Abstract: Objective To observe the clinical effect of anterior incisional margin or angle defects repaired with resin on enamel shoulder．Methods A total of anterior teeth with different degrees were selected from 2017/9 to 2018/4. 98 anterior teeth in 60 patients were randomly divided into 2 groups, 49 teeth in each group. In the experimental group, the teeth were repaired by resin after preparation of enamel shoulder. And the control group was restored by resin after preparation of enamel short bevel. The restoration rates of two groups were observed and compared after 3-month, 6-month and 1-year follow-up. Results After 3 months, the difference in the repair success rate between the experiment group and the control group had no statistical significance (P>0.05). The repair expulsion rates in the control group were obviously higher than those in the experiment group after 6-month and 1-year follow-up, and the differences had statistical significance (P<0.05). Conclusion The clinical efficacy of restoring anterior incisional margin or angle defects by resin after preparation of enamel shoulder can lower tooth injury and postoperative complications．

Key words: Enamel shoulder, Anterior teeth, Resin filling, Aesthetic restoration