课题背景：传统酸蚀剂对牙本质、牙髓组织具有明显刺激作用。含羧酸或聚羧酸的自蚀黏接系统中的羧酸刺激性较小，并能与羟基磷灰石反应生成羧酸钙盐，通过形成的离子键，化学吸附于牙体硬组织表面。由于羧酸酸性较弱，如何评价其在牙本质黏接过程中酸蚀脱矿作用尚不明确。

应用要点：①通过扫描电镜对牙本质小管管径测量分析，分析不同酸蚀处理方法对牙本质脱矿的影响。②多元羧酸对于牙本质的脱矿效果与其种类和处理时间有关，延长酒石酸、柠檬酸的处理时间至 60 s可获得与传统酸蚀剂磷酸相当的脱矿效果，苹果酸脱矿效果较酒石酸、柠檬酸弱。

同行评价：实验针对采用磷酸溶液牙本质进行酸蚀处理的方法中，有可能导致牙本质中胶原蛋白的变性，不利于黏接剂的润湿和渗透，并且可能对牙髓有刺激作用的问题，采用有机多元羧酸对牙本质表面进行酸蚀，通过扫描电镜对处理后的表面进行观察。此课题提出的问题具有针对性，对于新的酸蚀剂研究可提供实验依据。

摘要
目的: 酸性较弱的多元羧酸对牙体硬组织具有化学吸附作用，故部分牙体黏接材料采用多元羧酸及其衍生物作为预处理剂。比较苹果酸、酒石酸、柠檬酸和传统酸蚀剂磷酸对牙本质的脱钙作用，分析多元羧酸的酸蚀能力。
方法：实验于2006-10/2007-04在上海交通大学医学院附属第九人民医院和浙江大学医学院附属第一医院口腔科完成。采用150 g/L苹果酸、150 g/L酒石酸、150 g/L柠檬酸溶液分别酸蚀牙本质60 s，360 g/L磷酸酸蚀牙本质15 s，扫描电镜下观察牙本质处理前后表面形貌及牙本质小管直径，方差分析比较不同酸处理对牙本质小管直径大小的影响差异。
结果：①扫描电镜下见未酸蚀样本的牙本质小管开口狭小。酸蚀处理后牙本质表面平坦、清晰，覆盖的玷污层基本去除，管周牙本质脱矿明显，牙质小管开口扩大、敞开。②不同种类酸溶液处理后牙本质脱矿，牙本质小管直径明显增大（P < 0.01）。磷酸酸蚀15 s、柠檬酸、酒石酸酸蚀60 s的牙本质小管直径大小无差异（P > 0.05），明显大于苹果酸酸蚀60 s的小管直径（P < 0.01）。
结论：苹果酸的脱矿作用较弱，适当延长酒石酸、柠檬酸的处理时间可获得与磷酸酸蚀相当的牙本质脱矿效果。
关键词：羧酸；磷酸；牙本质小管；脱钙；生物材料 ；磷酸；牙本质小管；脱钙；生物材料

沈晴昳，傅柏平，孙皎.多元羧酸和磷酸对牙本质脱钙作用的比较[J].中国组织工程研究与临床康复，2008，12(6):1055-1058
[www.zglckf.com/zglckf/ejournal/upfiles/08-6/6k-1055(ps).pdf]

Comparison of dentin decalcification between polycarboxylic acids and phosphoric acid

Abstract

AIM：Polycarboxylic acids with poor acidity are chemical adhesive to the dental hard tissues, thus polycarboxylic acids and their derivates can be used as pretreating agents for dental adhesive materials. This study was designed to compare the dentin decalcification of three carboxylic acids (malic, tartaric and citric) with phosphoric acid.
METHODS: The experiment was carried out in the Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University and the Department of Stomatology in the First Affiliated Hospital of Medical College, Zhejiang University from October 2006 to April 2007. Dentin was etched with 150 g/L malic acid, 150 g/L tartaric acid or 150 g/L citric acid solutions for 60 seconds, respectively, as well as 360 g/L phosphoric acid for 15 seconds. The surface morphology of dentin was observed with scanning electron microscopy (SEM) and the diameter of dentinal tubules was measured. The influences of different acids on the diameter of dentinal tubules were determined by using analysis of variance.
RESULTS: ①SEM results displayed that, the gap of dentinal tubules was narrow in the untreated dentins. After acid etching, the dentins were flat, distinct and clean, with the absence of stains and the presence of peritubular dentin decalcification. The gap of dentinal tubules was enlarged.②Tubular diameters were significantly increased after acid etching (P < 0.01). There were no significant differences in the tubular diameter among phosphoric acid treatment for 15 seconds, citric acid for 60 seconds and tartaric acid for 60 seconds (P > 0.05). And the tubule diameter of dentin treated by phosphate, citric or tartaric acids was significantly broader than that treated by malic acid (P < 0.01).
CONCLUSION: The demineralization capabilities of citric acid and tartaric acid to dentin are as powerful as phosphoric acid by increasing the application time, while the demineralization power of malic acid is much weaker.

Shen QY, Fu BP, Sun J.Comparison of dentin decalcification between polycarboxylic acids and phosphoric acid.Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu 2008;12(6):1055-1058(China)
[www.zglckf.com/zglckf/ejournal/upfiles/08-6/6k-1055(ps).pdf]