• The korean journal of orthodontics
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• v.35 no.3 s.110
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• pp.163-173
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• 2005

The purpose of this study was to compare the asymmetric degree between maxillofacial hard and soft tissues in individuals with facial asymmetry. Computerized tomographies (CT) of 34 adults (17 male, 17 female) who had facial asymmetry were taken. The CT images were transmitted to personal computers and then reconstructed into three-dimensional (3D) images through the use of computer software. In order to evaluate the degree of facial asymmetry, 6 measurements were constructed as the hard tissue measurements while 6 counterpart measurements were taken as the soft tissue measurements. The means and standard deviations were obtained for each measurement using 3D measure, then t-test was used to investigate the differences between each hard tissue measurement and the corresponding soft tissue measurement All measurements used in the present study showed statistically significant differences between the hard and soft tissues. The degree of soft tissue asymmetry was smaller than that of corresponding hard tissue asymmetry in case of chin deviation, frontal ramal inclination difference, and frontal corpus inclination difference. On the other hand, the degree of soft tissue asymmetry was greater than that of underlying hard tissue asymmetry in the measurement of lip canting and lip cheilion height difference The present study suggests that asymmetric differences of hard and soft tissue is observed nu facial asymmetric subjects and thus soft tissue analysis is needed in addition to hard tissue analysis when making an evaluation of facial asymmetry.

• The korean journal of orthodontics
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• v.38 no.4
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• pp.252-264
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• 2008

Objective: To aid the development of a frontal image simulating program, we evaluated the soft tissue frontal changes in relationship to movement of hard tissue with orthognathic surgery of facial asymmetry patients. Methods: Preoperative and postoperative frontal cephalograms and frontal view photographs of 45 mandibular surgery patients with facial asymmetry were obtained in a standardized manner. Vertical and horizontal changes of hard tissue and soft tissue were measured from cephalograms and photographs, respectively. Soft tissue change in result to hard tissue change was then analyzed. Results: Both vertical and horizontal correlation analysis showed a weak relationship between the changes. Hard tissue points that were picked for 1 : 1 mean ratio with soft tissue points did not show any significant relevance. For each soft tissue change, regressive equation was formulated by stepwise multiple regression analysis, and the equation for soft tissue Menton was most reliable in predicting changes. Both vertical and horizontal hard tissue changes were used together in prediction of vertical or horizontal soft tissue change. Conclusions: The results suggest that computerized image simulation using regression analysis may be of help for prediction of soft tissue change, while 1:1 mean ratio method is not useful.

• The korean journal of orthodontics
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• v.38 no.2
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• pp.83-94
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• 2008

Purpose: The first objective of this study was to compare the upper midface morpholgy, focusing on the soft tissues, between skeletal Class III maloccusion patients with midfacial depression and the norm. The second objective was to estimate and analyze the change in the upper midface soft tissues following surgical correction with maxillary advancement by Lefort I osteotomy and mandibular setback by bilateral sagittal split osteotomy (BSSRO). Methods: The samples consisted of 34 adult patients (15 males and 12 females) with an average age of 21 years, who had severe anteroposterior discrepancy with midfacial depression. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of simultaneous Lefort I osteotomy and BSSRO. Results: The correlation coefficient between changes in maxillary advancement and changes in Or' (soft tissue orbitale) was 0.599 (p < 0.05). Change in maxillary plane angle and vertical change of the maxilla were not correlated with the change in Or' (p < 0.05). The ratio of soft tissue change in Or' to maxillary advancement was 43.57 %, and 81.54 % in Sn. Regression equations between maxillary movement and Or' were devised. The $r^2$ value was 0.476. Conclusions: The majority of measurements in the upper midface in skeletal Class III maloccusions when compared to the norm, showed significant differences. In Class III malocclusion with midfacial depression, maxillary advancement produces soft tissue change in the upper midface.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.1
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• pp.63-71
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• 2011

Major type of facial asymmetry results from facial deformity and needs surgical correction. To diagnose facial asymmetry and set a treatment plane for patients, setting a sagittal reference plane is crucial. The purpose of this study is comparison of measurements of sagittal soft tissue reference point to three different sagittal planes. The subjects are 25 of asymmetry patients (M:15, F:10) and 19 of normal people. There are differences in point Gnathion and Stomion. Most of measurement of sagittal reference points showed within 1 mm difference from sagittal reference plane. Deviation of point Pronasale in Sa1 plane revealed significant difference among 3 reference planes. The deviation of Gnathion was proportional to the deviation of Stomion in all 3 reference planes.

