Abstract: The ablation effect of laser radiation on biological tissue enables cutting and grinding of hard tissues likes teeth, which demonstrates unique advantages compared to traditional surgical instruments such as piezosurgery or high speed airturbine. This article provides an overview of the research progress on dental laser ablation characteristics, focusing on the relationship between ablation effect and laser parameters such as wavelength, pulse width and energy. It is shown that when the laser wavelength matches well with the absorption wavelength of tissue, the laser ablation rate can be improved and the thermal damage can be reduced. Therefore, selecting wavelength with high absorption coefficient of water and hydroxyapatite, the main components of dental tissue , will achieve better ablation results. Under the same energy and wavelength conditions, in order to achieve good ablation results, the pulse duration of the laser should roughly match the thermal relaxation time of dental tissue, and a longer pulse duration will cause heat accumulation, leading to thermal damage of surrounding tissues. It shows that when nanosecond lasers are used for ablation, there is no smear layer, and the dentinal tubules remain open, which has high surgical safety. As for pulse energy of lasers, it shows that increasing the single pulse energy may enhance the ablation rate in the initial stage, but at higher energy levels, a clear saturation effect occurs due to the obstructive effect of ablation products. In summary, laser ablation technology has unique advantages, such as good compatibility, high precision, ability to achieve complex cutting. It can reduce the vibration, bone debris and wear caused by traditional instruments during surgery, effectively alleviating the discomfortable of patient and greatly enhancing the speed, safety and comfort of surgery. This article comprehensively reviews and the potential relationship between laser parameters (wavelength, pulse width and energy) and ablation effects, providing a reference for the optimal combination of laser parameters.

Key words: laser techniques, laser medical, dental tissue ablation, irradiation parameters