Abstract
r the initial reports of the effects of Er: YAG laser on dental hard tissue by Keller and Hibst, the Er: YAG laser has been recognized as a new tool developed for cavity preparation. The Er: YAG laser has a wavelength of 2.94μm and, by virtue of its highly efficient absorption in water, can efficiently ablate dental hard tissue with almost no thermal effect on the pulp. Moreover, the Er: YAG laser produces minimal vibration and noise during cavity preparation and the need for local anesthesia is none or minimal, so the Er: YAG laser does not cause a fear or discomfort to the patient in comparison to the conventional methods of cavity preparation. Futhermore, the patient feels less pain or none during laser ablation of dental hard tissue. However, it takes time to master the practical skill of Er: YAG laser irradiation on dental hard tissue, because it is difficult to control the power of the Er: YAG laser to ensure efficient ablation without side effects, cracking of tooth substance, heat damage to the pulp or causing pain to the patient. Moreover, both the method and mode of irradiation are very different for each type of Er: YAG laser apparatus. Therefore, training on irradiation skills based on the results of practical laser treatment is needed when applying the Er: YAG laser on dental hard tissue, and skills should be improved together with the development of Er: YAG laser apparatus.
