Abstract:

Objectives

To correct gummy smile of the patients with anterior alveolar vertical excess by using mini-implant anchorage.

Methods

Sixteen patients with gummy smile due to anterior alveolar excess were chosen for this clinical study. Mini-implants were implanted between the lateral incisor and the canine， and 100 g force was applied to intrude the upper anterior teeth. Records，including models， lateral cephalograms， periapical X-ray films and photos of the lowest one third of smile face， were taken before and after the treatment. Gingival exposure， gingival sulcus depth， clinical crown length and root absorption were also measured. All experimental data were collected and statistical analysis was performed.

Results

（1） The gingival exposure was decreased （2.3±0.5） mm， ranging from 1.8 to 3.1 mm. （2） The cephalometric analysis showed that the resistance center point of the upper central incisor was intruded （2.6±0.3） mm， the overbite was reduced （2.8±0.6） mm， the distance between the edge and the palate plane was decreased （3.1±0.7） mm， and the nasolabial angle was increased（5.4±2.9）° （P ＜0.05）. （3） The clinical crowns of anterior teeth were significantly reduced， but there was no obvious root absorption.

Conclusions

Gummy smile can be corrected by intruding upper anterior teeth with mini-implant anchorage. However， the gingival reconstruction lags behind the intrusion of upper anterior teeth at the same processing time.

Key words: Gummy smile, Mini-implant anchorage, Intrusion