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Clinical standards for establishing facial balance and harmony in lingual orthodontics



ŸIntroduction
Facial balance and harmony has been perceived somewhat differently between Japan and Western countries. Under the influence of Buddhism introduced from India and the Chinese thought Confucianism, the Japanese have taken things as they stand. Thus, beauty has been thought to exist in the mind of the beholder rather than something that is definable with specific components. Indeed, high canine and protruded teeth are accepted as charming, and personalities with a malocclusion are still appearing on television and mass media in Japan, one of the most economically advanced nations (Fig. 1).

Fig-1 Actress & Comedian


ŸIntroduction-2
Historically, however, there were Japanese artists who created beauty from its components based on a certain rule. Among the ukiyoe artists in the Edo period who had an influence on Gogh, Cezanne, Monet, etc., those who had a clear idea of proportion were Kiyonaga, a beauty painter, and Hokusai, a landscape painter (Fig. 2, 3).
Clearly, the composition of Hokusai KatsushikaÕs famous landscape The Great Wave off Kanagawa from Thirty-six Views of Mt. Fuji is based on the golden section.

Fig-2

Fig-3

Fig-4

Fig-5


ŸGolden section
(Fig-6) The Great Wave off Kanagawa from Thirty-six Views of Mt. Fuji. 1831


ŸConsiderations in creating facial balance and esthetics
Harmony and symmetry are considered to be basic components of beauty and comprise an ideal facial profile. Beauty is difficult to quantify, and yet attempts have been made to establish numerical norms by measuring facial contours
and locations of facial structures
relative to reference lines in
millimeters and degrees.
Among the factors to be
taken into consideration in
achieving an esthetic facial
profile are age, gender,body
type, hair,race, symmetry
and harmony.
Fig-7 THE BALANCE OF THE SMILE


ŸConsiderations in creating facial balance and esthetics-2
Particularly, the forehead,eyes, nose, lips and chin are regarded as the 5 major components of a beautiful face.
Orthodontists have been discussing facial esthetic improvement. The four treatment objectives proposed by Tweed are well known: 1) the best balance and harmony of the facial line, 2) post-treatment stability of the dentition, 3) healthy oral tissues, and 4) effective chewing function. There have been increasing demands for beautiful facial profile and straight teeth and white teeth among young individuals (Fig. 7).


ŸPurpose and subjects of the study
This purpose of this study was to obtain clinical standards for facial balance and harmony by analyzing before and after lateral cephalograms of female patients treated by lingual orthodontics.

1: A total of 23 adult female patients who underwent lingual orthodontic treatment of both the upper and lower arches.
2: The same operator placed the Kurz 7th lingual appliance by indirect bonding technique using C.L.A.S.S. (Custom Lingual Application Set-up System) in all the subjects.


ŸPurpose and subjects of the study-2
3: Angle Class II div. 1 or bimaxillary protrusion cases were included based on the initial morphologic examinations. The study excluded patients with mandibular prognathism (anterior crossbite) requiring a different treatment mechanics and those with skeletal open bite or cleft lip and palate associated with severe mentalis strain upon lip closure.
4: All the subjects were treated by four bicuspid extraction. Non-extraction cases were excluded.
5: Level Anchorage System was used for diagnosis and treatment planning. Treatment was performed according to the step-by-step method proposed by Gorman, J.C.
6: The lateral cephalograms of the 23 subjects before and after treatment were used as study materials.


ŸMaterial
The subjects were divided into Straight Group (S Group) with upper lip to E-line being smaller than the average of 0.5mm and hence a satisfactory profile and Convex Group (C Group) with an unfavorable upper lip to E-line value of greater than 0.5mm.
One representative case each from S Group and C Group is shown (Fig. 11-14). Several cases selected from the study subjects are also displayed on the table.


ŸMethod
Cephalometric analysis was made of pre- and post-treatment lateral cephalograms of the 23 adult female patients treated with four bicuspid extraction and lingual orthodontics in order to evaluate alveolar and other hard tissue changes and associated soft tissue (profile) changes.
The analysis included 17 Steiner measurements (Fig. 8),
4 Tweed measurements (Fig. 8), 4 Powell measurements (Fig. 9) and 4 of the soft tissue measurements proposed by Yamawaki, et al.