Funding for this research was provided by:
Japan Society for the Promotion of Science (15K14423, 26463175, 16K07205)
School of Dentistry, Nihon University (Sato Fund)
Text and Data Mining valid from 2018-07-31
Received: 19 September 2017
Accepted: 16 July 2018
First Online: 31 July 2018
Ethics approval and consent to participate
: All participating subjects understood the nature of the research project and provided written, informed consent. Permission for this study was obtained from the Ethics Committee for Clinical Research of Fukuoka Dental College and Fukuoka College of Health Sciences (approval numbers 89, 233, and 249). All the study methods were carried out in accordance with the approved guidelines.
: Not applicable.
: The authors declare that they have no competing interests.
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