Seong Eui-Hyang, Choi Sung-Hwan, Kim Hee-Jin, Yu Hyung-Seog, Park Young-Chel, Lee Kee-Joon
Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea.
Institute of Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea.
Korean J Orthod. 2018 Mar;48(2):81-89. doi: 10.4041/kjod.2018.48.2.81. Epub 2018 Feb 6.
The aim of this study was to evaluate the stress distribution and displacement of various craniofacial structures after nonsurgical rapid palatal expansion (RPE) with conventional (C-RPE), bone-borne (B-RPE), and miniscrew-assisted (MARPE) expanders for young adults using three-dimensional finite element analysis (3D FEA).
Conventional, bone-borne, and miniscrew-assisted palatal expanders were designed to simulate expansion in a 3D FE model created from a 20-year-old human dry skull. Stress distribution and the displacement pattern for each circumaxillary suture and anchor tooth were calculated.
The results showed that C-RPE induced the greatest stress along the frontal process of the maxilla and around the anchor teeth, followed by the suture area, whereas B-RPE generated the greatest stress around the miniscrew, although the area was limited within the suture. Compared with the other appliances, MARPE caused relatively even stress distribution, decreased the stress on the buccal plate of the anchor teeth, and reduced tipping of the anchor teeth.
The findings of this study suggest that the incorporation of miniscrews in RPE devices may contribute to force delivery to the sutures and a decrease in excessive stress on the buccal plate. Thus, MARPE may serve as an effective modality for the nonsurgical treatment of transverse maxillary deficiency in young adults.
本研究的目的是使用三维有限元分析(3D FEA)评估在年轻成人中使用传统(C-RPE)、骨支抗(B-RPE)和微螺钉辅助(MARPE)扩弓器进行非手术快速腭扩展(RPE)后各种颅面结构的应力分布和位移。
设计传统、骨支抗和微螺钉辅助腭扩弓器,以模拟在从一名20岁人类干燥颅骨创建的三维有限元模型中的扩展。计算每个上颌骨周围缝和支抗牙的应力分布和位移模式。
结果表明,C-RPE在上颌骨额突和支抗牙周围诱导出最大应力,其次是缝合区域,而B-RPE在微螺钉周围产生最大应力,尽管该区域局限于缝合线内。与其他矫治器相比,MARPE导致相对均匀的应力分布,降低了支抗牙颊板上的应力,并减少了支抗牙的倾斜。
本研究结果表明,在RPE装置中加入微螺钉可能有助于将力传递到缝合并减少颊板上的过度应力。因此,MARPE可能是年轻成人横向上颌骨发育不全非手术治疗的一种有效方式。