Two or three years. According to the 2023 enrollment brochure for in-service postgraduate students in stomatology, the in-service postgraduate courses in stomatology are equally qualified to apply for the exam. After entering school, they will take exams and attend classes in their spare time. Accordingly, Shen Shuo can get a master's degree certificate if he succeeds. In 2023, the enrollment institutions include Jinzhou Medical University, Zhengzhou University, Dalian University and Jilin University, of which Jilin University has a three-year academic system and others have a two-year academic system.