变色牙与Vitapan Classical比色板色标的色差分析

目的 研究Vitapan Classical比色板是否能够有效地评价牙齿漂白的疗效。方法 收集2009年2月-2014年7月接受Beyond冷光美白病例67例，用Vitapan Classical比色板评价疗效，计算不能在该比色板中找到对应色标的病例比例及能找到对应色标的变色牙与对应色标间的色差值。结果 64%（16/25）的四环素牙和28%（17/61）的氟斑牙不能找到对应色标，而全部黄牙均有对应色标，3组间差异均有统计学意义（P=0.000）。有色标对应的四环素牙与氟斑牙、四环素牙与黄牙间ΔL*、Δb*及ΔE的差异有统计学意义，氟斑牙与黄牙间这3项色度值的差异无统计学意义，3类变色牙间Δa*的差异无统计学意义。结论 Vitapan Classical比色板不能够有效地评价牙齿漂白的疗效，尤其不适用于四环素牙及氟斑牙，应对该评价方法加以改进。

Analysis of the color difference between discolored teeth and corresponding shade tabs in Vitapan Classical shade ;guide

Objective To analyze whether Vitapan Classical shade guide could be used to evaluate effectively the effect of tooth whitening. Methods A total of 67 patients underwent Beyond cold light tooth whitening between February 2009 and July 2014. The effect of treatment was evaluated by Vitapan Classical shade guide. The percentage of discolored teeth that could not be matched by the aforementioned shade guide was calculated. By contrast, the color difference between discolored teeth and corresponding shade tabs was calculated for discolored teeth that could be matched by the shade guide. Results Approximately 64% (16/25) of tetracycline teeth and 28% (17/61) of mottled-enamel teeth could not be matched using the Vitapan Classical shade guide, but yellow teeth were all matched, and the difference between any pair of teeth was statistically significant (P=0.000). For discolored teeth that could be matched, statistically significant difference was found in the ΔL*,Δb*, and ΔE between tetracycline and yellow teeth, as well as between tetracycline and mottled-enamel teeth. However, no statistically significant difference was found between mottled-enamel and yellow teeth. Moreover, no statistically significant difference was found in the Δa* among the three groups. Conclusion Vitapan Classical shade guide could not be used to evaluate effectively the effect of tooth whitening, especially for tetracycline and mottled-enamel teeth. The evaluating method should be improved.