Title {1}	Efficacy and safety of piezocision in accelerating maxillary anterior teeth en-masse retraction: study protocol for a randomized controlled trial
Trial registration {2a and 2b}.	Registry name: Accelerate orthodontic tooth movement by piezocision assisted orthodontics: a randomized controlled trial Trial identifier: ChiCTR1900024297
Protocol version {3}	Version 2.0 Issue date: 22 April 2019
Funding {4}	This trial was funded by the Science and Technology Commission of Shanghai Municipality (grant number 19411961900 and 20Y11904100), Shanghai Hospital Development Center (grant number SHDC12019126).
Author details {5a}	1Department of Orthodontics, Shanghai Stomatological Hospital & School of Stomatology, Fudan University 2Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Fudan University 3Department of Pediatric Dentistry, Shanghai Stomatological Hospital & School of Stomatology, Fudan University
Name and contact information for the trial sponsor {5b}	1. Science and Technology Commission of Shanghai Municipality. Address: 200 People Avenue, Shanghai, China. Tel:(8621)-23111111 2. Shanghai Hospital Development Center. Address: No.2 Kangding Road, Shanghai, China. Tel:(8621)-96886
Role of sponsor {5c}	The funding sponsors will not participate in any procedures of the clinical trial, including study design, execution, data collection and statistical analysis.