Frye Linda, Diedrich Peter R, Kinzinger Gero S M
Department of Orthodontics, RWTH University, Aachen, Germany.
J Orofac Orthop. 2009 Nov;70(6):511-27. doi: 10.1007/s00056-009-9938-6. Epub 2009 Dec 4.
The aim of this clinical trial was to investigate and compare outcomes after treating a skeletal Class II malocclusion with two fixed functional orthodontic appliances, the Herbst appliance and the Functional Mandibular Advancer, by evaluating their skeletal and dentoalveolar effects and the repercussion on the profile in relation to patient age.
The sample population comprised 42 subjects with skeletal Class II malocclusion. They were divided into two groups depending on age. Group A (n = 21) included nine female subjects aged up to 12 years and twelve male subjects aged up to 14 years. Group B (n = 21) comprised twelve females older than 12 years and nine males older than 14 years. Treatment course was documented cephalometricly. The net therapeutic effects were calculated with reference to the control group.
A significant reduction of the overjet was achieved in both treatment groups. Within the two groups there were no significant sagittal effects in terms of mandibular advancement. However, there was an inhibiting effect on the maxilla, which counteracted the natural growth process. Significant changes in vertical direction were detected mainly in the younger patients in the sense of lengthening of the lower face. Significant dental changes were predominantly found in the group of older patients. For instance, treatment with fixed functional orthodontic appliances led to retrusion of the upper incisors by a mean of 2.21 mm +/- 2.66 mm (p = 0.0015), protrusion of the lower incisors by a mean of 2.28 mm +/- 2.39 mm (p = <or= 0.0001) and distalization of the six-year molars by a mean of 1.12 mm +/- 2.15 mm (p = 0.0315). The skeletal and dental effects achieved by treatment did not correlate directly with the soft tissue adaptations. Generally speaking, far more significant effects on the soft tissue profile were identified in the younger patients. Significant reduction in convexity of the bony profile was similarly more pronounced than in the older age group (N-A-Pog: group A: -4.46 +/- 3.00 (p <or= 0.0001), group B: 3.93 +/- 3.25 (p <or= 0.0001).
Only slight skeletal sagittal effects, which were independent of age, were observed as a result of treatment with fixed functional orthodontic appliances. The younger the patients, the greater any growth-inhibiting effect on the maxilla will be. There is a greater increase in facial height during treatment than would have been expected from growth without any such influence. The compensatory dental effects increase with patient age.
本临床试验旨在通过评估两种固定功能矫治器（Herbst矫治器和功能性下颌前导矫治器）对骨骼和牙牙槽的影响以及对不同年龄患者侧貌的影响，来研究和比较治疗骨性II类错牙合畸形后的效果。
样本包括42例骨性II类错牙合畸形患者。根据年龄将他们分为两组。A组（n = 21）包括9名12岁及以下的女性患者和12名14岁及以下的男性患者。B组（n = 21）包括12名12岁以上的女性患者和9名14岁以上的男性患者。采用头影测量法记录治疗过程。参照对照组计算净治疗效果。
两个治疗组的覆盖均显著减小。两组在下颌前伸方面均未观察到显著的矢状向效果。然而，对上颌有抑制作用，抵消了自然生长过程。主要在年轻患者中检测到垂直方向的显著变化，表现为下面高延长。显著的牙齿变化主要出现在年龄较大的患者组。例如，使用固定功能矫治器治疗导致上颌切牙平均后缩2.21 mm±2.66 mm（p = 0.0015），下颌切牙平均前突2.28 mm±2.39 mm（p =≤0.0001），第一恒磨牙平均远中移动1.12 mm±2.15 mm（p = 0.0315）。治疗所获得的骨骼和牙齿效果与软组织适应性没有直接关联。一般来说，年轻患者对软组织侧貌的影响更为显著。骨性侧貌凸度的显著减小在年轻患者组中同样比老年组更为明显（鼻根点-鼻下点-颏前点：A组：-4.46±3.00（p≤0.0001），B组：3.93±3.25（p≤0.0001））。
使用固定功能矫治器治疗后仅观察到轻微的、与年龄无关的骨骼矢状向效果。患者年龄越小，对上颌的生长抑制作用越大。治疗期间面部高度的增加比无此影响时的生长预期更大。代偿性牙齿效果随患者年龄增加。
