Faculty of Dentistry, Thammasat University, Pathumthani 12120, Thailand.
Department of Orthodontics, Faculty of Dentistry, Thammasat University, Pathumthani 12120, Thailand; Thammasat University Research Unit in Dental Biomechanics, Thammasat University, Pathumthani 12120, Thailand.
Med Eng Phys. 2022 Sep;107:103872. doi: 10.1016/j.medengphy.2022.103872. Epub 2022 Aug 6.
This study investigated the effects of miniscrew location on biomechanical performance of bone-borne rapid palatal expander (B-RPE) to midpalatal suture, using finite element (FE). Three cases of B-RPE with different miniscrew locations (3 and 6 mm from midpalatal suture and palatal interdental site) were simulated activations in partly ossified midpalatal suture maturation. This study compared the expansion amount and pattern along the suture line. Equivalent von Mises (EQV) stresses at appliance, miniscrew, midpalatal sutures, and elastic strain at the bone around miniscrew were evaluated. In all cases, they could not break the midpalatal suture of palatine bone. However, midpalatal suture at the maxilla was expanded. The expansion amount and unparallel expanding pattern were increased when miniscrews were positioned away from the suture. The interdental miniscrew position extended the suture more than the other 2 cases, but the pattern was unparallel. When the miniscrews were positioned away from the suture, the EQV stress at the appliance and elastic strain at the bone around the miniscrew were reduced. In the case of the palatal interdental miniscrew, all parameters were of lower magnitude. All cases could expand the partly ossified midpalatal suture maturation. The distance between the midpalatal suture and the miniscrew influenced appliance EQV stress, elastic strain at the bone around the miniscrew, and expansion characteristics.
本研究采用有限元（FE）方法探讨微型螺钉位置对骨支式快速腭扩张器（B-RPE）对骨间腭中缝的生物力学性能的影响。模拟了三种不同微型螺钉位置（从中缝 3 和 6mm 以及腭牙间隙）的 B-RPE 部分骨化中缝成熟时的激活情况。本研究比较了沿缝的扩展量和模式。评估了矫治器、微型螺钉、腭中缝和微型螺钉周围骨的等效 von Mises（EQV）应力以及弹性应变。在所有情况下，它们都不能使腭骨的腭中缝断裂。然而，上颌的腭中缝被扩张。当微型螺钉远离缝时，扩展量和非平行扩展模式增加。牙间微型螺钉位置比其他两种情况使缝扩展得更多，但模式是非平行的。当微型螺钉远离缝时，矫治器的 EQV 应力和微型螺钉周围骨的弹性应变减小。在腭牙间微型螺钉的情况下，所有参数的幅度都较低。所有情况都可以扩展部分骨化的腭中缝成熟。腭中缝和微型螺钉之间的距离影响矫治器的 EQV 应力、微型螺钉周围骨的弹性应变和扩展特性。
