• Journal of Korean Dental Science
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• v.15 no.1
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• pp.19-30
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• 2022

Purpose: The purpose of the study was to assess the validity of three-dimensional (3D) facial scan taken with facial scanner and digital photo wrapping on the cone-beam computed tomography (CBCT). Materials and Methods: Twenty-five patients had their CBCT scan, two-dimensional (2D) standardized frontal photographs and 3D facial scan obtained on the same day. The facial scans were taken with a facial scanner in an upright position. The 2D standardized frontal photographs were taken at a fixed distance from patients using a camera fixed to a cephalometric apparatus. The 2D integrated facial models were created using digital photo wrapping of frontal photographs on the corresponding CBCT images. The 3D integrated facial models were created using the integration process of 3D facial scans on the CBCT images. On the integrated facial models, sixteen soft tissue landmarks were identified, and the vertical, horizontal, oblique and angular distances between soft tissue landmarks were compared among the 2D facial models and 3D facial models, and CBCT images. Result: The results showed no significant differences of linear and angular measurements among CBCT images, 2D and 3D facial models except for Se-Sn vertical linear measurement which showed significant difference for the 3D facial models. The Bland-Altman plots showed that all measurements were within the limit of agreement. For 3D facial model, all Bland-Altman plots showed that systematic bias was less than 2.0 mm and 2.0° except for Se-Sn linear vertical measurement. For 2D facial model, the Bland-Altman plots of 6 out of 11 of the angular measurements showed systematic bias of more than 2.0°. Conclusion: The facial scan taken with facial scanner showed a clinically acceptable performance. The digital 2D photo wrapping has limitations in clinical use compared to 3D facial scans.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.3
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• pp.103-110
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• 2014

Objectives: In this study, we assessed soft tissue asymmetry that occurred after open reduction of unilateral zygomaticomaxillary complex (ZMC) fractures. We proposed a simple method to assess soft tissue asymmetry after reduction surgery by evaluating the symmetry between the affected and the unaffected sides. The factors affecting soft tissue contour after surgery were also analyzed. Materials and Methods: Subjects included patients admitted to Wonkwang University Dental Hospital from 2008 to 2013. Cone-beam computed tomography (CBCT) images of asymmetric patients who underwent open reduction at least 3 months prior were compared with healthy patients. Results: The degree of asymmetry was measured in both the open reduction and control groups. Landmarks that showed a statistically significant difference between the two groups were zygion ($1.73{\pm}0.24mm$), bucclae ($1.08{\pm}0.26mm$), point of cheek ($2.05{\pm}0.33mm$) and frontozygomatic point ($1.30{\pm}0.31mm$). Conclusion: When compared with the normal group, asymmetry can occur in the affected side, which usually shows depression of overlying soft tissue and is statistically significantly different. Evaluation of soft tissue asymmetry with CBCT images after open reduction of ZMC fracture is useful.

• The korean journal of orthodontics
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• v.51 no.3
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• pp.145-156
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• 2021

Objective: The aim of this retrospective study was to assess the midfacial soft tissue changes following maxillary expansion using micro-implant-supported maxillary skeletal expanders (MSEs) in young adults by cone-beam computerized tomography (CBCT) and to evaluate the correlations between hard and soft tissue changes after MSE usage. Methods: Twenty patients (mean age, 22.4 years; range, 17.6-27.1) with maxillary transverse deficiency treated with MSEs were selected. Mean expansion amount was 6.5 mm. CBCT images taken before and after expansion were superimposed to measure the changes in soft and hard tissue landmarks. Statistical analyses were performed using paired t-test and Pearson's correlation analysis on the basis of the normality of data. Results: Average lateral movement of the cheek points was 1.35 mm (right) and 1.08 mm (left), and that of the alar curvature points was 1.03 mm (right) and 1.02 mm (left). Average forward displacement of the cheek points was 0.59 mm (right) and 0.44 mm (left), and that of the alar curvature points was 0.61 mm (right) and 0.77 mm (left) (p < 0.05). Anterior nasal spine (ANS), posterior nasal spine (PNS), and alveolar bone width showed significant increments (p < 0.05). Changes in the cheek and alar curvature points on both sides significantly correlated with hard tissue changes (p < 0.05). Conclusions: Maxillary expansion using MSEs resulted in significant lateral and forward movements of the soft tissues of cheek and alar curvature points on both sides in young adults and correlated with the maxillary suture opening at the ANS and PNS.

