Provided are an electric motor that enables to achieve downsizing while securing performance, and a dental device that includes the electric motor. A brushless slotless electric motor 10 includes: a stator 3 that includes a stator core 301 and a plurality of coils 31 to 33, the plurality of coils 31 to 33 being disposed at an inside of the stator core 301 and a rotor 2 that includes a shaft 21 and a magnet 22, the rotor 2 being rotated around the shaft 21 with respect to the stator 3. The plurality of coils 31 to 33 are adjacent to each other in a rotation direction of the rotor 2 so as not to lap mutually. Lf < Lc is satisfied where Lf is a length of the stator core 301 in an axial direction and Lc is a length of the coil in the axial direction.
