1. School of Stomatology, Shandong University, Wen Hua Xi Lu, Jinan City 250012, Shandong Province, China
2. Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Wen Hua Xi Lu, Jinan City 250012, Shandong Province, China
3. Department of Stomatology, Jinan Military General Hospital, Shi Fan Lu, Jinan City 250031, Shandong Province, China
4. Center for Stem Cells and Regenerative Medicine, The Affiliated Liaocheng Hospital, Taishan Medical University, 252000, Shandong Province, China