Okazaki M
Nihon Hotetsu Shika Gakkai Zasshi. 1989 Oct;33(5):1247-60. doi: 10.2186/jjps.33.1247.
The dispersion of occlusal forces around both the abutment teeth and the alveolar mucosa is generally considered as an most important principal in minimizing the denture mobility and the local over-load on designing the distal extention-type denture. This study was undertaken to investigate the principal factors in designing uni-lateral-type clasp denture equipped with direct and indirect retainer. Our data show: 1. Guide-plane provides maximam retention power in cooperation with high fixable indirect retainer. 2. Direction of load and design of the denture are the major responsible factors for shifting the horizontal rotation center of denture body. Especially the shape of indirect retainer was demonstrated to alter direction and amount of displacement of the denture base and abutment teeth. 3. Most types of uni-lateral distal extention denture exhibited upward and downward movement when they function in vivo. 4. Negative type indirect retainer plased at incisor was shown to be harmful due to its intrinsic slunting force on teeth to labial direction. On the other hand positive type indirect retainer was considered to be more desirable because the force through clasp moves abutment teeth vertically.
在设计远中游离端义齿时，基牙和牙槽黏膜周围牙合力的分散通常被认为是使义齿移动最小化以及局部过载最小化的最重要原则。本研究旨在调查设计有直接和间接固位体的单侧型卡环义齿的主要因素。我们的数据表明：1. 导平面与高固位间接固位体协同作用可提供最大固位力。2. 负荷方向和义齿设计是导致义齿主体水平旋转中心移动的主要因素。特别是间接固位体的形状被证明会改变义齿基托和基牙的位移方向和量。3. 大多数类型的单侧远中游离端义齿在体内发挥功能时表现出上下运动。4. 放置在切牙处的阴性型间接固位体因其对牙齿向唇侧的固有倾斜力而被证明是有害的。另一方面，阳性型间接固位体被认为更可取，因为通过卡环的力使基牙垂直移动。
