Maxillary Sagittal Position in Relation to the Forehead: A Target for Orthognathic Surgery.

Abstract

The relationship of the maxillary incisor to forehead position and angulation may be a predictor for the esthetic antero-posterior maxillary position in orthognathic surgery, but this has not been fully explored in the existing literature. Additionally, this analysis requires a lateral smiling photograph, which is not typically included in orthodontic/orthognathic records. This is a bidirectional study of Caucasian orthodontic patients with malocclusions correctable with nonsurgical and nonextraction treatment. Subjects for Group 1 were enrolled prospectively and records included a lateral smiling photograph. Group 2 patients were collected retrospectively with standard records. The analysis described in Andrews' Element II of The Six Elements of Orofacial Harmony was applied to the smiling photographs for Group 1, resulting in "Incisor- goal anterior limit line (GALL)" measurements. A modified analysis utilizing cephalometric tracings was applied for both the groups, and the results were compared. Forty-nine subjects with mean age 11.8 ± 1.2 years were included (n = 14 for Group 1, n = 35 for Group 2). Mean Incisor-GALL distances were 3.71 ± 5.39 mm for females and 4.47 ± 5.06 mm for males. Correlation between analyses was excellent (intraclass correlation coefficient = 0.872). In conclusion, a modified approach to measuring the Incisor-GALL distance using standard orthodontic records correlated closely with the analysis described by Andrews. Normal values for this measurement are presented for Caucasian patients.