Pinto Shelon Cristina S, Pochapski Márcia T, Wambier Denise S, Pilatti Gibson L, Santos Fábio A
Department of Dentistry, Ponta Grossa State University, Paraná, Brazil.
J Oral Sci. 2010 Mar;52(1):23-32. doi: 10.2334/josnusd.52.23.
This study was done to assess the influence of the topical application of two different desensitizing agents on dentin permeability and dentinal tubule occlusion. Twenty-one rats provided 84 teeth: 36 for the in vitro and 48 for the in vivo investigation. The following agents were tested: Group 1, 2% potassium nitrate plus 2% sodium fluoride gel; Group 2, 5% sodium fluoride varnish; Group 3, 3% hydroxyethylcellulose gel (control). Cervical cavities were prepared and EDTA was applied to expose the dentinal tubules. After each treatment, Evans blue dye was applied to the teeth. Dentin permeability, scanning electron microscope (SEM) sections, and energy dispersive X-ray (EDX) were analyzed. One-way ANOVA was used to compare the data. There were significant differences (P < 0.05) among groups for dentin permeability, number of tubules/mm(2), tubule area and tubular diameter. Groups 1 and 2 (both in vitro and in vivo) showed open and partially occluded tubules. Group 3 had the most open tubules. EDX revealed similar composition for both experimental conditions. Within the limits of the study, 2% nitrate potassium plus 2% sodium fluoride gel and 5% fluoride varnish decreased the dentin permeability, resulting in partial tubular occlusion.
本研究旨在评估两种不同脱敏剂局部应用对牙本质通透性和牙本质小管封闭的影响。21只大鼠提供了84颗牙齿：36颗用于体外研究，48颗用于体内研究。测试了以下制剂：第1组，2%硝酸钾加2%氟化钠凝胶；第2组，5%氟化钠清漆；第3组，3%羟乙基纤维素凝胶（对照）。制备颈部洞型并应用乙二胺四乙酸以暴露牙本质小管。每次处理后，将伊文思蓝染料应用于牙齿。分析牙本质通透性、扫描电子显微镜（SEM）切片和能量色散X射线（EDX）。采用单因素方差分析比较数据。各组之间在牙本质通透性、每平方毫米小管数量、小管面积和小管直径方面存在显著差异（P < 0.05）。第1组和第2组（体外和体内）均显示小管开放和部分封闭。第3组的小管开放程度最高。EDX显示两种实验条件下的成分相似。在本研究范围内，2%硝酸钾加2%氟化钠凝胶和5%氟化钠清漆降低了牙本质通透性，导致小管部分封闭。
