乙二胺四乙酸和枸橼酸对细小根管制备的实验研究

Experimental research on preparation of small root canals with EDTA and cirtric acid

目的研究乙二胺四乙酸（ＥＤＴＡ）和枸橼酸对细小根管的作用，为临床应用提供实验依据。方法甲乙两组分别对１４个离体牙细小根管用１７％ＥＤＴＡ和５０％枸橼酸处理３天。结果用１７％ＥＤＴＡ溶液经过３天处理的１４个细小根管全部有效，总有效率１００％，且扩大深入达４ｍｍ以上的有１１个根管，有９个根管达到工作长度。用５０％枸橼酸溶液经过３天处理的１４个细小根管中有效１１个，无效３个，总有效率７８．５７％，有８个根管扩大深入达４ｍｍ以上，并达到工作长度。甲乙两组的扩大深入程度，经统计学处理有显著性差异（Ｐ＜０．０１）。

Objective To study the effects of EDTA and citric acid on small root canals so as to provide experimental basis for clinical applications.Methods 17% EDTA and 50% citric acid are applied to Group A and Group B respectively for three days, each group having 14 extracted teeth with small root canals. The data obtained during the three days' experiment are analyzed with statistic method. Results The 14 small root canals applied with 17% EDTA solution for three days are all effective, the overall effectiveness rate being 100% and 11 small root canals show an expansion level of 4mm or over , 9 of which reach the length required for treatment, 11 out of the 14 small root canals applied with 50% citric acid solution for three days are effective (three are not effective), the overall effectiveness rate being 78.57%. 8 small root canals show an expansion level of over 4 mm and all of them reach the length required for treatment. Based upon statistic treatment, the expansion level of small root canals of both Group A and Group B has an obvious difference ( P <0.01) after the application. Conclusion EDTA should be the recommended medicine for chemical preparation of small root canals.