论文部分内容阅读
目的:探讨0.018〞澳丝弯制的不同角度后倾曲对下颌第二磨牙作用力的情况。方法:应用CT扫描技术、Auto CAD及ANSYS相结合的建模程序,以中国人正常下颌骨为建模的实体参照,建立下颌第二磨牙及其牙周组织的三维有限元模型,同时建立用0.018〞澳丝弯制附5°、10°、15°、20°、25°、30°六个不同角度磨牙后倾曲唇弓的三维有限元模型,利用弯曲梁应变原理,计算出不同角度后倾曲作用下,下颌第二磨牙颊面管近中端及远中端力的大小及方向。结果:第二磨牙近中受到向伸长力,远中受到龈向压低力,其大小随着角度的增大而增大,近中力值大于远中力值。结论:后倾曲对第二磨牙产生远中倾斜力矩;随着后倾曲角度增大,磨牙呈现远中直立的趋势,同时牙冠舌向倾斜趋势加大。
OBJECTIVE: To investigate the force of 0.018 "Orthodontics at different angles on the second molar of the mandible.Methods: By using the CT scanning technology, Auto CAD and ANSYS combined modeling program, The three-dimensional finite element model of the mandibular second molar and its periodontal tissue was established referring to the modeling entity. At the same time, a three-dimensional finite element model of mandibular second molar with 5 °, 10 °, 15 °, 20 °, 25 °, 30 ° Three-dimensional finite element model of the posterior lip of the mandibular second molar was established by using the three-dimensional finite element model of the posterior lip of the mandibular second molar. The bending force of the bending beam was used to calculate the size and direction of the proximal and distal mid- . Results: The second molars received the extensional force in the proximal direction and the gingival downward force in the distal direction. The size of the second molars increased with the increase of the angle, and the near-mid-strength value was greater than the far-mid-force value. CONCLUSION: Posterior tilt has a far mid-tilt moment on the second molars. With the increase of posterior tilt angle, the molars show a tendency of getting upright in the middle and the inclination of the tongue crowns increases.