Text and Data Mining valid from 2018-04-02
Received: 18 December 2017
Accepted: 8 March 2018
First Online: 2 April 2018
: MT, DDS, PhD is a research assistant. VP, DDS is a PhD student. PC, MD, DDS, MS is a professor and department chair. CC, MD, DDS, MS is a professor.
: The study was performed in accordance with the Declaration of Helsinki. It is a retrospective analysis, and the protocol was approved by the Chairman of the Section of Orthodontics, Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila.
: Not applicable.
: The authors declare that they have no competing interests.
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