Taqa Amer A, Al-Hafidh Nada Nashee, Al-Abbood Mohammed T Sulaiman
Department of Dental Basic Science, College of Dentistry, University of Mosul, Mosul, Iraq.
Department of Pedodontics, Orthodontics and Preventive Dentistry, College of Dentistry, University of Mosul, Mosul, Iraq.
J Orthod Sci. 2021 Aug 4;10:14. doi: 10.4103/jos.JOS_55_20. eCollection 2021.
Stainless steel and nickel-titanium wires are commonly used in fixed orthodontic appliances. Orthodontists often prescribe fluoride gel to avoid demineralization of teeth. This study investigated the effect of acidulated phosphate fluoride gel on the tensile properties, surface morphology and surface chemical composition of stainless steel and nickel-titanium wires.
Forty samples of stainless steel and nickel-titanium wires were examined, twenty for each type. Each wire type was divided into four subgroups. The first subgroup was not immersed in fluoride gel and considered as control, while the other three subgroups were immersed in 10 mL of fluoride gel for different periods of time. Then, the wires were removed from the gel, rinsed in a distilled water and left to dry. The ultimate tensile force of each wire was measured using a tensile testing machine. Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to examine the control and 24 h immersed subgroups.
One-way analysis of variance ANOVA showed that there were no significant differences in the ultimate tensile forces between control and fluoride-treated subgroups ( = 0.172 for SS wires and = 0.672 for NiTi wires). However, changes in the surface morphology and elemental composition of wires were shown by the SEM and EDX.
Although immersion of stainless steel and nickel-titanium wires in the fluoride gel did not affect their tensile properties, however, surface deterioration was evident. So, further investigations are recommended to study the effect of these changes on the oral health of patients.
不锈钢丝和镍钛丝常用于固定正畸矫治器。正畸医生经常开氟化物凝胶来避免牙齿脱矿。本研究调查了酸性磷酸氟凝胶对不锈钢丝和镍钛丝拉伸性能、表面形态和表面化学成分的影响。
检查了40根不锈钢丝和镍钛丝样本，每种类型各20根。每种丝材类型分为四个亚组。第一亚组不浸入氟化物凝胶，作为对照组，而其他三个亚组分别浸入10 mL氟化物凝胶不同时间。然后，将丝材从凝胶中取出，用蒸馏水冲洗并晾干。使用拉伸试验机测量每根丝材的极限拉伸力。用扫描电子显微镜（SEM）和能量色散X射线光谱仪（EDX）检查对照组和浸泡24小时的亚组。
单因素方差分析表明，对照组和氟化物处理亚组之间的极限拉伸力没有显著差异（不锈钢丝 = 0.172，镍钛丝 = 0.672）。然而，SEM和EDX显示了丝材表面形态和元素组成的变化。
虽然将不锈钢丝和镍钛丝浸入氟化物凝胶中不会影响其拉伸性能，但是表面劣化明显。因此，建议进一步研究这些变化对患者口腔健康的影响。
