Improvement of orthognathic surgical techniques make it possible to design esthetic surgical correction for total esthetic face.
In order to find the esthetic line which guide esthetic surgical correction in patients of orthognathic surgery, cephalometric soft tissue analysis of esthetic faces were performed. In esthetic Korean young adults, 25 males and 25 females who
were
within 1 S. D. of E-line, ANB, P/A facial height ratio, were analyzed in natural position keeping their face eye level.
1. Sn position is constant in males and females. The Sn-N1-N1 Vertical plane angle is 5.3° in both sexes. Sn is positioned in front of 5 mm in female 7 mm in male from the N1 vertical plane.
2. The Sn-Ls line make constant angle to horizontal plane with 72.5° in both sexes, which is called "upper esthetic line". The L-Pg?line makes constant angle to 72.4° (range 72.2° in female to 72.6° in male), which is calle d"lower esthetic
line".
3. When inter-esthetic line angle (the Sn-Ls line to Ls-Pg?line) has 144.9°, lowr thired face has esthetic upper and lower lip.
4. In treatment planning, Sn is first corrected in proper position, and then upper and lower esthetic line ae established with the angle of 144.9. The maxilla is moved to tangent Ls to the upper esthetic line, and mandible is moved to tangent Li
and
Pg?to the lower esthetic line, according to the "y"-shaped esthetic lines, then lower third face showes esthetics.
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