Histological changes of periodontal tissue by anti-tumor agents, and study on effective management of dental caries

近年来，在儿童癌症患者中经常观察到抗肿瘤治疗的远期效应。环磷酰胺(CY)是儿童癌症治疗中常用的细胞抑制药物之一。本研究旨在评价环磷酰胺对小鼠牙齿发育的影响。给12日龄ICR小鼠灌胃环磷酰胺(100 mg/kg)。侧位摄软X线片。计算第一磨牙牙根/牙冠长比(R/C)。取第一磨牙制作系列矢状面切片，进行组织形态和免疫组织化学(细胞角蛋白)研究。27d时，实验组的根长约为对照组的60%。实验组的Hertwig‘s上皮根鞘从20d开始消失。我们的结果表明，CY可以诱导和改变HERS的功能缺陷，上皮鞘的破坏抑制了增殖和根的形成。

Recently,late effects of antineoplastic treatment are frequently observed in childhood cancer patients. Cyclophosphamide (CY) is one of the cytostatic drugs commonly used for cancer treatment in children. This study aimed to evaluate the effect of CY on dental development in mice. We treated 12-day-old ICR mice with CY (100 mg/kg, i.p.). Soft X-ray radiographs were obtained in lateral projection. The root / crown length (R/C) ratio of the first molar was calculated. Serial sagittal sections were prepared from the first molars and histomorphological and immunohistochemical (cytokeratin) studies were performed. At 27 days, the root length in the experimental group was approximately 60% of that in the control group. The Hertwig's epithelial root sheath in the experimental group disappeared from 20 days onwards. Our results indicate that CY can induce a defect in and alter the function of HERS and disruption of the epithelial sheath inhibits proliferation and root formation.