Abstract: Provided are a dental apparatus and a dental system using the dental apparatus, the dental apparatus including a signal detector configured to detect an electrical signal varying according to a distance between a file inserted into a tooth and an apical foramen, and a controller configured to execute a first mode for calculating the distance between the apical foramen and the file by using the electrical signal and for displaying the distance on a screen, and configured to execute a second mode for displaying root canal working length information and identification information received through a communication part or input part, on the screen, for generating identified root canal working length information by using the root canal working length information and the identification information, and for transmitting the identified root canal working length information to the external device through the communication part according to the input signal.