Text and Data Mining valid from 2019-04-17
Received: 29 January 2018
Accepted: 31 March 2019
First Online: 17 April 2019
Compliance with ethical standards
: They were all informed about the study and signed a detailed informed consent form. Ethical approval for the study was obtained by the Committee of Research and Ethics of the Dental School, National and Kapodistrian University of Athens.
: The authors declare that they have no conflict of interest.