Application to the dental treatment of free electron laser

本文研究了自由电子激光发射的超短脉冲对牛牙本质蒸腾的影响，并用高速摄像机观察了与Er：μ激光(2.94μm)波长相同的自由电子激光对牛牙本质蒸腾的影响。用扫描电子显微镜(SEM)观察了喷发出的蒸腾颗粒，并与Er：YAG激光测量的蒸腾深度进行了比较。此外，在2.50、2.94、3.50和4.00μm的自由电子激光照射波长下对牛牙本质进行照射，测量蒸腾深度，并用辐射温度计测量受照部位(受照一侧)和受照部位正下方样品的对侧(牙髓侧)的温度升高。结果表明，激光可以有效地消融牙本质，激光脉冲宽度小于热弛豫时间，激光波长约为2.94μm。

The present study focused on the effect of ultrashort pulses emitted by a FEL, and a high-speed camera was used to observe the aspects of bovine dentin transpiration using the FEL tuned to the same wavelength as Er:YAG laser (2.94μm). The ejected transpiration particles were also observed by a scanning electron microscope (SEM) and the depth of transpiration was compared with that obtained by an Er:YAG laser. Additionally, irradiation was performed on bovine dentin with varying FEL irradiation wavelengths of 2.50, 2.94, 3.50, and 4.00μm, the depth of transpiration was measured, and increases in temperature at the irradiated site (irradiated side) and the opposite side of the sample directly under the irradiated site (dental pulp side) were also measured by a radiation thermometer. The results showed that dentin could be ablated effectively by using a laset, having a pulse width shorter than the thermal relaxation time and an approximate wavelength of 2.94μm.