Effect of inadequate fits of superstructures on surrounding tissue

上部结构不合适对周围组织的影响

• 批准号: 09672004
• 负责人: YAMAMORI Tetsuo
• 金额: $ 2.05万
• 依托单位: Ohu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09672004/
• 关键词: Dental implant; Superstructure; Fit

Bilateral mandibular fourth premolars and first molars from 2 beagle dogs were extracted, and 3 fixtures for each site were inserted 3 months later. Abutments were connected on each fixture 4 months after insertion of the fixture, followed by impression taking. A connected superstructure was set on 3 abutments in each side of mandible and gold screws were tightened with a torque of 10 Ncm. Superstructures were passively fit to the abutments expect for the middle ones of the experimental side, which were given vertical clearance of about 140〜200 μ m between the superstructures and abutments.The tissue blocks including the implants sampled after 5 or 14-week observation were used for the histological examination. Histological findings from both the fit and the misfit groups resembled to each other, and large percentage of the fixture surface directly faced to the bone tissue. In both fit and misfit groups, standardized rentogenographs showed no obvious change in the bone height around the fixtures.For the finite element analysis, the simplified model was created at first. Then the model with reference to the bucco-lingual section of the tissue blocks was made.

拔除2只Beagle犬双侧下颌第四前磨牙和第一磨牙，3个月后每个部位植入3个固定器。插入固定器 4 个月后，将基台连接到每个固定器上，然后进行取模。在下颌骨每侧的 3 个基台上设置连接的上部结构，并以 10 Ncm 的扭矩拧紧金螺钉。上部结构与基台被动贴合，实验侧中部除外，上部结构与基台之间留有约140〜200μm的垂直间隙。观察5或14周后取样的包括种植体在内的组织块用于组织学检查。配合组和不配合组的组织学结果彼此相似，并且固定器表面的很大一部分直接面向骨组织。在拟合组和不拟合组中，标准化的足底图显示固定器周围的骨高度没有明显变化。为了进行有限元分析，首先创建了简化模型。然后参考组织块的颊舌切片制作模型。