Departament of Orthodontics, University of Barcelona, Orthodontic Department, Feixa Llarga St., Hospitalet del Llobregat, 08907 Barcelona, Spain.
Med Oral Patol Oral Cir Bucal. 2010 Nov 1;15(6):e930-5.
The overeruption of upper molars due to the premature loss of antagonist teeth can be treated with the help of miniscrews. The aim of this study was to evaluate the movement of a typodont molar according to the biomechanical approach used with miniscrews.
The study was conducted with four plaster models filled with typodont wax. In each model we used one absolute anchorage on the palatal side and another on the buccal side in different positions, thus generating four different biomechanical systems. A force of 150 g was applied to each side of the resin tooth. Periapical radiographs were taken preintrusion and immediately after completion of the intrusion. Photographs were taken in both the sagittal and occlusal planes every 3 min. The radiographic films and photographs were measured and compared.
A vertical movement of the molar was observed in all the models, with system 4 showing the greatest movement. Rotation in the occlusal plane only occurred in system 2, while in system 1 there was a change in the axial axis of 37 degrees.
The anchorage site and the combination of forces applied may determine the resulting tooth movement.
由于对颌牙过早缺失导致上颌磨牙过度萌出，可以通过微型种植体来进行治疗。本研究旨在评估使用微型种植体的生物力学方法对典型磨牙的移动。
本研究共使用了四个充满典型牙蜡的石膏模型。在每个模型中，我们在腭侧和颊侧使用了一个绝对支抗，从而产生了四个不同的生物力学系统。在树脂牙的每一侧施加 150 克的力。在推磨牙入之前和推磨牙入完成后立即拍摄根尖片。每隔 3 分钟在矢状面和咬合面拍摄照片。对 X 光片和照片进行测量和比较。
所有模型均观察到磨牙的垂直移动，其中系统 4 显示的移动最大。在咬合面仅观察到系统 2 发生旋转，而在系统 1 中，轴向轴发生了 37 度的变化。
锚固部位和应用力的组合可能决定最终的牙齿移动。
