Received: 31 October 2018
Revised: 8 January 2019
Accepted: 25 February 2019
First Online: 12 March 2019
Ethics approval and consent to participate
: All human stem cells involved in the present research followed the International Society for Stem Cell Research “Guidelines for the Conduct of Human Embryonic Stem Cell Research.” The study was approved by the Ethical Committee of Beijing Stomatological Hospital (Review No. 2011–02) before the study started. Written informed consent was obtained from each patient, under the approved guidelines set by Beijing Stomatological Hospital, School of Stomatology, Capital Medical University.
: Not applicable.
: The authors declare that they have no competing interests.
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