Postgraduate Program in Dentistry, School of Dentistry, University of Taubaté, Taubaté, Brazil.
Braz Dent J. 2021 Jan-Feb;32(1):53-58. doi: 10.1590/0103-6440202103700.
The endodontic revascularization may be an alternative treatment for necrotic immature teeth, however, several treatment steps may cause tooth discoloration. This study evaluated the use of three calcium silicate-based cements with different radiopacifying agents on the color alteration (∆E) of extracted premolars after simulation of revascularization. Forty single rooted extracted premolars were shaped with #1-6 gates Glidden drills, rinsed with sodium hypochlorite, and filled with fresh human blood. Three calcium silicate-based cements with different radiopacifying agents (bismuth oxide - CSBi, calcium tungstate - CSW, and zirconium oxide - CSZr) were applied over the blood clot (n=10). The control group received the application of a temporary zinc oxide-based cement (TFZn) (n=10). ∆E was measured with a spectrophotometer, using the Lab* color system of the International Commission on Illumination (CIELab), in different times: prior to the preparation of the access cavity (t0); right after treatment (t1); and after one (t2), two (t3), three (t4) and four (t5) months. The tooth site for color evaluation was standardized by silicon matrix, the color reading was performed 3 times per tooth, and the teeth were stored in 37º water between evaluations. ∆E, whiteness (WID index) and yellowness (b*) were evaluated. Data were subjected to one-way ANOVA and repeated measures ANOVA, followed by Tukey's post hoc test (α=0.05). All groups were similar in ∆E1 (t0-t1). The ∆E was the lowest and constant in the control group. In all evaluation times, CSBi presented the highest ∆E (p<0.01). CSW and CSZr were similar in all evaluated times and presented intermediate ∆E values. WID index from CSBi and CSW presented more distancing from 'white' reference. CSBi presented the greatest decrease in yellowness (b* value). The cement containing bismuth oxide presented the highest color alteration values. All tested calcium silicate-based cements presented clinically perceptible discoloration. Calcium tungstate and zirconium oxide may be used as alternative radiopacifiers to decrease tooth discoloration after endodontic tooth revascularization.
牙髓血运重建术可能是治疗未成熟坏死恒牙的一种替代方法，但多个治疗步骤可能会导致牙齿变色。本研究模拟血运重建术后，评估了三种不同的含放射阻射剂的硅酸钙基水泥对离体前磨牙颜色改变（∆E）的影响。40 颗单根前磨牙使用#1-6 号 Gates Glidden 扩孔钻制备根管，用次氯酸钠冲洗，并用新鲜人血填充。将三种不同放射阻射剂的硅酸钙基水泥（氧化铋-CSBi、钨酸钙-CSW 和氧化锆-CSZr）分别涂覆于血凝块上（n=10）。对照组则使用临时氧化锌基水泥（TFZn）（n=10）。采用国际照明委员会（CIELab）的 Lab颜色系统，使用分光光度计，在不同时间点（制备开髓口前（t0）；治疗后即刻（t1）；以及 1 个月（t2）、2 个月（t3）、3 个月（t4）和 4 个月（t5））测量 ∆E。使用硅基质对牙齿的颜色评估部位进行标准化，每颗牙进行 3 次颜色读数，评估之间将牙齿储存在 37°C 水中。评估 ∆E、白度（WID 指数）和黄度（b值）。数据采用单因素方差分析和重复测量方差分析，然后采用 Tukey 事后检验（α=0.05）。所有组在 ∆E1（t0-t1）时均相似。对照组的 ∆E 最低且保持不变。在所有评估时间内，CSBi 的 ∆E 最高（p<0.01）。CSW 和 CSZr 在所有评估时间内相似，呈现出中等的 ∆E 值。CSBi 和 CSW 的 WID 指数与“白”参考值的差距更大。CSBi 呈现出最大的黄度降低（b*值）。含氧化铋的水泥呈现出最高的颜色改变值。所有测试的硅酸钙基水泥均表现出临床可察觉的变色。钨酸钙和氧化锆可用作牙髓血运重建术后减少牙齿变色的替代放射阻射剂。
