• 치과방사선
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• 제27권1호
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• pp.99-106
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• 1997

The purpose of this study was to compare & to find out the variability of head film measurements (and marks identification) between Fuji computed radiographic cephalometry and conventional cephalometry. 28 Korean adults were selected. Lateral cephalometric FCR film and conventional cephalometric film of each subject was taken. Four investigators identified 24 cephalometric landmarks on lateral cephalometric FCR film and conventional cephalometric film. The comparable measurements between lateral cephalometric FCR film and conventional cephalometric film were statistically analysed. The results were as follows : 1. In FCR film & conventional film, coefficient of variation (C.V.) of 24 landmarks was taken horizonta1ly & vertically. There is no significant difference of rank order of landmarks in C.V. between two films. 2. In comparison of significant differences of landmarks variability between FCR film & conventional film, horizontal value of coefficient of variation, showed significant differences in four landmarks among twenty-four landmarks, but vertical value of coefficient of variation showed significant differences in sixteen landmarks among twenty-four landmarks. FCR film showed significantly less variability than conventional film in 17 subjects among 20(4+16) subjects that showed significant difference.

• Imaging Science in Dentistry
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• 제35권1호
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• pp.15-23
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• 2005

Purpose : To compare cephalometric measurement between measuring methods in digital and conventional lateral cephalometric radiograph. Materials and Methods : Twenty digital and conventional lateral cephalometric radiographs were selected. In digital group, cephalometric measurements were performed manually using hardcopies and automatically using $V-Ceph^{TM}$ program on the monitor. In conventional group, the same measurements were performed manually on conventional films, and for automatic measurement conventional films were digitized by scanner. All measurements were performed twice by 4 observers, and 24 cephalometric variables were calculated and the time spent for each measurement was recorded. The differences in measurements data and the time spent for each measurement were compared within each group. Intra-observer and inter-observer comparisons were performed. Results : In both groups, no statistically significant difference between manual and automatic measurements was observed and most of the variables didn't show statistically significant differences between methods. The observer with less experience tended to show statistically significant differences of measurements between methods, and differences from other observers. The differences of measurements between methods in digital group were lesser than those of conventional group with statistical significance in 8 variables out of 24. With automatic method and in digital group, the spent time was shorter. Conclusion : With direct digital radiograph, automatic method using manually idenitified landmarks can be preferable in cephalometric analysis. (Korean J Oral Maxillofac Radiol 2005; 35 : 15-23)

• 대한치과교정학회지
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• 제24권3호
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• pp.521-534
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• 1994

The purpose of this study was to compare the differences in measurements between cephalometric radiographs and digigraphs of Dolphin Imaging System. 26 Korean adult male and 24 adult female with normal occlusion were selected. For each subject lateral cephalogram was taken. Digitizing with Digigraph Work Station of Dolphin in System. was performed as well. 50 tracings and 50 digigraphs were analyzed with Yonsei, Ricketts, Burstone analyses. The comparable measurements between tracing group and digigraph group were statistically analyzed. The results were as follows: 1. 13 of 64 comparable measurements did not show any statistically significant difference (P>0.05) between tracing group and digigraph group. 2. Three of the measurements with FH plane as a reference plane did not show any statistically insignificant difference. All measurement with SN plane as a reference plane showed statistically significant difference(p<0.05). 3. The measurements which showhed no statistically significant difference were mostly short distance linear measurements while most of the angular measurements showed statistically significant difference(p<0.05).

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권4호
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• pp.353-359
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• 1999

