Frictional forces related to self-ligating brackets
Frictional forces related to self-ligating brackets
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DOI：
10.1093/ejo/20.3.283
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发表时间：
1998-06-01
影响因子：
2.6
通讯作者：
Melsen, B
中科院分区：
文献类型：
--
作者：
Pizzoni, L;Ravnholt, G;Melsen, B
正畸牙齿移动可以被视为牙齿在金属丝上滑动，就像珍珠在绳子上滑动一样，力由弹簧或松紧带提供。这种运动意味着钢丝和托槽之间的摩擦，吸收了部分力，并留下不受控制的力作用在牙齿上。摩擦力可能取决于支架结构和线材。因此，在这项研究中，与更传统的配置相反，评估了自锁托槽和β-钛丝的摩擦力。托槽由低摩擦线性滚珠轴承承载，可沿着伸出的弓丝滑动，以最小的（已知的）基本摩擦力，与弓丝平行或成一定角度。两个自锁托槽在其闭合位置使用，无需任何法向力。对四种金属丝进行了摩擦测试：不锈钢和β-钛，具有圆形和矩形横截面。在试验机上以 10 毫米/分钟的速度测量用于克服摩擦和移动支架的力，并减去基本摩擦力。结果表明，圆线的摩擦力低于矩形线，β-钛线的摩擦力明显高于不锈钢线，并且所有支架/线组合的摩擦力随着角度的增加而增加。自锁托槽在所有角度上的摩擦力都明显低于传统托槽，并且通过传统设计的封盖封闭的自锁托槽比通过弹簧封闭的自锁托槽表现出明显更低的摩擦力。托槽设计、钢丝材料和钢丝横截面的选择显着影响连续牙弓系统中作用的力。
Orthodontic tooth movement can be regarded as teeth sliding on a wire like pearls on a string, the force being supplied by springs or elastics. The movement implies friction between wire and bracket, taking up part of the force and leaving an uncontrolled amount to act on the teeth. The friction is likely to depend on bracket construction and wire material. Therefore, in this investigation the friction of self-ligating brackets and beta-titanium wires was evaluated, as opposed to more conventional configurations.Carried by low-friction linear ball bearings, a bracket was made to slide along an out-stretched archwire with minimal (and known) basic friction, either parallel or at an angle to the wire. Two self-ligating brackets were used in their closed position without any normal force. Friction was tested against four wires: stainless steel and beta-titanium, both in round and rectangular cross-sections. The force used to overcome friction and to move the bracket was measured on a testing machine at 10 mm/min, and the basic friction was subtracted.The results show that round wires had a lower friction than rectangular wires, the beta-titanium wires had a markedly higher friction than stainless steel wires, and friction increased with angulation for all bracket/wire combinations. The self-ligating brackets had a markedly lower friction than conventional brackets at all angulations, and self-ligating brackets, closed by the capping of a conventional design, exhibited a significantly lower friction than self-ligating brackets closed by a spring.The selection of bracket design, wire material, and wire cross-section significantly influences the forces acting in a continuous arch system.