Received: 24 October 2018
Accepted: 28 December 2018
First Online: 12 January 2019
Ethics approval and consent to participate
: This study was approved by the ethics Committee at the Aichi Gakuin University School of Dentistry (Approval No. 463) and was resgisterd in advance as a clinical trial in the UMIN-CTR (Registration No. UMIN000024763). Written informed consent was obtained from the parents of the patients included in this study.
: Not applicable.
: The authors declare that they have no competing interests.
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