Breier M, Bourauel C, Drescher D
Poliklinik für Kieferorthopädie, Universität zu Köln.
Fortschr Kieferorthop. 1995 May;56(3):165-74. doi: 10.1007/BF02276633.
When applying the angulated face bow, it doesn't seem possible to avoid vertical and transversal forces which occur in addition to the distalization force as moments. By varying the length and angulation of the outer bow, it is possible to influence the force components and the moments in the sagittal plane. In the clinical analysis of the force system it is assumed that the face bow is an ideal rigid system. Only under this presupposition is the assumption valid, that the product of the force and the perpendicular distance to the molar tube is responsible for the size of the moment. Under this assumption, however, all forces and moments created by the deflection of the headgear are not taken into consideration. An experimental analysis of the forces and turning moments which occur indicates that this simplifying geometric point of view does not always correspond to reality. It was evident, e.g., that there is no linear correlation between the force and moment in mesio-distal direction due to the deflection of the outer bow. This effect becomes the more obvious the longer the outer bow of the headgear is.
使用成角面弓时，除了作为力矩的远中移动力之外，似乎无法避免垂直力和横向力的产生。通过改变外弓的长度和角度，可以影响矢状面内的力分量和力矩。在力系统的临床分析中，假设面弓是一个理想的刚性系统。只有在这个前提下，力与到磨牙管的垂直距离的乘积决定力矩大小这一假设才成立。然而，在此假设下，未考虑头帽偏转产生的所有力和力矩。对所产生的力和转动力矩的实验分析表明，这种简化的几何观点并不总是符合实际情况。例如，很明显，由于外弓的偏转，近远中方向的力和力矩之间不存在线性关系。头帽的外弓越长，这种效应就越明显。
