Abstract: Objective: To evaluate the application effects of gingival self-healing combined with platelet-rich fibrin(PRF) in the improved extraction site preservation. Methods: Twenty-one focus teeth from 21 patients who needed to extract maxillary residual crowns in esthetic zone were selected,and randomly divided into the observation group treated with gingival self-healing combined with PRF in the extraction site preservation,conventional group treated with conventional extraction site preservation surgery and blank control group treated with minimally invasive tooth extraction(7 cases in each group).The thickness from labial cervical bone plate to lingual cervical bone plate(H1),height from alveolar crest to mesial incisal edge of adjacent teeth(H2),height from alveolar crest to distal incisal edge of adjacent teeth(H3),bone density before tooth extraction(D1),bone density after 6 months of tooth extraction(D2),distance of buccal medial and distal gingival papilla to corresponding medial adjacent teeth incisor margin(H4 and H5) and vertical distance from the middle point of buccal gingival margin to extended line of mesial adjacent teeth incisal margin(H6) in the residual crowns in three groups were measured before tooth extraction and after 6 months of tooth extraction. Results: After 6 months of tooth extraction,the differences of H1-H6 and bone density among three groups were statistically significant(P<0.05 to P<0.01).After 6 months of tooth extraction,the H1-H3 and bone density in the observation group were obviously higher than those in conventional group and blank control group(P<0.05 to P<0.01). Conclusions: The gingival self-healing combined with PRF in the improved extraction site preservation can effectively preserve the width and height of the alveolar ridge,maintain the thickness of the gingival soft tissue,and play a good effect of closing the tooth extraction wound.