• International Journal of Oral Biology
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• v.37 no.1
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• pp.25-29
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• 2012

During maxillofacial surgery, the infraorbital and mental nerves are blocked at eac foramen to induce local anesthesia. This study examined the relative locations of the infraorbital foramen (IOF) and mental foramen (MF) based on softtissue landmarks. Twenty-eight hemifacial cadavers were dissected to expose the IOF and MF. The distances between the bilateral IOFs, the bilateral MFs, the alae of the nose (alares), and the corners of the mouth (cheilions) were measured directly on cadavers by using a digital vernier caliper. The vertical and horizontal distances of the IOF and MF relative to the alare and cheilion were measured indirectly on digital photographs using Adobe Photoshop (Adobe, CA, USA). The distance between the bilateral IOFs ($58.09{\pm}4.04mm$) was longer than the distance between the bilateral MFs ($50.32{\pm}1.93mm$). The distances between the bilateral alares and cheilions were $41.22{\pm}3.44mm$ and $58.43{\pm}6.62mm$, respectively. The IOF was located $12.92{\pm}3.75mm$ superior and $7.88{\pm}2.56mm$ lateral to the alare, and the vertical angle (Angle 1) between these structures was $31.67{\pm}13.36^{\circ}$ superolaterally. The MF was located $21.83{\pm}3.26mm$ inferior and $5.56{\pm}3.37mm$ medial to the cheilion, and the vertical angle (Angle 2) between these structures was $14.05{\pm}10.12^{\circ}$ inferomedially. In conclusion, these results provide more detailed information about the locations of the IOF and MF relative to soft-tissue landmarks.

• Imaging Science in Dentistry
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• v.48 no.2
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• pp.111-119
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• 2018

Purpose: This study was conducted to evaluate the accuracy of linear measurements of 3-dimensional (3D) images generated by cone-beam computed tomography (CBCT) and facial scanning systems, and to assess the effect of scanning parameters, such as CBCT exposure settings, on image quality. Materials and Methods: CBCT and facial scanning images of an anthropomorphic phantom showing 13 soft-tissue anatomical landmarks were used in the study. The distances between the anatomical landmarks on the phantom were measured to obtain a reference for evaluating the accuracy of the 3D facial soft-tissue images. The distances between the 3D image landmarks were measured using a 3D distance measurement tool. The effect of scanning parameters on CBCT image quality was evaluated by visually comparing images acquired under different exposure conditions, but at a constant threshold. Results: Comparison of the repeated direct phantom and image-based measurements revealed good reproducibility. There were no significant differences between the direct phantom and image-based measurements of the CBCT surface volume-rendered images. Five of the 15 measurements of the 3D facial scans were found to be significantly different from their corresponding direct phantom measurements(P<.05). The quality of the CBCT surface volume-rendered images acquired at a constant threshold varied across different exposure conditions. Conclusion: These results proved that existing 3D imaging techniques were satisfactorily accurate for clinical applications, and that optimizing the variables that affected image quality, such as the exposure parameters, was critical for image acquisition.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.2 no.1
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• pp.23-27
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• 1972

A roentgenographic cephalometric study was made on the soft and hard tissue profile of Korean adults. The subject consisted of 52 males and 54 females from 17 to 22 years of age and with normal occlusion and acceptable profile. Twenty one landmarks were plotted and two oriented lines named SnH line and SnV line were drawn on the tracings of all cephalograms. The means and the standard deviations from the subjects were calculated in each measuring category and the means were compared with those of male and femal samples. The results were obtained as follow: 1. In depth and height, individual variations and sex differences of the lower facial profile were larger than the upper face. 2. The sex differences of upper facial profile were larger in height than depth. 3. The individual variations and sex differences of the top of nose were the smallest in all measuring points. 4. The thickness of the soft tissue of upper face and upper lip in male sample were larger than those of female, but the same matter were not found in mental region.

• The Korean Journal of Pain
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• v.24 no.4
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• pp.205-215
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• 2011

Background: Interventional pain management (IPM) is a branch of medical science that deals with management of painful medical conditions using specially equipped X-ray machines and anatomical landmarks. Interventional physiatry is a branch of physical medicine and rehabilitation that treats painful conditions through intervention in peripheral joints, the spine, and soft tissues. Methods: A cross-sectional study was conducted using three years of hospital records (2006 to 2008) from the Physical Medicine and Rehabilitation Department at Chittagong Medical College Hospital in Bangladesh, with a view toward highlighting current interventional pain practice in a tertiary medical college hospital. Result: The maximum amount of intervention was done in degenerative peripheral joint disorders (600, 46.0%), followed by inflammatory joint diseases (300, 23.0%), soft tissue rheumatism (300, 23.0%), and radicular or referred lower back conditions (100, 8.0%). Of the peripheral joints, the knee was the most common site of intervention. Motor stimulation-guided intralesional injection of methylprednisolone into the piriformis muscle was given in 10 cases of piriformis syndrome refractory to both oral medications and therapeutic exercises. Soft tissue rheumatism of unknown etiology was most common in the form of adhesive capsulitis (90, 64.3%), and is discussed separately. Epidural steroid injection was practiced for various causes of lumbar radiculopathy, with the exception of infective discitis. Conclusion: All procedures were performed using anatomical landmarks, as there were no facilities for the C-arm/diagnostic ultrasound required for accurate and safe intervention. A dedicated IPM setup should be a requirement in all PMR departments, to provide better pain management and to reduce the burden on other specialties.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.4-10
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• 2012