• The korean journal of orthodontics
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• v.36 no.1 s.114
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• pp.1-13
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• 2006

Three-dimensional (3-D) laser scans can provide a 3-D image of the face and it is efficient in examining specific structures of the craniofacial soft tissues. Due to the increasing concerns with the soft tissues and expansion of the treatment range, a need for 3-D soft tissue analysis has become urgent. Therefore, the purpose of this study was to evaluate the scanning error of the Vivid 900 (Minolta, Tokyo, Japan) 3-D laser scanner and Rapidform program (Inus Technology Inc., Seoul, Korea) and to evaluate the mean error and the magnification percentage of the image obtained from 3-D laser scans. In addition, soft tissue landmarks that are easy to designate and reproduce in 3-D images of normal, Class II and Class III malocclusion patients were obtained. The conclusions are as follows; scanning errors of the Vivid 900 3-D laser scanner using a manikin were 0.16 mm in the X axis, 0.15 mm in the Y axis, and 0.15 mm in the Z axis. In the comparison of actual measurements from the manikin and the 3-D image obtained from the Rapidform program, the mean error was 0.37 mm and the magnification was 0.66%. Except for the right soft tissue gonion from the 3-D image, errors of all soft tissue landmarks were within 2.0 mm. Glabella, soft tissue nasion, endocanthion, exocanthion, pronasale, subnasale, nasal alare, upper lip point, cheilion, lower lip point, soft tissue B point, soft tissue pogonion, soft tissue menton and preaurale had especially small errors. Therefore, the Rapidform program can be considered a clinically efficient tool to produce and measure 3-D images. The soft tissue landmarks proposed above are mostly anatomically important points which are also easily reproducible. These landmarks can be beneficial in 3-D diagnosis and analysis.

• The korean journal of orthodontics
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• v.27 no.2
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• pp.181-196
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• 1997

The purpose of this study was to describe growth changes of soft tissue profile in koreans with normal occlusion and to get differences between male and female. The biennial serial cephalometric radiographs of 26 samples (15 males, 11 females) with normal occlusion from 8.5 years to 18.5 years of age were used in this study. The following results were obtained : 1. Both sexes had lower facial parts more protruded at 18.5 years of age than 8.5 years of age : in total facial convexity angle, male showed a decrease(P<0.01) and female showed no significant difference(P>0.05). 2. In the growth changes of soft tissue thickness, male outgrew female in the areas of nose and upper and lower lips, and female outgrew male in the pogonion area 3. In the growth changes of upper facial height and upper part of lower facial height, male's was higher than female's growth (P<0.05). 4. The ratio of the upper facial height over the lower facial height showed a decrease at 18.5 years of age than 8.5 years of age(P<0.01). The ratio of upper vs lower part of lower facial height and that of upper lip height vs lower lip height showed no significant difference(P>0.05). 5. Male showed a sustained change into older age compared with female in soft tissue profiles.

• The korean journal of orthodontics
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• v.29 no.4 s.75
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• pp.399-409
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• 1999

The purpose of this study was to evaluate the change of soft tissue profile on lower face following retraction of incisors through orthodontic treatment. 31 Korean women with bialveolar protrusion who were treated with 4 first bicuspid extraction were selected. All of samples were treated from above 17 years of age. Lateral cephalometric head films taken before and after treatment were analyzed statistically. The results were obtained as follows. $\cdot$The ratio of upper incisor retraction to upper lip retraction and lower incisor retraction to lower lip retraction were 1.54:1 (r=0.746) and 0.92:1 (r=0.584) respectively $\cdot$It appeared during orthodontic treatment that UIS-LS was increased considerably and the others in soft tissue thickness measurements were slightly decresed. $\cdot$Analysis of correlation showed that the change of the upper lip (LS) with the change of maxillary central incisor (UIS) and the change of lower lip with the change of B point were most strongly correlated. $\cdot$The multiple regression equations were obtained to predict soft tissue profile change of lower face according to retraction of incisors.

