An object of the invention is to provide a tightening apparatus for a dental implant capable of reducing the occurrence of slip phenomenon in a manual operation. The tightening apparatus includes a torque wrench (W) and a slip detection device (D). The torque wrench (W) includes a tightening part, a wrench body having a head (21) provided with the tightening part (10) and a handle (22), and a load cell (30) for detecting tightening torques. The slip detection device (D) includes a slip determiner (52) and a buzzer (93). The slip determiner (52) is adapted to sample an amount of change of the tightening torques in every predetermined time t, to sequentially compare the amount of change of the tightening torques in a prior predetermined period t with the amount of change of the tightening torque in a subsequent predetermined period t that is immediately after the prior predetermined period t, and to determine whether or not the latter amount of change is smaller than the former amount of change. The buzzer (93) notifies the tightening state is on the verge of slip phenomenon when the slip determiner (52) determines that the latter amount of change is smaller than the former amount of change.
