Abstract: Objective: To discuss cone beam computed tomography (CBCT) guided step-by-step traction of labial transposition of maxillary canine and lateral incisor. Methods: Twenty-two teenagers (26 canines) who visited Affiliated Stomatological Hospital of Nanjing Medical University for treatment of labial transposition of maxillary canine and lateral incisor were selected. CBCT was taken before treatment. Canines were divided into 5 groups and treatment was simulated. Results: Nineteen canines belonged to class Ⅰ, Ⅱ, Ⅲ and part of Ⅳ were successfully draged. Three canines belonged to class Ⅳ or class Ⅴ replaced the extracted incisors. Two canines belonged to class Ⅳ maintained the position, and 2 canine belonged to class Ⅴ canines were extracted. Conclusion: Classifying maxillary labial transposed canine with CBCT can guide the treatment plan, therefore improve the success rate of treatment.

Key words: Canine, Lateral , Incisor, Transposition, Step by step traction, CBCT