Abstract: Complicated crown-root fracture is a kind of severe traumatic tooth injury, and its fracture line is often located subgingival, which brings difficulties to the treatment. Combined with flap surgery, the broken line can be fully exposed, with clear vision, good moisture isolation effect, and other advantages. In this paper, we report a case of permanent central incisor with complicated crown-root fracture assisted by flap surgery, and summarize the indications, advantages, and disadvantages of the treatment methods for complicated crown-root fracture.

Key words: complicated crown-root fracture, flap surgery, dental trauma, fragment reattachment