1. Laboratory of Molecular Signaling and Stem Cells Therapy, Beijing Key Laboratory of Tooth Regeneration and Function ReconstructionCapital Medical University School of Stomatology No. 4 Tiantanxili, Dongcheng District Beijing 100050 China
2. Department of Endodontics, Beijing Stomatological Hospital, School of StomatologyCapital Medical University No. 4 Tiantanxili, Dongcheng District Beijing 100050 China
3. Department of Stomatology, Beijing Friendship HospitalCapital Medical University Beijing 100050 China