Department of Prosthodontics, Bezmialem Vakıf University Faculty of Dentistry, Adnan Menderes Bulvarı Vatan Caddesi, 34093, Istanbul, Turkey,
Lasers Med Sci. 2015 Feb;30(2):577-82. doi: 10.1007/s10103-013-1375-5. Epub 2013 Jun 21.
The aim of this study was to evaluate the increase in temperature induced by various light sources during in-office bleaching treatment, under simulated blood microcirculation in pulp conditions. Ten freshly extracted human maxillary central incisors were used for the study. The roots of the teeth were removed from approximately 2 mm below the cementoenamel junction and fixed on an apparatus for the simulation of blood microcirculation in pulp. A J-type thermocouple wire was inserted into the pulp chamber through an artificial access at the lingual surfaces of the teeth, and another thermocouple wire was fixed on the labial surface of the teeth meanwhile. An in-office bleaching agent, intense red in color and with 30% water content, was applied to the labial surfaces of the teeth, and repeating measurements were made for each tooth using three different light sources: Er:YAG laser (40 mJ, 10 Hz, 20 s), 810-nm diode laser (4 W, 20 s, CW), and high-intensity light-emitting diodes (LED) (1,100 mW/cm(2), 20 s) as the control. Temperature increase in the pulp chamber and within the bleaching gel during light application were recorded and statistically evaluated. The highest pulp temperature increases were recorded for the diode laser group (2.61 °C), followed by the Er:YAG laser (1.86 °C) and LED (1.02 °C) groups (p < 0.05; analysis of variance (ANOVA), Tukey's honestly significant difference (HSD)). Contradictorily, the lowest gel temperature increases were recorded for diode laser (6.21 °C) and followed by LED (12.38 °C) and Er:YAG (20.11 °C) groups (p < 0.05; ANOVA, Tukey's HSD). Despite the significant differences among the groups, the temperature increases recorded for all groups were below the critical value of 5.6 °C that can cause irreversible harmful changes in pulp tissue. It can be concluded that, with regard to temperature increase, all the light sources evaluated in this study can be used safely for in-office bleaching treatment within the described parameters.
本研究旨在评估在模拟牙髓血循环条件下，各种光源在诊室漂白治疗过程中引起的温度升高。使用 10 颗新鲜离体上颌中切牙进行研究。牙齿的根尖从牙釉牙骨质界下方约 2mm 处切除，并固定在牙髓血循环模拟装置上。一根 J 型热电偶线通过牙齿舌面的人工入口插入牙髓腔，同时另一根热电偶线固定在牙齿的唇面。将一种颜色鲜红、含水量为 30%的诊室漂白剂应用于牙齿的唇面，对每颗牙齿重复测量，使用三种不同的光源：铒：钇铝石榴石（Er:YAG）激光（40mJ，10Hz，20s）、810nm 二极管激光（4W，20s，CW）和高亮度发光二极管（LED）（1100mW/cm²，20s）作为对照。记录并统计分析光应用过程中牙髓腔和漂白凝胶内的温度升高。二极管激光组的牙髓温度升高最高（2.61°C），其次是 Er:YAG 激光组（1.86°C）和 LED 组（1.02°C）（p<0.05；方差分析（ANOVA），Tukey Honestly Significant Difference（HSD））。相反，二极管激光组的凝胶温度升高最低（6.21°C），其次是 LED 组（12.38°C）和 Er:YAG 组（20.11°C）（p<0.05；ANOVA，Tukey HSD）。尽管各组之间存在显著差异，但所有组记录的温度升高均低于可导致牙髓组织不可逆性有害变化的临界值 5.6°C。可以得出结论，就温度升高而言，在本研究中评估的所有光源都可以在描述的参数范围内安全地用于诊室漂白治疗。