Purpose : A new method of lateral cephalometric analysis for midface, focusing on zygomatic bone, was created in this study, and measured in Korean adults. The purposes of this study are understanding about new approach for midfacial depression, especially zygomatic bone, and using to make adequate diagnosis and treatment plan. Materials and methods : In this study, esthetic Korean adults, 25 males and 25 females who were between $0^{\circ}$ and $4^{\circ}$ in ${\angle}ANB$, and between 62% and 70% in P/A facial height ratio, and had normal overbite and overjet, were used. Orbitale(Or) and Soft tissue orbitale(Or') were used for indicators of anteroposterior position of zygomatic area. And, mean value and standard deviation of linear and angular measurements, and ratio about each linear measurements, were obtained. then, standard deviation diagram - wiggle diagram - was made for visualization of results. Results : Mean values, standard deviations and ranges of 19 measurements were obtained, and among them, 5 linear measurements that had large standard deviation were excluded and the others were used for making standard deviation diagram. In standard deviation diagram, the following results were obtained. 1. If the measurements are located on more left side of mean-value-vertical -line, the potential of midfacial hypoplasia are stronger, especially zygomatic area. 2. If the measurements are located on more right side of mean-value-vertical-line, the potential of midfacial hypoplasia are decreased. Conclusion : This study presented a new method of lateral cephalometric analysis focusing on zygomatic bone in Korean adults. We expect that the results of this study can be used as parameter when clinicians make decisions about diagnosis and treatment plan for rehabilitation of esthetics and function. But, it is necessary to prove its usefulness, and to further evaluate the results.

• 대한치과교정학회지
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• 제44권5호
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• pp.254-262
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• 2014

Objective: The purpose of this study was to evaluate the relation between idiopathic scoliosis and facial deformity in the horizontal, vertical, and anteroposterior planes. Methods: A total of 123 female patients aged 14 years or older, who visited the Spine Clinic at the Department of Orthopedics, Korea University Guro Hospital for treatment of idiopathic scoliosis, were enrolled. Whole-spine anteroposterior and lateral radiographs were taken with the patient in a naturally erect position, and frontal and lateral cephalograms were taken in an erect position with the Frankfort horizontal line parallel to the floor. Scoliosis was classified according to the Cobb angle and Lenke classification of six curve types. Cephalometric tracing in all cases was carried out with V-Ceph 5.5 by the same orthodontist. The Kruskal-Wallis test was performed to determine whether any relation existed between each group of the idiopathic scoliosis classification and the cephalometric measurements of frontal and lateral cephalograms. Results: The measurements did not reveal any significant association between the Cobb angle and cephalometric measurements and between the curve type based on the Lenke classification and cephalometric measurements. Conclusions: Based on the results of this study, no apparent relation was observed between the severity of scoliosis and facial form variations in idiopathic scoliosis patients.

• Imaging Science in Dentistry
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• 제39권3호
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• pp.133-147
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• 2009

Purpose : To investigate the reproducibilities and compare the measurements in digital and MDCT-synthesized cephalometric radiograph, and to investigate the effect of head position on the measurement during imaging with MDCT. Materials and Methods : Twenty-two dry skulls (combined with mandible) were used in this study. Conventional digital cephalometric radiograph was taken in standard position, and MDCT was taken in standard position and two rotated position ($10^{\circ}$ left rotation and $10^{\circ}$ right tilting). MDCT data were imported in $OnDemand^{(R)}$ and lateral cephalometric radiograph were synthesized from 3D virtual models. Two types of rotated MDCT data were synthesized with default mode and with corrected mode using both ear rods. For all six images, sixteen angular and eleven linear measurements were made in V-$Ceph^{(R)}$ three times. Reproducibility of measurements was assessed using repeated measures ANOV A and ICC. Linear and angular measurements were compared between digital and five MDCT-synthesized images by Student t-test. Results : All measurements in six types of cephalometric radiograph were not statistically different under ICC examination. Measurements were not different between digital and MDCT-synthesized images (P>.05). Measurements in MDCT-synthesized image in $10^{\circ}$ left rotation or $10^{\circ}$ right tilting position showed possibility of difference from digital image in some measurements, and possibility of improvement via realignment of head position using both ear rods. Conclusion : MDCT-synthesized cephalometric radiograph can substitute conventional cephalometric radiograph. The error on head position during imaging with MDCT have possibility that can produce measurement errors with MDCT-synthesized image, and these position error can be corrected by realignment of the head position using both ear rods.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권4호
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• pp.168-174
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• 2013

