Text and Data Mining valid from 2018-08-02
Received: 7 April 2018
Accepted: 2 June 2018
First Online: 2 August 2018
Ethics approval and consent to participate
: This research is a retrospective study, and ethical approval is not applicable for this study. However, ethical approval with the number of 95A11181 was obtained from the Tehran Dental Branch, Craniomaxillofacial Research Center, Islamic Azad University, Tehran.
: The authors declare that they have no competing interests.
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