Abstract:

Objective    To evaluate the relationship between the injury time of traumatic discolored tooth and the efficacy of intracoronal bleaching. Methods    Choose 90 cases of maxillary incisor discoloration caused by trauma （90 teeth）. The colorimetric method was used to evaluate the changes of the color of the maxillary central incisors before and after the treatment for the discolored teeth by using Olympus Crystalege spectrophotometer. Observe the effect of bleaching treatment in different regions and the average number of visits due to discolored teeth at different time of injury. Results       The impact of duration of trauma on the tooth crown discoloration was not big，and there was no statistically significant difference （P > 0.05）. The appointment number of patients with different injury time was statistically different （P < 0.05）. On 1st and 5th visit，the effectiveness rate of body 1/3 and incisal sites 1/3 were higher than that of cervical 1/3，the difference being statistically significant（P < 0.05）；in body and incisal sites the effect differences had no statistical significance（P > 0.05）. Conclusion    Injury time traumatic discolored teeth is not related to the degree of the tooth crown discoloration. The longer the time of injury，the more the number of return visits. In trauma discolored teeth，the effective of intracoronal bleaching in body 1/3 and incisal sites 1/3 is better than that of cervical 1/3.

Key words: traumatic discolored teeth, coronal bleaching, time of injury, colorimeter

摘要：

目的    评价外伤变色牙受伤时间与冠内漂白治疗效果的关系。方法    选择2014年12月至2015年10月在中国医科大学口腔医学院口腔急诊·黏膜病科就诊的因外伤导致上颌中切牙变色患者90例（患牙90颗），采用冠内漂白技术治疗，应用Olympus Crystalege分光光度计型全牙比色仪分别对变色牙的颈1/3、中1/3、切1/3区域进行治疗前后的比色，观察比较各区域漂白效果及不同受伤时间变色牙的复诊次数。 结果    外伤变色牙受伤时间的长短对牙冠变色程度影响不大，差异无统计学意义（P > 0.05）。不同受伤时间患者的复诊次数差异有统计学意义（P < 0.05）。第1次和第5次复诊时，外伤变色牙的冠内漂白治疗有效率在中1/3和切1/3均明显高于颈1/3，差异有统计学意义（均P < 0.05）；而在中1/3与切1/3的有效率差异均无统计学意义（均P > 0.05）。结论    外伤变色牙受伤时间与牙冠变色的深浅不相关。外伤变色牙受伤时间越长，达到与邻牙颜色一致所需的复诊漂白次数越多。外伤变色牙的中1/3和切1/3区域的漂白效果优于颈1/3。

关键词: 外伤变色牙, 冠内漂白, 受伤时间, 比色仪