Shields T E, Little R M, Chapko M K
Am J Orthod. 1985 Jan;87(1):27-38. doi: 10.1016/0002-9416(85)90171-x.
Assessment at least 10 years postretention of fifty-four cases previously treated in the permanent-dentition stage with first-premolar extractions, traditional edgewise mechanotherapy, and retention revealed considerable variation among patients. The long-term response to mandibular anterior alignment was unpredictable; no cephalometric parameters, such as maxillary and mandibular incisor proclination, horizontal and vertical growth amounts, mandibular plane angle, etc., were useful in establishing a prognosis. Few associations of value were found between cephalometric parameters and dental-cast measurements, such as overbite, arch length, intercanine width, and overjet. Only a slight tendency was found for incisor inclination to return toward the pretreatment value during the postretention period. It was possible to predict, on the basis of an analysis of pre- and posttreatment cephalometric records, those cases which had greater than 4 mm deepening of overbite postretention as well as those cases which had decreases of 3 mm or more in arch-length postretention. The practical use of these predictions were of limited clinical value, however.
对54例曾在恒牙列期接受第一前磨牙拔除、传统方丝弓矫治及保持治疗的患者进行至少10年的随访评估，结果显示患者之间存在相当大的差异。下颌前牙排齐的长期反应不可预测；没有任何头影测量参数，如上颌和下颌切牙倾斜度、水平和垂直生长量、下颌平面角等，对建立预后有帮助。头影测量参数与牙模型测量值，如覆合、牙弓长度、尖牙间宽度和覆盖之间，几乎没有有价值的关联。仅发现切牙倾斜度在保持期有轻微向治疗前值恢复的趋势。根据治疗前后的头影测量记录分析，可以预测那些保持后覆合加深超过4mm的病例，以及那些保持后牙弓长度减少3mm或更多的病例。然而，这些预测的实际临床价值有限。
