Dental caries in the early stages are painless but in the later stages can cause pain, both on the affected tooth and the area around the tooth. When the cavities and bacterial growth deepen on the enamel and dentine of the tooth, the pain appears occasionally and increasingly sharply. When bacterial growth has reached the pulp of the teeth composed of blood vessels and tooth nerves, then there is an infection of the pulp called pulpitis that will cause a very painful and pulsating. When cavities runs, the dentist will make a prosthesis as a tooth replacement that has been removed due to cavities or trauma. The making of this prosthesis should be as detailed as it may resemble the original tooth shape. Thus, dentists require accurate micromotor speed settings. Most dentists still use a micromotor that still uses a manual selector for motor speed selection and no rpm speed display required on the dental micromotor. Therefore, the authors modified the dental micromotor by adding the LCD to display the speed and direction of the micromotor rotation. In this dental modification micromotor has two rotation selection, that are turn right and turn left. The dorsal speed of the micromotor is displayed between 5000 - 25000 rpm with the increase of 5000. The right turn has a more stable error result than the left turn, but the 5000 rpm on the right turn error is too high at 1.7% and the left turn is only 0.1%. On the right and left rotation both have the smallest error value at 25000 rpm rotation is 0.02% and 0.05%.