Erbium:YAG and holmium:YAG laser root resection of extracted human teeth

Root resection of extracted human teeth was performed using the erbium:YAG (Er:YAG) and holmium:YAG (Ho:YAG) laser to investigate the clinical application of lasers on hard tissue. The CO2 laser and the mechanical drill were also used for comparison. After resection using these technologies, the morphological changes of the cut surface were investigated by optical and scanning electron microscope. Er:YAG laser irradiation produced smooth, clean resected surfaces without signs of thermal damages. Complete obturation of the root canal was maintained after Er:YAG laser irradiation. Ho:YAG laser irradiation, however, produced some signs of thermal damage. Relatively large voids between the gutta-percha and the canal walls were revealed after Ho:YAG laser irradiation. The sealing of the dentinal tubules was not completely attained as stipulated by original conditions of this study.