Early extraction of first permanent molars (FPMs) is generally considered successful when the second permanent molar and premolar come into contact, regardless of whether the patient has a healthy occlusion. In this study, we aimed to investigate cases in which early extraction had a successful prognosis.

中文翻译：

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第一恒磨牙的早期拔除：一项为期五年的随访研究。

当第二恒磨牙和前磨牙接触时，无论患者是否有健康的咬合，早期拔除第一恒磨牙 (FPM) 通常被认为是成功的。在这项研究中，我们旨在调查早期拔牙具有成功预后的病例。