Funding for this research was provided by:
National Natural Science Foundation of China (81870798, 81400551, 81704128)
Fundamental Research Funds for the Central Universities (xjj2017097)
Innovation project of science and technology of Shaanxi province (2016KTCL03-10)
Xi’an science and technology planning project (201805100YX8SF34-3)
Youth Research Fund from College of Medicine & Hospital of Stomatology, Xi’an Jiaotong University (201705)
Text and Data Mining valid from 2019-05-02
Received: 5 November 2018
Accepted: 16 April 2019
First Online: 2 May 2019
Ethics approval and consent to participate
: The present study was approved by the Ethics Committee of College of Medicine & Hospital of Stomatology, Xi’an Jiaotong University. All patients or their parents have signed the informed consent form.
: Not applicable.
: The authors declare that they have no competing interests.
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