Abstract
The disadvantages of the current orthodontic treatment both before and after orthognathic surgery include a long treatment time and temporary worsening of facial appearance during the orthodontic treatment. The surgery-first approach (SFA) without presurgical orthodontic treatment shortens the treatment time drastically compared with using a conventional orthodontics-first approach. We hypothesized that the shortening of treatment time could be because of enhancement of bone metabolism after orthognathic surgery. We found that the regional acceleratory phenomenon (RAP) as well as systemic acceleratory phenomenon (SAP) occur after osteotomy, which would accelerate orthodontic tooth movement, resulting in the reduced treatment time in SFA patients.