• The korean journal of orthodontics
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• v.35 no.6 s.113
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• pp.409-419
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• 2005

Studies for diagnostic analysis using three-dimensional (3D) CT images are recently in progress and needs for 3D craniofacial analysis are increasing in the fields of orthodontics. It is especially essential to analyze the facial soft tissue after orthodontic treatment and orthognathic surgery. In this study 3D CT images of adults with normal occlusion were taken to analyze the facial soft tissue. Norms were obtained from CT images of adults with normal occlusion (12 males, 11 females) using a computer program named V works 4.0 program. 3D coordinate planes were established using soft tissue Nasion as the reference point and a total of 20 reproducible landmarks of facial soft tissue were obtained using the multiple reconstructive sectional images (axial, sagittal and coronal images) of the V works 4.0 program: soft tissue Nasion, Pronasale, Subnasale, Upper lip center, Lower lip center, soft tissue B, soft tissue Pogonion, soft tissue Menton, Endocanthion (Rt/Lt), Alare lateralis (Rt/Lt), Cheilion (Rt/Lt), soft tissue Gonion (Rt/Lt), Tragus (Rt/Lt), and Zygomatic point (Rt/Lt). According to the established landmarks and measuring method, the 3D CT images of adults with normal occlusion were measured and the normal positional measurements and their Net (${\delta}=\sqrt{{X^2}+{Y^2}+{Z^2}}$) values were obtained using V surgery program, In the linear measurement between landmarks, there was a significant difference between males and females except Na' -Sn and En(Rt)-En(Lt). The normal ranges of Na'-Zy, Na'-Ch and Na'-Go' (facial depth) were obtained, which was difficult to measure by two-dimensional (2D) cephalometric analysis and facial photographs. These data may be used as references for 3D diagnosis and treatment planning for patients with malocclusion and dentofacial deformity.

• The korean journal of orthodontics
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• v.30 no.3 s.80
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• pp.343-355
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• 2000

The purpose of this study was to evaluate the amount and interrelationship of hard and soft tissue changes after mandibular setback osteotomy and reduction genioplasty in mandibular prognathism with long anterior facial height. The control group (Group A) consisted of 20 patients who had severe horizontal discrepancy. They experienced Presurgical orthodontic treatment and orthognathic surgery via mandibular setback. The experimental group (Group B) consisted of 20 patients who had severe horizontal and vertical discrepancy. They experienced presurgical orthodontic treatment and orthognathic surgery via mandibular setback and reduction genioplasty. The presurgical and postsurgical lateral cephalograms were evaluated. The computerized statistical analysis was tarried on with EXCEL 97 program. The results were as follows : 1. The correlation of hard and soft tissue horizontal changes in lower 2/3 of lower anterior facial height were high for both groups. The correlation coefficients of hard tissue changes and Ls, Stm, Li changes in Group B were moderately higher than Group A. 2. The correlation of hard and soft tissue vortical changes in Group B were lower than Group A. (except for pointB-Ils, Me-Me') 3. The ratio for soft tissue to Pog in Group B was lower than Group A. The ratios of hard and soft tissue vertical changes were 32% at Ils, 54% at Pog', and 60% at Me'. 4. The ratio of lower anterior facial height to total anterior facial height was reduced for both groups. But ratio of upper 1/3 of lower anterior facial height to total anterior facial height did not changed significantly in Group B. 5. Reduction genioplasty combined with mandibular setback procedure showed no change in upper one third(Sn-Stm) and significant decrease(Stm-Me') in the lower two thirds of the soft-tissue anterior lower facial height

• The korean journal of orthodontics
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• v.19 no.3
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• pp.87-97
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• 1989

This investigation was undertaken to know how soft tissue facial profile could be changed with age. The 3 serial lateral cephalometric roentgenograms of the twenty nine boys and twenty six girls between 9 and 13 years of age were studied and the findings seemed to warrant the following conclusions. 1. The author made the tables of means, standard deviations in each item, sex, age. 2. Soft tissue facial angle, soft tissue facial convexity including the nose tended to increase, but others tended to remain relatively stable. 3. Facial soft tissue thickness increased with age and the growth of facial soft tissue in the middle region (point A, LS, LI) was greater than others in the facial region. 4. In the soft tissue vertical proportions, G1'-Sn/Sn-Me' was 1.1, Sn-St/St-Me' was 0.51:1, Sn-LI/LI-Me' was 0.82:1 and those were stable with age.