Evaluation of vital tooth breaching with hydrogen peroxide more than 3O%

本研究旨在探讨牙齿美白剂使用后，过氧化物对牙齿的影响。用磷酸盐缓冲液充填人切牙冠制备人工根管。根据说明书使用含有30%过氧化氢或35%过氧化脲的牙齿增白剂，进行或不进行酸蚀预处理。使用鲁米诺化学发光法测量渗入根管内缓冲液的过氧化物量。渗透过氧化氢量范围为7 μ M至100.5 μ M。过氧化氢应用组的渗透量约为脲应用组的1.6倍。酸蚀预处理组的渗透量超过未预处理组的约4倍。一种含过氧化氢的增白剂，由液体和粉末组成。用电子探针对增白剂的粉末成分进行了定性分析，结果表明，增白剂中含有Fe和Cu离子。这一发现表明增白剂通过过氧化氢本身或与Fe或Cu离子产生的氧自由基对牙齿产生影响。因此，这些发现表明，漂白剂中的过氧化物渗透到牙齿表面可能会导致美白治疗后的一些不适。

This research was to clarify the effects of peroxide on teeth after the tooth-whitener-application. An artificial root canal was prepared using the crown of human incisors filled with phosphate buffer solution. Tooth-whitener containing 30% hydrogen peroxide or 35% carbamide peroxide was applied according to the instructions with or without acid-etching pretreatment. Luminol-chemi luminescence was used to measure the quantity of peroxide that penetrated into the buffer within the root canal. The penetrated peroxide quantity ranged from 7 μ M to 100.5 μ M. The penetration quantity for the hydrogen peroxide-applied group was about 1.6-fold greater than that for the carbamide-applied group. The penetration quantity for the acid-etching pretreatment group exceeded about 4-fold greater than that of the non-pretreatment group. The whitener containing hydrogen peroxide consists of liquid and powder. Qualitative analysis of powder component of the whitener with EPMA showed that it contained Fe and Cu ions. This finding suggests that whitener affects on the tooth by means of hydrogen peroxide itself or the oxygen radical that generated with Fe or Cu ion. Hence, these findings suggest that the penetration of peroxide from whitener applied to the tooth surface might cause some discomfort after whitening treatment.