研究了调Q Er:YAG激光消融离体牙本质过程中水雾的作用及其对消融后牙本质微结构的影响。调Q Er:YAG激光重复频率为3 Hz，脉冲宽度为62 ns，作用脉冲数为10，能量范围为4～70 mJ，水雾流量分别为0，4，9，13 mL/min时消融牙本质。每种实验条件下消融10个牙本质样品，利用扫描电镜观察消融坑洞微结构。实验结果表明，随着水雾流量的增加，调Q Er:YAG激光对人牙本质的消融阈值呈逐渐增加的趋势，牙本质所受机械损伤减小。实验结果对了解调Q Er:YAG激光消融牙硬组织的微观结构及牙科治疗应用具有参考价值。

The effect of water mist on the extracted dentin ablation by Q-switched Er:YAG laser is investigated, and the influence of water mist on the ablated dentin microstructure is studied. The Q-switched Er:YAG laser with 62 ns pulse width is used to ablate the human dentin at the repetition rate of 3 Hz, the number of pulses is 10, and the energy range is from 4 mJ to 70 mJ. Different flow rates of water mist (0, 4, 9, 13 mL/min) are applied during the experiments. 10 dentin samples are ablated under each experimental condition. A scanning electron microscope is used to observe the microstructures of ablated holes. The experiment result shows that the increase of flow rate of water mist makes the Q-switched Er:YAG laser ablation threshold to dentin rise, and the dentin is protected from mechanical damage. The results are guided for acquiring microstructures during dentin ablation with Q-switched Er:YAG laser and practical treatment in dentistry.