Yao Kuang-Ta, Kao Hung-Chan, Cheng Cheng-Kung, Fang Hsu-Wei, Huang Chang-Hung, Hsu Ming-Lun
Department of Dentistry, National Yang-Ming University, Taipei, Taiwan.
Department of Biomedical Engineering, Orthopaedic Device Research Center, National Yang-Ming University, Taipei, Taiwan.
Clin Implant Dent Relat Res. 2015 Dec;17(6):1208-16. doi: 10.1111/cid.12219. Epub 2014 Mar 28.
Conical implant-abutment connections are popular because of good antibending performance. However, the cross section is round, and the antirotational ability is questionable because restorations in the oral cavity also have to bear torsional moments resulting from chewing patterns.
The purpose of this study was to investigate the antirotational ability of conical implant-abutment connections with and without an index.
Conical connection implant system (Cowell Medi, Busan, South Korea) was selected. Two kinds of cyclic loading, a bending moment with (C) and without (L) a torsional moment, were respectively applied to two kinds of abutments, pure cone (N-Octa) and cone with an octagonal index (Octa). The number of cycles to fatigue and the failure modes was recorded. Morphologies of the abutments were examined with scanning electron microscopy.
Only group C(N-Octa) passed the fatigue test, whereas the other three groups failed because of different failure modes. In group L(N-Octa), all abutments generated rotation within 150 cycles. In groups C(Octa) and L(Octa), all abutments fractured but in different areas.
In Cowell implant system (taper angle = 7°), there was no antirotational ability in purely conical connections. Adding an octagonal index could provide an antirotational function but could compromise the antibending strength of the abutment.
锥形种植体-基台连接因其良好的抗弯曲性能而广受欢迎。然而，其横截面为圆形，由于口腔修复体还必须承受咀嚼模式产生的扭矩，其抗旋转能力存在疑问。
本研究的目的是调查有无定位指标的锥形种植体-基台连接的抗旋转能力。
选用锥形连接种植体系统（韩国釜山Cowell Medi公司）。分别对两种基台，即纯锥形（N-Octa）和带八角形定位指标的锥形（Octa），施加两种循环载荷，一种是带有（C）和不带有（L）扭矩的弯矩。记录疲劳循环次数和失效模式。用扫描电子显微镜检查基台的形态。
只有C组（N-Octa）通过了疲劳测试，而其他三组因不同的失效模式而失败。在L组（N-Octa）中，所有基台在150次循环内均发生旋转。在C组（Octa）和L组（Octa）中，所有基台均发生断裂，但断裂部位不同。
在Cowell种植体系统（锥角 = 7°）中，纯锥形连接没有抗旋转能力。添加八角形定位指标可提供抗旋转功能，但会损害基台的抗弯曲强度。
