Horie Nobuyuki, Ouchi Takehito, Nishiyama Rumiko, Usuda Sho, Morikawa Satoru, Asoda Seiji, Nakagawa Taneaki
Department of Dentistry and Oral Surgery, Keio University School of Medicine.
Bull Tokyo Dent Coll. 2019 Dec 10;60(4):233-239. doi: 10.2209/tdcpublication.2018-0068. Epub 2019 Nov 23.
The need for flexible thermoplastic denture base materials has increased due to patient demand for better esthetic outcomes. Designs aimed at improving esthetic outcomes can cause difficulties for prosthodontists, however, from the viewpoint of function and maintenance. Therefore, the purpose of this study was to investigate vertical displacement in unilateral extension base denture models, comparing that obtained by flexible removable dentures with that by conventional metal clasp dentures. Models of unilateral extension base flexible removable dentures for mandibular defects were prepared. Periodontal ligament and jaw mucosa were simulated using a silicone impression material. Four types of flexible removable denture, with or without a metal rest, and two metal clasp dentures made of acrylic resin as a conventional design were used as dental prostheses. The amount of vertical displacement in the defect areas was measured under a load of 50 N at the first and second molars. Among the 6 types of dentures investigated, the amount of vertical displacement was greater with flexible removable dentures than with metal clasp dentures. This vertical displacement tended to decrease significantly, however, with the use of a metal rest with the flexible removable dentures. Esteshot with a metal rest, in particular, showed the smallest amount of displacement in the flexible removable dentures (first molar, 0.265±0.007 mm; second molar, 0.423±0.008 mm). These results indicate the importance of the application of rests in unilateral extension base flexible removable dentures. It may be useful to employ a metal rest in conjunction with a flexible removable denture to reduce load on the underlying mucosa, as is done with conventional partial dentures.
由于患者对美观效果有更高要求，对柔性热塑性义齿基托材料的需求增加。然而，从功能和维护的角度来看，旨在改善美观效果的设计可能会给口腔修复医生带来困难。因此，本研究的目的是调查单侧伸展基托义齿模型中的垂直位移，比较柔性可摘义齿和传统金属卡环义齿的垂直位移情况。制备了用于下颌缺损的单侧伸展基托柔性可摘义齿模型。使用硅橡胶印模材料模拟牙周膜和颌黏膜。四种带或不带金属支托的柔性可摘义齿，以及两种作为传统设计的由丙烯酸树脂制成的金属卡环义齿被用作假牙。在第一和第二磨牙处以50 N的载荷测量缺损区域的垂直位移量。在所研究的6种义齿中，柔性可摘义齿的垂直位移量比金属卡环义齿大。然而，使用带金属支托的柔性可摘义齿时，这种垂直位移倾向于显著减小。特别是带有金属支托的Esteshot在柔性可摘义齿中显示出最小的位移量（第一磨牙，0.265±0.007 mm；第二磨牙，0.423±0.008 mm）。这些结果表明了在单侧伸展基托柔性可摘义齿中应用支托的重要性。与传统局部义齿一样，在柔性可摘义齿上结合使用金属支托以减轻下方黏膜的负荷可能是有用的。
