Several types of lasers have been developed and tried to be clinically applied to the oral area. Lasers have been used for various clinical practices, diagnosis and prevention of dental caries, treatment for periodontal disease, hypersensitive dentin, relieving pain, and root canal infections. The Er:YAG laser is the only dental laser that has the potential to ablate both dental hard tissue and soft tissue. In this report, I introduce the practical procedure of some cases using the Er:YAG laser, and discuss the utility of Er:YAG laser application on oral soft tissue or hard tissue
