Effect of brushing and beverages on surface roughness of ceramic brackets

Abstract Introduction When introduced into the oral environment, the ceramic brackets may undergo change their structure caused by the process of chemical and mechanical degradation of the material. Objective This study evaluated the surface roughness of ceramic brackets and whether it is altered by toothbrushing process and diet solutions. Material and method Seven ceramic brackets of four commercial brands were tested: two monocrystalline and two polycrystalline. The brackets were immersed in solutions of coffee, red wine, Coke, black tea and artificial saliva for 21 days. Another group of brackets of each brand were also immersed in the same solutions and for an equal time, but with daily brushing performed by a toothbrushing machine. The surface roughness (Ra) was analyzed by a Roughness Tester (Surftest SJ–400,Mitutoyo®) before and after 24 hours, 7, 14 and 21 days. The data were evaluated by the Analysis of Multivariate Profiles, Analysis of Variance (ANOVA), multiple comparison test of means. Result The results of Ra and its change after 21 days were: Ra mean of Allure = 0.277μm (change = 0.002μm), Inspire Ice = 0.262μm (change = 0.013μm), Radiance = 0.177μm change = 0.009μm), Transcend = 0.367μm (change = 0.019μm). Conclusion the surface roughness of the ceramic brackets increased after 21 days of immersion in the solutions, and the immersion time was a significant factor. However, this change in the surface roughness was similar for the monocrystalline and polycrystalline brackets, as well as for the different solutions. Brushing did not change the surface roughness of ceramic brackets.

摘要 当陶瓷托槽被植入口腔环境后，可能会因材料发生化学与机械降解过程而出现结构变化。
研究目的 本研究旨在评估陶瓷托槽的表面粗糙度，以及刷牙过程与饮食溶液是否会对其产生改变。
材料与方法 本研究测试了4个商业品牌的7款陶瓷托槽：其中2款为单晶陶瓷托槽，2款为多晶陶瓷托槽。将托槽分别浸泡于咖啡、红酒、可乐、红茶及人工唾液溶液中，持续21天。另取同品牌的托槽组，同样浸泡于上述溶液且时长一致，但每日通过牙刷试验机进行刷牙操作。分别在实验初始、24小时后、第7、14及21天，采用表面粗糙度测试仪（Surftest SJ–400，三丰®（Mitutoyo®））对表面粗糙度（Ra）进行检测。实验数据通过多变量轮廓分析、方差分析（ANOVA）及均值多重比较检验进行统计学评估。
研究结果 21天后的表面粗糙度（Ra）及其变化量如下：Allure品牌均值为0.277μm（变化量0.002μm），Inspire Ice品牌为0.262μm（变化量0.013μm），Radiance品牌为0.177μm（变化量0.009μm），Transcend品牌为0.367μm（变化量0.019μm）。
研究结论 经21天溶液浸泡后，陶瓷托槽的表面粗糙度有所升高，且浸泡时长为影响该指标的显著因素。不过，单晶与多晶陶瓷托槽之间以及不同饮食溶液之间的表面粗糙度变化幅度并无显著差异。刷牙操作并未对陶瓷托槽的表面粗糙度产生明显改变。