Purpose: The objective of this retrospective study was to assess the skeletal stability after orthognathic surgery for patients with cleft lip and palate. The soft tissue changes in relation to the skeletal movement were also evaluated. Methods: Thirty one patients with cleft received orthognathic surgery by one surgeon at the Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan. Osseous and soft tissue landmarks were localized on lateral cephalograms taken at preoperative (T0), postoperative (T1), and after completion of orthodontic treatment (T2) stages. Surgical movement (T0.T1) and relapse (T1.T2) were measured and compared. Results: Mean anteroposterior horizontal advancement of maxilla at point A was 5.5 mm, and the mean horizontal relapse was 0.5 mm (9.1%). The degree of horizontal relapse was found to be correlated to the extent of maxillary advancement. Mean vertical lengthening of maxilla at point A was 3.2 mm, and the mean vertical relapse was 0.6 mm (18.8%). All cases had maxillary clockwise rotation with a mean of 4.4 degrees. The ratio for horizontal advancement of nasal tip/anterior nasal spine was 0.54/1, and the ratio of A' point/A point was 0.68/1 and 0.69/1 for the upper vermilion/upper incisor tip. Conclusion: Satisfactory skeletal stability with an acceptable relapse rate was obtained from this study. High soft tissue to skeletal tissue ratios were obtained. Two-jaw surgery, clockwise rotation, rigid fixation, and alar cinch suture appeared to be the contributing factors for favorable results.

• The korean journal of orthodontics
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• v.29 no.5 s.76
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• pp.627-635
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• 1999

Soft tissue changes that occurred between presurgery to 5-years post-surgery in 49 orthognathic surgery patients whose maxillae were moved upward by Le Fort I osteotomy were examined by lateral cephalometric film. The objective of this paper was to document soft tissue changes at long-term follow-up after superior repositioning of the maxilla and to relate soft tissue and hard tissue changes in this group. The results were as follows. 1. On average, soft tissue landmarks in the nose and the upper lip were not changed statistically significantly except superior movement of superior labial sulcus and forward movement of pronasale between presurgery and 5 years postsurgery. 2. Upward and forward movement of the lower lip were found at 5 years postsurgery in comparison with presurgery and genioplasty added this effects. 3. Upper lip length and vertical dimension of upper vermilion didn't show any significant changes, but increase of lower lip length and decrease of vertical dimension of lower vermilion were statistically significant between presurgery and 5 years post-surgery. 4. The decrease of upper incisor exposure and interlabial distance from presurgery to 1 year were continued from 1 year to 5 years and the amount of the decrease was more than that of vertical movement of the maxilla by surgery. 5. Long term changes in soft tissue landmarks from 1 to 5 years postsurgery exceeded hard tissue changes, meaning soft tissue moved down more than skeletal changes.

• The korean journal of orthodontics
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• v.44 no.6
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• pp.281-293
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• 2014

Objective: Esthetic improvements during orthodontic treatment are achieved by changes in positions of the lips and surrounding soft tissues. Facial soft-tissue movement has already been two-dimensionally evaluated by cephalometry. In this study, we aimed to three-dimensionally assess positional changes of the adult upper lip according to simulated maxillary anterior tooth movements by white light scanning. Methods: We measured changes in three-dimensional coordinates of labial landmarks in relation to maxillary incisor movements of normal adults simulated with films of varying thickness by using a white light scanner. Results: With increasing protraction, the upper lip moved forward and significantly upward. Labial movement was limited by the surrounding soft tissues. The extent of movement above the vermilion border was slightly less than half that of the teeth, showing strong correlation. Most changes were concentrated in the depression above the upper vermilion border. Labial movement toward the nose was reduced significantly. Conclusions: After adequately controlling several variables and using white light scanning with high reproducibility and accuracy, the coefficient of determination showed moderate values (0.40-0.77) and significant changes could be determined. This method would be useful to predict soft-tissue positional changes according to tooth movements.