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Finite element comparison of the effect of absorbers' design in the surrounding bone of dental implants.

牙种植体周围骨吸收器设计效果的有限元比较。

  • 影响因子:2.44
  • DOI:10.1002/cnm.3270
  • 作者列表:"Ashrafi M","Ghalichi F","Mirzakouchaki B","Arruga A","Doblare M
  • 发表时间:2020-01-01
Abstract

:Despite the high success rate achieved in current dental implantation, there are still important problems to solve like incomplete early osteointegration, bone damage, and long-term implant loosening. Highly compliant stress absorbers are a possible solution to these problems. Although several works examined the stress-strain distribution in bone without and with absorbers to show their favorable results, none of them analyzed their impact on long-term remodeling. Here, we analyze this effect by comparing the evolution of stress and bone mass density without and with different designs of absorbers with those of the healthy tooth. Several finite element models with ABAQUS, corresponding to each design considered, were built to obtain the mechanical conditions in bone and implant. Then a mechanobiological bone remodeling model that considers damage accumulation and its repair during the remodeling process was used to compute the bone density redistribution. This approach allows assessing both the short-term density loss and the relative micromovement between bone and implant. We analyze the stress distributions in both bone and implant as well as the relative micromovement of the implant. We also present the evolution of damage and bone volume fraction. These results show that the addition of absorbers can reduce the stress in the bone around the implant. The obtained results also show that using stress absorbers reduces damage in bone, while increasing the number of absorbers does not necessarily improves damage reduction. We conclude that using implants with a correct design of absorbers prevents damage and stress shielding, reducing implant loosening.

摘要

: 尽管目前的种植牙成功率很高,但仍有重要问题需要解决,如早期骨整合不完整、骨损伤和长期种植体松动。高度柔顺的应力吸收器是这些问题的可能解决方案。虽然一些工作检查了没有吸收剂和具有吸收剂的骨中的应力-应变分布以显示其有利的结果,但它们都没有分析它们对长期重塑的影响。在这里,我们通过比较没有和不同设计的吸收剂与健康牙齿的吸收剂的应力和骨密度的演变来分析这种影响。建立了与考虑的每个设计相对应的ABAQUS有限元模型,以获得骨和植入物的力学条件。然后使用在重建过程中考虑损伤积累及其修复的力学生物学骨重建模型来计算骨密度再分配。这种方法允许评估短期密度损失和骨与植入物之间的相对微运动。我们分析了骨和植入物的应力分布以及植入物的相对微运动。我们还介绍了损伤和骨体积分数的演变。这些结果表明,添加吸收剂可以降低植入物周围骨中的应力。所获得的结果还表明,使用应力吸收器减少骨中的损伤,而增加吸收器的数量并不一定改善损伤减少。我们的结论是,使用具有正确设计的吸收剂的植入物可以防止损伤和应力屏蔽,减少植入物松动。

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影响因子:2.98
发表时间:2020-01-01
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