Abstract: Objective: To evaluate the effect of compression mold template and diagnose mock-up surgical template in the crown lengthening. Methods: Thirty patients who needed anterior crown lengthening were randomly divided into two groups. The compression mold group used compression mold guide template for 15 patients and 76 affected teeth, and the diagnose mock-up group used diagnostic mock-up surgical template for 15 patients and 80 affected teeth. 6 months and one year after surgery, the probing depth (PD), restoration margins to gingiva distance, the quality of restoration, and pink esthetic score (PES) were evaluated, and then statistical analysis. Results: The periodontal conditions of two groups were good after surgery, only one site PD of 5mm appeared on the adjacent surface of the compression mold group one year after surgery, and the remaining sites were less than 4mm. 6 months after surgery, two groups of restoration margins under 1 mm to 1 mm on the gingiva, differences between two groups was statistically significant (P<0.05). After one year, two groups of restoration margins under 2 mm to 1 mm on the gingiva, restoration margins to gingiva adjacent surface distance difference was statistically significant (P<0.05). There were more sites at the gingival margin level in the diagnose mock-up group. After surgery, grade C was not found in the prosthesis shape accuracy and edge closeness, grade A ratio in the diagnose mock-up group was higher than that in the compression mold group, and the difference was statistically significant (P<0.05). Grade A was found in the surface smoothness. After surgery, PES score of the compression mold group was lower than that of the diagnose mock-up group (P<0.05). Conclusion: The accuracy of the diagnose mock-up surgical template is relatively high, and the postoperative repair effect is more stable.

Key words: crown lengthening , surgical template