摘要
目的:探讨上颌后牙区倾斜植入种植体对种植体-骨界面应力分布的影响,阐明倾斜种植固定桥各影响因素与种植义齿远期成功的相关性。方法:建立上颌后牙区垂直骨量不足的三维有限元模型,设计种植体不同的长度(7、9和11mm,种植体直径5.5mm,倾斜角度10°)、直径(3.5、4.5和5.5mm,种植体长度7mm,倾斜10°)及植入的倾斜角度(5°、10°和15°,种植体直径5.5mm,长度7mm)等实验条件,在集中及分散载荷的作用下对种植体-骨界面的应力分布状况进行分析。结果:应力分布比较:种植体长度以7、9和11mm变化时,种植体颈部及根尖部应力值较大,且根尖区应力大于颈部,随长度增加根尖区应力下降,与颈部接近。不同直径的种植体-骨界面应力分布特征为:在直径为3.5和4.5mm工况下,种植体颈部与根尖部应力值较大;当直径为5.5mm时,种植体-骨界面各部分应力值趋于相等。不同倾斜角度的种植体-骨界面应力分布相似,种植体颈部与根尖部应力值较大。当倾斜角度为5°时,种植体颈部与根尖部应力值相当,当倾斜角度逐渐增大时根尖部应力值相应增大。载荷的分布也影响种植体-骨界面的应力分布,集中载荷作用下的应力峰值高于分散载荷作用下的峰值,而且种植体根尖区应力峰值大于颈部应力峰值。结论:当上颌后牙区骨量相对不足时,采用长度长、直径粗的种植体以小角度倾斜植入可使应力分布更趋分散,同时应充分考虑上颌骨复杂的解剖结构(尤其是前磨牙区颊侧骨壁较薄时),防止局部骨壁过薄,产生应力集中。
Objective To study the influence of incline implant supported fixed bridge at the local area of the maxillary molar on the implant-bone-interface stress distribution and illustrate the correlation between every influence factors about incline implant supported fixed bridge and late success rate of implant denture. Methods Three-dimensional finite element model for the insufficient vertical bone mass at the area of the maxillary molar was established biomechanically in this study by spiral CT technique and finite element software technique. Different experimental conditions were designed which were about different implant lengthes（7,9and 11mm,diameter of implants was 5.5mm and oblique angle was 10°）,implant diameters（3.5,4.5and 5.5mm,length of implants was 7mm and oblique angle was 10°）and oblique angles of implant（5,10and 15°,diameter of implants was 5.5mm,length of implants was 7mm）.The implant-bone-interface stress distribution was analyzed by 3-D finite element method under the action of vertical and decentralized load.Results When implant length changed from 7to 11mm,the stress of necks and root tips of implants was big,and the one on root tips was bigger than the necks at the same time.The stress on root tips was decreased as the length of the implant was increased and was closed to the necks.The feature on stress distribution of different diameters was that the stress of necks and root tips of implants was big with 3.5and 4.5mm in diameter,and the stress on each part of the implant-bone-interface was similar with 5.5mm in diameter.The feature of stress distribution on each part of the implant-bone-interface was very close in resemblance with different oblique angles,the stress of necks and root tips of implants was big. The stress of root tips of implants was increased as the angle was increased.Load distribution also affected stress distribution on the interface.The peak stress under a concentrated load was bigger than the one under decentralized load.Conclusion When the vertical bone mass at the local area of the maxillary molar is relative insufficient,the implant-bone interface stress distribution tends towards uniformity in selecting longer and wider-diameter implant. The complicated maxillary anatomical structure could be considered adequately to prevent stress concentration to occur in partial thick bone.
出处
《吉林大学学报（医学版）》
CAS
CSCD
北大核心
2010年第5期957-961,1004,共6页
Journal of Jilin University：Medicine Edition
基金
吉林省科技厅科研基金资助课题(200705341)
关键词
倾斜种植
上颌后牙区
应力
三维有限元分析
incline implant
local area of maxillary molar
stress
three-dimension finite element analysis
