Stamm T, Vehring A, Ehmer U, Bollmann F
Department of Orthodontics, University of Münster, Germany.
J Orofac Orthop. 1998;59(4):237-45. doi: 10.1007/BF01579168.
The condylar axiographic tracings of 23 asymptomatic adult volunteers (Helkimo-index DiO) with Class II/2 axiography relationships were compared to tracings of an analogous group (DiO; n = 30) with normal occlusion. The obtained measurements were evaluated statistically and discussed with respect to possible recording errors.
The open-close movement proceeded uncharacteristically, differences existed only in protrusion, mediotrusion and their combined rotation component. In Class II/2 cases an approximately 7 degrees higher angle of the condylar path inclination (CPI) was measured. The Class II/2 group rotated to a significantly higher angle in protrusive and mediotrusive movements and showed longer condylar path lengths than the control group. Another significant difference was found in the location of maximum CPI values and maximum rotation angles within the condylar path, because in no case was isolated rotation or translation of the hinge axis observed.
The temporomandibular joint of Class II/2 individuals shows a wider range of motion than joints of subjects with normal occlusion. The reduced capacity of motion which was assumed to exist in a so-called hack-bite could not be backed up for Class II/2 deep bite cases. The investigated differences cannot be seen as pathomechanisms, because all participants were clinically free of dysfunction. The neuromuscular engram to overcome the overbite controls a complex spatial motion pattern which cannot be described by a simplified mechanical abstraction of motion in the sagittal plane. The temporomandibular joint with its complex pattern of movement is able to create physiological mechanisms of compensation to react to different dental and skeletal features.
将23名具有安氏II类2分类错牙合关系的无症状成年志愿者（赫尔基莫指数DiO）的髁突轴描记图与30名具有正常牙合关系的类似组（DiO）的描记图进行比较。对获得的测量结果进行统计学评估，并就可能的记录误差进行讨论。
开闭运动异常进行，仅在前伸、侧方运动及其组合旋转分量上存在差异。在安氏II类2分类病例中，髁突路径倾斜角（CPI）测量值约高7度。安氏II类2分类组在前伸和侧方运动中旋转角度明显更高，且髁突路径长度比对照组更长。在髁突路径内最大CPI值和最大旋转角度的位置也发现了另一个显著差异，因为在任何情况下都未观察到铰链轴的孤立旋转或平移。
安氏II类2分类个体的颞下颌关节比正常牙合个体的关节运动范围更广。所谓“切牙合”中假定存在的运动能力降低在安氏II类2分类深覆牙合病例中无法得到证实。所研究的差异不能被视为病理机制，因为所有参与者在临床上均无功能障碍。克服深覆牙合的神经肌肉记忆控制着一种复杂的空间运动模式，这种模式无法通过矢状面运动的简化机械抽象来描述。具有复杂运动模式的颞下颌关节能够产生生理补偿机制以应对不同的牙齿和骨骼特征。
