离体脱矿年轻恒牙漂白与再矿化治疗的相互影响

Interaction of bleaching and remineralization on the demineralized and extracted young permanent teeth

目的探讨离体脱矿年轻恒牙漂白与再矿化治疗的相互影响。方法选取和制作16个离体的年轻恒牙标本,随机分成A组和B组,各8个标本。两组标本先进行脱矿,B组用美白产品Treswhite进行7次漂白治疗;A组标本浸泡于人唾液中,然后用含氟的Crest牙膏进行再矿化处理。测定并比较四阶段(原始阶段、脱矿后、美白治疗或唾液浸泡后和矿化治疗后)两组牙标本的硬度和颜色数据。结果两组四阶段牙齿硬度组内和组间比较差异均无显著性(﹥0.05)。B组从美白治疗或唾液浸泡后至脱矿后比色值改变最明显,值为6.01±1.94,较A组的3.18±2.44大(﹤0.05)。经再矿化处理后与美白治疗或唾液浸泡后比较,B组值大于A组,但差异无显著性(﹥0.05);经再矿化处理后与脱矿后比较,两组值比较差异无显著性(﹥0.05)。结论漂白治疗对脱矿的离体年轻恒牙的再矿化有促进作用,但其效果不明显;漂白在短期内效果明显,经过长期的再矿化后,牙体色泽的变化会变得不明显,但仍有别于漂白前。

Objective To investigate the interaction of bleaching and remineralization on the demineralized and extracted young permanent teeth. Methods Sixteen enamel specimens prepared from extracted young permanent teeth were measured for Knoop Hardness Number （KHN） with a Leco Microhardness Tester （M-400-H1, St, Joseph, MI）. The color was determined by the Shade Vision （X-Rite, Inc, Grandville, MI）. The specimens were determineralized to achieve the KHN around 170 and they were then randomly assigned to Group A and B （8/group）. Group B received 7 bleaching treatments with treswhite by Opalescence （Ultradent Products, South Jordan, UT） following manufacturer instruction; group A was treated with pooled human saliva. Group B was then treated by a fluoride dentifrice （Crest Regular, Procter and Gamble,Cincinnati, OH）. The KHN and color data （CIELAB） were collected at the baseline （BL）, after-demineralization （AD）, after-bleaching or saliva treatment （AB/S）, and after-remineralization （AR）. The data were analyzed by the One-way ANOVA and Student-newman-Keuls methods. Results There were no significant differences in the KHN values between the two groups at the BL, AL and AB/S. However, after remineratization the KHN increased in both groups. The CIELAB data showed a color change of approximately 8 Delta E after demineralization. After remineralization, the mean KNH value of group A was 200.5KNH,while group B was 220.SKNH, but there was no statistical difference between them（P=0.063）; there was no significant diefference between the AB/S and AR （P=0.207）. The result of AL to AB/S indicated that the color change of group B（AE=6.01） had a significantly higher Delta E than that of group AfAE=3.18）（P=0.007）. Althouhg from AR to AB/S, the color change of group B（AE=4.84） was higer than that of group A（AE=2.38）,there was no significance（P=0.189）. Conclusion Bleaching treatment can facilitate the remineralization of extracted adolescent permanent teeth,but it is not large. Although the remineralization process reduces the effect of bleaching treatment,it is different from before.