【作者】 刘梅；

【导师】 王敏； 林映荷；

【作者基本信息】 四川大学 ， 口腔临床医学， 2004， 硕士

【摘要】 套筒冠义齿是一种临床应用面很广的修复体,对游离端缺失、多数牙缺失、基牙伴牙周病的牙列缺损的修复效果都要优于常规可摘义齿。但是套筒冠制作工艺复杂,制作材料一般又是金合金,这使得套筒冠义齿的修复价格昂贵,很多具有适应症的患者得不到最佳修复。国内外也有关于套筒冠固位体采用非贵金属材料的研究,但都是局限于材料本身的物理、机械与生物性能,没有从口腔这个受力情况复杂的生物力学环境出发进行研究。本研究就是在此基础上提出的,利用三维有限元法对四种不同材料的游离端套筒冠义齿进行位移分析,为临床选用提供一定的理论依据。 实验采用螺旋CT扫描牙列完整、咬合关系正常、无明显牙周疾病、无后牙牙体缺损及明显磨耗的成年男性一例,取得原始数据,用Dicomviewer软件将其转化为BMP格式,自编程序处理读取边缘数据,边缘数据写入ANSYS软件中,舍弃左侧第一、第二磨牙牙根边缘数据,保留冠部边缘数据作为义齿人工牙的(牙合)面,利用机器手工相结合的方式连接边缘点建立单侧下颌模型,AutoCAD中模型修改,建立左侧下颌单侧游离端缺失的圆锥型套筒冠义齿模型。通过ANSYS软件对模型自由划分网格,建立三维有限元模型。修改材料参数建立不同材料(镍铬合金、钴铬合金、钛合金、金合金)的三维有限元模型。用ANSYS软件进行加载后位移分析,比较不同材料的套筒冠义齿受载后基牙牙周组织的位移值。结果显示:四种材料的近远中向位移差别不超过0.001mm,占总位移量的1%;垂直向位移的差别不超过0.005mm,占总位移量不到更多还原

【Abstract】 Telescopic dentures are widely used in clinic, can be used in repairing ditsal extensional teeth default; numerous teeth default, and the teeth default in which the abutments has periodontics. The repairing effect is better than other removable partial dentures. But the technics of telescopic crowns is complex, and materials usually select golden alloy(Ⅲ). All these increase the cost of telescopic dentures, and limit the use field of them. There is much research about the materials of telescopic crowns, but all of them are limited in the physical, mechanical and biomedical properties. There has no study about biomechanical property of these materials. So this study is rised in this situation, the study use the Finite Element Method to analyse the displacement of abutments with different materials, and supply the theory fundamental for clinical use.The study utilize CT to scan the mandible of a healthy man, in order to receive the primal data, and then use software named Dicomviewer to change the primal data into BMP format. The program made by ourselves deal with these picture to get the fringe data, and write these fringe data into ANSYS. Fringe data of first and second molar root will be abandoned, the data of their crown will be preserved to form the occlusal shape of the artificial teeth. Link these fringe data with manual and mechanical methods to get the three-dimensional mode of left mandible. InAutoCAD, amend the mode to set up the left mandible’s three-dimensional mode of telescopic dentures. Divide lattices in ANSYS to set up the three-dimensional finite element mode. Change the parameter of materials and then set up different materials finite element mode (Nickel-chrome alloy, Cobalt-chrome alloy alloy, Titanium, Golden alloy). In ANSYS , we analyse the displacement of the abutments under load, compare the value of abutment’s displacement. Result: the medial-distal abutment displacement difference of four kinds of materials is no more than 0.001 mm, account for 1% of total displacement; the difference of vertical displacement is no more than 0.005 mm, account for 2.5% of total displacement; the difference of buccal-lingual displacement is no more than 0.0001 mm, account for 0.7 % of total displacement.Conclusion: there is no difference between four kinds of telescopic dentures of difference materials, Nickel-chrome alloy, Cobalt-chrome alloy, Titanium and Golden alloy can be used as materials of telescopic dentures according to this biomechanical study.更多还原