• 论著（临床研究） •

### 17%EDTA不同处理时间对根面超微结构的影响

1. 上海交通大学 医学院附属第九人民医院牙周病科, 上海市口腔医学重点实验室， 上海 200011
• 出版日期:2016-07-28 发布日期:2016-08-31
• 通讯作者: 束蓉, 电子信箱: shurong123@hotmail.com。
• 作者简介:张丰婧（1992—）， 女， 硕士生; 电子信箱: periozhang@163.com。

### Effect of treatment with 17% EDTA for different periods of time on the microstructure of root surfaces

ZHANG Feng-jing, SHU Rong

1. Shanghai Key Laboratory of Stomatology, Department of Periodontology, Shanghai Ninth Peoples Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
• Online:2016-07-28 Published:2016-08-31

Abstract:

Objective To explore the effect of treatment with 17% EDTA gel and solution for different periods of time on the microstructure of root surfaces and compare the effect between 17% EDTA gel and solution and 24% EDTA solution. Methods Thirty freshly extracted teeth from patients with periodontitis were treated with scaling and root planing (SRP), and dentin fragments and cementum fragments were prepared. These fragments were randomly assigned to the A group treated with saline solution for 3 min, the B group treated with 24% EDTA solution for 3 min, the C group treated with 17% EDTA gel for 3 min, the D group treated with 17% EDTA gel for 5 min, the E group treated with 17% EDTA solution for 3 min, and the F group treated with 17% EDTA solution for 5 min. Scanning electron microscopy was used to observe the microstructure of root surfaces. Results ①The dentin on root surfaces: There were no exposed dentin tubules on the surface of dentin in the A group. The number of open dentin tubules in the B group was the largest and the exposure was the clearest, followed by the D group and F group. The C group and E group had the fewest open dentin tubules, where many blocked tubules existed. ②The cementum on root surfaces: Root surfaces in all groups were clean and the smear layer was removed except the A group. The cementum demineralization in group B was presented significantly and collagen fibers were exposed clearly. The D and F groups showed partial cementum demineralization and collagen fibers on the surface of cementum were lumpish with no significant spatial conformation. The cementum demineralization in the C and E groups was not significant with no exposure of collagen fibers. Conclusion There is no significant difference in the treatment of root surfaces with 17% EDTA gel and solution. When extending the treatment time from 3 min to 5 min, the effect of 17% EDTA becomes better, but is still inferior to 24% EDTA solution.