Funding for this research was provided by:
Japan Society for the Promotion of Science (26861648)
Received: 7 November 2018
Accepted: 23 January 2019
First Online: 26 March 2019
Ethics approval and consent to participate
: The study protocol was approved by Kyushu Dental University ethics committee (approval number 13-3) and followed the guidelines of the amended Declaration of Helsinki. All participants provided written informed consent to participate in the study.
: All participants consented to publication of their data via a written consent form obtained from the Kyushu Dental University ethics committee.
: Toru Maeda, Taro Mukaibo, Chihiro Masaki, Sirapat Thongpoung, Shintaro Tsuka, Akiko Tamura, Fumiko Aonuma, Yusuke Kondo, and Ryuji Hosokawa declare that they have no competing interests.
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