酸蚀液加氟对托槽抗剪切力和釉质表面氟化物沉积的影响

Effect of fluorided etching fluid on the shear bond strength and the deposition on the surface of enamel

目的:寻找在酸蚀液中加氟的最佳浓度,在保证托槽最大抗剪切强度的条件下达到最大的防龋效果。方法:应用含不同氟浓度的酸蚀液酸蚀牙釉质后,在酸蚀粘结后的不同时期,检测托槽的抗剪切强度,并用扫描电镜观察釉质表面形态。采用SPSS10.0统计软件包对抗剪切强度结果进行统计学分析。结果:含3%氟化钠组的抗剪切强度显著低于其余各组(P<0.05),而其余各组之间无显著性差异(P>0.05)。酸蚀液处理后的牙釉质表面沉积物的数量与酸蚀后的时间和含氟化钠的浓度增加而增加,含3%氟化钠的酸蚀液组沉积物数量最多。结论:在35%磷酸液中加入2%的氟化钠既能有效防龋,又不影响托槽的粘结力。

PURPOSE: The aim of this study was to find the best concentration of fluorided etching acid in the dental clinic which had both the best shear bond strength and the maximal anti-caries effect. METHODS: 84 extracted human premolars were divided into four groups of 21 teeth each. The enamel of each group was conditioned with 35% phosphoric acid containing 0%, 1.23%, 2%, 3% NaF. The shear bond strength was tested by bond strength machine and the enamel morphology was observed by scanning electron microscopy at once, 1 week, 4 weeks, 12 weeks, 24 weeks after etching. The shear bond strength was statistically analyzed by SPSS10.0 software. RESTULS: The shear bond strength of the group whose acid containing 3%NaF was less than the others significantly(P<0.05); and there was no significant difference among the other groups(P>0.05). The amount of the deposition on the surface of enamel after etching was increased with the time after etching and the concentration of NaF increasing. CONCLUSIONS: 2% NaF added to 35% phosphoric acid has both the best bond strength and the best effect of preventing enamel from caries.