Examination of the effect between frontal/lateral mandibular translations and masticatory movement on the long-term prognosis of the CAD/CAM crown

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K19130
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 57050:Prosthodontics-related
• Research Institution: The University of Tokushima
• Principal Investigator: OKAWA Toshinori 徳島大学, 大学院医歯薬学研究部(歯学域), 助教 (40726006)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: CAD/CAM冠 / Digital Dentistry / 顎運動 / 咬合面形態

Outline of Final Research Achievements

While the clinical adaptation of CAD / CAM crowns has been expanding, reports of several problems with debonding and fracture with them have been increasing. Therefore, it was hypothesized that these problems were caused by insufficient occlusal adjustment.
The aim of study was clarified where the part of occlusal surface has how much interference from the difference between the gliding movement and the masticatory movement, and was to improve the long-term prognosis of CAD / CAM crowns.
As a result, it was clarified that there is a difference in the pathways of gliding and masticatory movements on the occlusal surface. And it was clarified the amount of interference on both the working side and the balancing side by the non-habitual side mastication tended to be larger than that on the habitual side mastication. In particular, it was clarified that the lingual intracusp slope (C region) on the balancing side tends to interfere.

Free Research Field

歯科補綴学

Academic Significance and Societal Importance of the Research Achievements

昨今の本邦における医療政策を鑑みると，CAD/CAM冠の臨床適応の拡大および長期予後の向上は重要である．また，歯科デジタル技術の発達は著しく，従来法では再現できなかった咀嚼運動も設計に取り入れることが可能となっている．
本研究で得られた結果から，CAD/CAM冠を含む補綴装置の設計時および咬合調整時に注意すべき箇所があることが明らかとなった．また，顎運動に調和した咬合面形態を付与するうえでのデジタル技術使用方法の礎となり得ること，咬合調整にあたり，非習慣性咀嚼側での咬合を特に考慮する必要が明らかになったことについて，初めて定量的な評価ができた点で大きな学術的意義を有していると思われる．