A quantitative research on clinical parameters of gingival contour for anterior teeth esthetic analysis and design

To provide reference for computer-aided esthetic analysis and design of the maxillary anterior teeth.

Intraoral scanner was used to obtain the maxillary three-dimensional digital models of subjects with healthy periodontal tissue. In SpaceClaim, the occlusal plane was established as the horizontal reference plane to measure the positional relation between the gingival zenith (GZ) of the maxillary anterior teeth, the angle formed between the gingival line and the maxillary midline (GLA), the distance between the GZ of the lateral incisor and gingival line (LID), and the distance between the GZ and the vertical bisected middle surface along the long axis of the clinical crown (VBMS).

The GLA was 92.7 ± 3.2°. The GZ of the canine, lateral incisor, and left central incisor were located to the GZ of the right central incisor coronally at 0.68 ± 0.91, 0.65 ± 0.66 mm, and apically at 0.12 ± 0.42 mm, respectively. The LID was 0.65 ± 0.92 mm. The GZ of the canine, lateral incisor, and central incisor were located distally to the VBMS at 0.00 ± 0.06, 0.27 ± 0.19, and 0.73 ± 0.21 mm, respectively.

The GZ at different tooth position are in different heights. The direction and degree of the GZ deviation from the VBMS are also related to tooth position.

The clinical parameters of the gingival contour obtained in this research can be used for patients with unsound contour of periodontal soft tissue to do the anterior teeth esthetic analysis. Besides, it can also be used to determine the proper position between the GZs of the maxillary anterior teeth in anterior teeth esthetic design.