Establishment of a design model of magnetic attachment with new magnetic material

doi:10.3969/j.issn.2095-4344.2015.03.024

Abstract

Abstract:

BACKGROUND: Studies have demonstrated that neodymium iron boron (NdFeB) is a new kind of permanent magnet material with size reduction, light quality and high performance. The magnetic energy product of NdFeB N52 newly developed is 53MGOe, and the N52 is not used in dental field.
OBJECTIVE: To establish and evaluate the model of NdFeB magnetic attachment.
METHODS: The NdFeB magnetic material, Fe-Ni soft magnetic alloy and HPM75 stainless steel were bought and cut by the size of model structure with the “cup” type of closed magnetic field, to prepare the permanent magnet, keeper, yoke, shield disk and ring. All the parts were assembled, welded, chromed and magnetized. The magnetic force and magnetic induction intensity of 10 specimens were tested and recorded.
RESULTS AND CONCLUSION: Ten models of magnetic attachment with closed magnetic field were established. The simulated magnetic force and actual magnetic force were 87.6 mT and (48.930±2.827) mT. The simulated magnetic induction intensity and actual magnetic induction intensity were 0.331 mT and 2.7 mT in the side, 6.52 mT and 18.7 mT in the top. The geometric diagram between the magnetic force and distance was simulated by the 3D simulation software. The results showed the magnetic force decreased rapidly with the distance increase between the magnet and keeper when the distance became from close contact to a gap of 0.1 mm. The magnetic force with a gap of 0.1 mm between the magnet and the keeper was decreased to about 24% of the magnetic force at zero gap. The magnetic force decreased slowly with the distance increase from 0.1 mm gap, and then the magnetic force was almost zero with the 0.5 mm gap. The clinical demand and the safety standard of magnetic leakage can be meted with the model of magnetic attachment by using the new magnetic material.

中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程

全文链接：

Key words: Denture Precision Attachment, Models, Structural, Dentures

CLC Number:

R318

Jiang Rui, Nie Er-min, Zhang Chun-yuan, Zeng Jin-di, Tan Ji-zhou. Establishment of a design model of magnetic attachment with new magnetic material[J]. Chinese Journal of Tissue Engineering Research, 2015, 19(3): 460-464.

Figures/Tables 2

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