Abstract: Objective: To explore the establishment of the incisor extraction wound models in aesthetic area of the rats and the application effect of modified minimally invasive tooth extraction surgery, and to provide the basis for establishment of the incisor extraction wound models in aesthetic area and improvement of the healing of alveolar bone and soft tissue. Methods: Twenty-four SD rats were randomly divided into control group and experiment group (n=12). The crowns of right lower incisors of the rats were removed along with the top of gingival tissue on the 9th, 6th and 3rd days before the incisors extraction, and then the incisor were extracted on the 10th day of experimental modeling. In experiment group, the incisors of rats were extracted by the modified minimally invasive incisor extraction, while in control group the conventional extraction was used to extract the incisor of the rats. The survival rates and body weights of the rats in two groups were observed before and after the incisor extraction. The complete degrees of incisor extraction of the rats in two groups were detected,and the rates of complete incisor extraction were calculated; the healing condition of soft tissue around the incisor extraction of the rats in two groups 1 week after incisor extraction and the recovery condition of mandibular alveolar bone of the rats 4 weeks after incisor extraction were compared. Results: The survival rate of the rats in experiment group was higher than that in control group (P<0.05). The body weights of the rats in experiment group at different time points after extraction were higher than those in control group (P<0.05). Compared with control group, the rate of complete incisor extration of the rats in experiment group was increased(P<0.01).The soft tissue around the incisor extraction wound of the rats in experiment group was completely healed within one week after incisor extraction, and new bone was found at the top of alveolar ridge four weeks after incisor extraction; meanwhile, the soft tissue around the incisor extraction wound of the rats in control group was still red and swollen one week after incisor extraction, and the trabecular structure of bone at the top of alveolar ridge was disordered found weeks after incisor extracion, and the new bone structure was poor. Conclusion: The modified minimally invasive tooth extraction surgery can significantly improve the complete extraction effect of incisors in the rats, and the soft tissue around the incisor extraction wound and the alveolar bone are healed well after minimally invasive tooth extraction.

Key words: extraction wound in aesthetic area, minimally invasive extraction, soft tissue healing, alveolar bone