Objective To explore the risk factors of abutment edge exposure after implant restoration in the aesthetic area of anterior teeth, and provide a theoretical basis for aesthetic restoration of anterior teeth.

Methods A total of 108 patients with missing teeth in the anterior teeth area who had undergone implant restoration, involving 115 teeth, were reviewed. The collected data mainly included the causes of tooth loss, time of tooth loss, gingival biotype, depth of implant placement and thickness of alveolar bone on the lip and palate side. The patients were divided into the exposed group and unexposed group based on whether the edge of the restorative abutment was exposed at the gingival margin. The risk factors of edge exposure of the restorative abutment were analyzed.

Results After the restoration of 115 dental implants, the abutment edges were exposed in 19 cases and not exposed in 96 cases. There were statistically significant differences in the history of trauma, duration of tooth loss, gingival biotype and thickness of alveolar bone on the labial and palatine sides between exposure and non-exposure (P ＜ 0.01), while there was no statistical significance in the depth of implant implantation between exposure and non-exposure (P ＞ 0.05). The results of logistic regression analysis showed that the tooth loss time ＞ 1 year, history of dental trauma, thin gingival biotype and 4 mm ≤ thickness of the alveolar bone on the labial and palatal sides ＜ 7 mm were the independent risk factors of exposure of the abutment edge after implant surgery (P ＜ 0.05 to P ＜ 0.01).

Conclusions The reasons of tooth loss, duration of tooth loss, gingival phenotype, height and thickness of remaining bone were fully considered in anterior aesthetic zone implant restoration to reduce the aesthetic risk of implant restoration.