CAJ | 학술논문

目的：采用三维有限元法，比较分析一体化计算机辅助设计与制作（ computer aided design and computer aided manufacture ， CAD／CAM）氧化锆桩核修复的生物力学特点。方法：采用几何的方法分别构建一体化CAD／CAM氧化锆桩核（第1组）、预成氧化锆桩铸瓷核（第2组）、金合金桩核（第3组）上中切牙修复的三维有限元模型，分别通过牙轴与切缘垂直方向和与牙体长轴45°角斜下方向100 N加载，模拟上、下切牙相对时和下颌前伸运动时的两种受力情况。结果：垂直静加载下，无牙本质肩领设计，一体化CAD／CAM氧化锆桩核组牙根的最大Von-Mises应力值最小（11．02 N），预成氧化锆桩组最大（13．17 N），应力分布从切端向根方逐渐递减。2．0 mm高牙本质肩领存在时，桩核及牙根的最大Von-Mises应力值均减小。45°斜向静加载下，在无肩领设计时，一体化CAD／CAM氧化锆桩核的最大Von-Mises应力值最大（20．45 N），金合金桩核的值最小（13．61 N）。2．0 mm高牙本质肩台存在时，牙根的应力值均有减小的趋势，金合金桩核修复组牙根最大Von-Mises应力值最大（14．10 N），一体化CAD／CAM氧化锆桩核修复组牙根应力最小（13．38 N）。结论：通过三维有限元分析推测：相同根管直径的一体化CAD／CAM氧化锆桩核相比预成氧化锆全瓷桩铸瓷核和金合金桩核能更好地分担垂直和侧向的咬合力，并且能够降低牙根的应力分布，起到保护基牙，维护修复体完整性的作用。
목적：채용삼유유한원법，비교분석일체화계산궤보조설계여제작（ computer aided design and computer aided manufacture ， CAD／CAM）양화고장핵수복적생물역학특점。방법：채용궤하적방법분별구건일체화CAD／CAM양화고장핵（제1조）、예성양화고장주자핵（제2조）、금합금장핵（제3조）상중절아수복적삼유유한원모형，분별통과아축여절연수직방향화여아체장축45°각사하방향100 N가재，모의상、하절아상대시화하합전신운동시적량충수력정황。결과：수직정가재하，무아본질견령설계，일체화CAD／CAM양화고장핵조아근적최대Von-Mises응력치최소（11．02 N），예성양화고장조최대（13．17 N），응력분포종절단향근방축점체감。2．0 mm고아본질견령존재시，장핵급아근적최대Von-Mises응력치균감소。45°사향정가재하，재무견령설계시，일체화CAD／CAM양화고장핵적최대Von-Mises응력치최대（20．45 N），금합금장핵적치최소（13．61 N）。2．0 mm고아본질견태존재시，아근적응력치균유감소적추세，금합금장핵수복조아근최대Von-Mises응력치최대（14．10 N），일체화CAD／CAM양화고장핵수복조아근응력최소（13．38 N）。결론：통과삼유유한원분석추측：상동근관직경적일체화CAD／CAM양화고장핵상비예성양화고전자장주자핵화금합금장핵능경호지분담수직화측향적교합력，병차능구강저아근적응력분포，기도보호기아，유호수복체완정성적작용。
Objective:To analyze the biomechanics trait of one-piece computer aided design and com-puter aided manufacture ( CAD/CAM ) zirconia post and core by the three-dimensional finite element . Methods:The three-dimensional finite element models of three upper central incisors restored with one -piece CAD/CAM zirconia post and core ( group 1 ) , refabricated zirconia post and hot-pressed porcelain core ( group 2 ) , and cast gold alloy post and core ( group 3 ) were built by geometry method respectively . 100 N vertical loading through the central incisor models long axis and 100 N loading along directing at an angle of 45°with the models long axis were used to imitate the central incisor stress state in biting and mandible physiological protraction movement .Results:Under vertical loading , the restored teeth without dentin ferrule, the maximum Von-Mises stress value of the tooth root in group 1 was the least(11.02 N), which was the largest (13.17 N)in group 2.The stress became weaker from the upper to the lower of the tooth root.The maximum Von-Mises stress value of the tooth root , post and core became smaller while the restored teeth with the 2.0 mm high dentin ferrule.Under directing at an angle of 45°loading, without the design of dentin ferrule in the restored teeth , the maximum Von-Mises stress value of the post and core in group 1 was the greatest(20.45 N), while that stress of post and core in group 3 was the smallest (13.61 N).With 2.0 mm high dentin ferrule design in the restored teeth , the tooth root stress became weaker.The maximum Von-Mises stress value of the tooth root was the greatest (14.10 N) in group 3, but which was the lowest (13.38 N) in group 1.Conclusion:The results of the three-dimensional finite element analysis infers that one-piece zirconia post and core restoration is more beneficial to disperse the bite force than the prefabricated zirconia post and the cast gold alloy post and core .The one-piece of zirconia post and core is good to protect the teeth and keep the restoration intact .