Funding for this research was provided by:
Key research and development projects in Hebei province (18277776D)
Project supported by government for cultivating excellent talents in clinical medicine (2019061441-2)
Article History
Received: 29 February 2020
Accepted: 21 October 2020
First Online: 2 November 2020
Compliance with ethical standards
:
: The authors declare that they have no conflicts of interest.
: This study was performed in line with the principles of the Declaration of Helsinki and has been approved by Medical Ethics Committee of Hospital of Stomatology, Hebei Medical University.
: Both written and verbal informed consent were obtained from every participant.