A device is provided for opening mouth. The device is custom-made through 3-dimensional (3D) printing. The overall framework is printed out after 3D-scanning the oral cavity, which meets a patient's oral shape. The present invention practically and effectively fabricates a custom-made mouth-opening device. The mouth's structure changed after surgery is taken into consideration, so that the patient can easily open the mouth with one hand. Furthermore, because the weight overall is light, the whole single-hand operation feels no heavy. The prolonged work of dental rehabilitation required by the patient is met. The device is easy to be cleaned. The feature of high material strength yet with proper softness is achieved. The comfort of use is increased for the patient with life quality enhanced. The effectiveness of rehabilitation and intervention is improved. The cost of custom-made medical material is effectively reduced.
