光学印象の真度 (2017)
  • Author(s): 葉山 博工, 笛木 賢治, 和達 重郎, 若林 則幸
  • Organizer: 日本補綴歯科学会東京支部総会・学術大会