Evaluation on the mechanical properties and biocompatibility of the FRP esthetic orthodontic wire for clinical application

本研究的目的是对临床应用的玻璃钢美学矫形丝的力学性能和生物相容性进行评价。研究结果如下：1.玻璃钢丝经水浸后的力学性能。浸水后，滞后环的失活载荷和弹性回复率明显降低。为了防止这种情况，通过R&D方法涂覆Bis-GMA。采用浸渍速度为1 cm/min的研发方法，30天后仍能保持足够的肌肉负荷（D/L 60- 80%）和良好的弹性恢复.为了研制具有生物相容性的CaO-P_2 O_5-SiO_2-Al_2O_3（CPSA）玻璃纤维与PMMA基体复合的FRP丝材，采用光固化聚合法制备了具有足够扭力的矩形木材。以牙科复合树脂为基体的FRP丝的扭转载荷为Ni-Ti丝的1/2。这表明，纤维含量主要贡献弯曲载荷，而使用stigg材料的基体是更有效地改善扭转性能.为了避免结扎线产生的剪切力，对不同曲率半径的改良托槽进行了评价。随着曲率半径的增大，FRP丝的挠度极限和弹性性能的恢复得到改善。结扎弯曲试验表明，该材料具有良好的弹性恢复能力和较高的载荷保持能力.在单接触面和双接触面两种情况下，获得了正畸丝与托槽之间的摩擦特性和摩擦系数。除多晶氧化铝托槽外，FRP丝与托槽的摩擦性能与金属丝相似。

The evaluation on the mechanical properties and biocompatibility of the FRP esthetic orthocontic wire for clinincal appoication is the aim of this research. The results are as follows:1. After the FRP wire have been immersed in mechanical properties through water immersion. The deactivating load and elastic recovery in s hysterisis loop decreased much after water immersion. To prevent this, Bis-GMA was coated by R＆D method. The FRP with this coating by the method of R＆D with dipping speed 1 cm/min., showed sufficient rtention of flesural load (D/L 60-80 %) and good elastic recovery even after 30 days.2. To develop the FRP wires in combination with biocompatible CaO-P_2O_5-SiO_2-Al_2O_3 (CPSA) glass fibers and PMMA matrix by hot drawing method, a photo cure polymerization method was applied to form the rectangular timber with a sufficient torque force. The FRP wire using dental composite resin for matrix showed a torsional load of 1/2 of Ni-Ti wire. This showed that the fiber content mainly contributes to flexural load while the use of stigg materials for the matrix is much more effective for improbing torsional properties.3. To avoid the shear force exerted by ligatures, improved brackets with various radius curvature were evaluated. The limit of deflection of the FRP wire and the recovery of the elastic properties improved with the larger radius curvatures. It was also clarified from ligated bending test that good elastic recovery and high load-retention could be obtained.4. The frictional properties between orthodontic wires and brackets and frictional coefficients were obtained under conditions of single contact plane and double contact planes. The friction properties of FRP wire with brackets were similar to those of metal wires expect for the polycrystalline alumina bracket.