Kajii, Takashi S.
Sakaguchi, Yui
Sawa, Yoshihiko
Tamaoki, Sachio
Article History
Received: 21 September 2018
Accepted: 28 November 2018
First Online: 14 January 2019
Ethics approval and consent to participate
: The Ethics Committee of Fukuoka Dental College approved the protocols of this retrospective study (No. 214). Subjects provided their informed consent for participation in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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