Objectives: The aim of this study is to investigate the correlation between 2-dimensional (2D) cephalometric measurement and 3-dimensional (3D) cone beam computed tomography (CBCT) measurement, and to evaluate the availability of 3D analysis for asymmetry patients. Materials and Methods: A total of Twenty-seven patients were evaluated for facial asymmetry by photograph and cephalometric radiograph, and CBCT. The 14 measurements values were evaluated and those for 2D and 3D were compared. The patients were classified into two groups. Patients in group 1 were evaluated for symmetry in the middle 1/3 of the face and asymmetry in the lower 1/3 of the face, and those in group 2 for asymmetry of both the middle and lower 1/3 of the face. Results: In group 1, significant differences were observed in nine values out of 14 values. Values included three from anteroposterior cephalometric radiograph measurement values (cant and both body height) and six from lateral cephalometric radiographs (both ramus length, both lateral ramal inclination, and both gonial angles). In group 2, comparison between 2D and 3D showed significant difference in 10 factors. Values included four from anteroposterior cephalometric radiograph measurement values (both maxillary height, both body height) and six from lateral cephalometric radiographs (both ramus length, both lateral ramal inclination, and both gonial angles). Conclusion: Information from 2D analysis was inaccurate in several measurements. Therefore, in asymmetry patients, 3D analysis is useful in diagnosis of asymmetry.

• 치과방사선
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• 제27권2호
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• pp.105-116
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• 1997

The purpose of this study is to evaluate the cephalometric reproducibility in digitized cephalometric radiography by comparing the measurement errors between the remeasured and retaken conventional and digitized lateral cephalometric radiography. The mean of the differences and error percentage of each cephalometric measurement were obtained using 96 lateral cephalometric radiography from 48 patients between the age of 11 and 13. The results were as follows; 1. The repeated measurement group of conventional radiography showed least amount of mean differences while those of the retaken measurement group of digitized image showed largest amount of mean differences in every measurement. 2. The measurements which showed statistically significant difference between the conventional radiography and digitized image were S-Go, Ar-Go, S-Ar-Go and S-sN-sNT in repeated measurement group. 3. The measurements which showed statistically significant difference between the repeated and retaken measurement groups were N-S-Ar, MP-Ll and S-sN-sPog in conventional radiography and S-N, Go-Me and N-A in digitized Image. 4. Large amount of error percentage was shown at A-N-B and N-A in retaken measurement group of conventional radiography and N-S-Ba and A-N-B in retaken measurement group of digitized image. 5. The amount of error percentage at Ar-Go and N-S- Ar in retaken measurement group of conventional radiography and S-N, N-A, S-N-B and N-S-Ba in retaken measurement group of digitized image was more than double than those from remeasured groups.

• 대한치과교정학회지
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• 제47권1호
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• pp.31-38
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• 2017

Objective: This study aimed to quantitatively assess the relationship of smile esthetic variables with various types of malocclusion, and identify the cephalometric factors affecting smile measurements. Methods: This retrospective study included 106 patients who were treated with retention at the orthodontic department of Taipei Medical University Hospital. Hard-tissue variables were measured using lateral cephalographic tracings, and nine smile esthetic variables were measured using facial photographs. The patients were divided into three groups according to their overjet (< 0, 0-4, and > 4 mm). An analysis of variance was conducted to compare the pretreatment cephalometric variables and smile esthetic variables among the three groups. Multiple linear regression analysis was performed to identify the cephalometric factors affecting the smile measurements in each group. Results: Except the upper midline and buccal corridor ratio, all of the smile measurements differed significantly among the three groups before orthodontic treatment. Some of the smile characteristics were correlated with the cephalometric measurements in different types of malocclusion. The overjet was the major factor influencing the smile pattern in all three types of malocclusion. Conclusions: Smile characteristics differ between different types of malocclusion; the smile may be influenced by skeletal pattern, dental procumbency, or facial type. These findings indicate that establishment of an optimal horizontal anterior teeth relationship is the key to improving the smile characteristics in different types of malocclusion.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제19권4호
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• pp.333-342
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• 1997

The purpose of this study was to establish a set of standard values for the form of the nose and its relationship to other craniofacial structures in young korean adults in angle's class I occlusion. The subjects were 40 (20 male, 20 female) Korean dental students in angle's class I occlusion. Lateral cephalometric radiographs were used to determine the form of the nose and its positon relative to other craniofacial structures. The results were obtained as followed. 1. There was a significance between the registered male and female measurements in nasal height(P<0.05). (Male: 58.23mm Female : 54.62mm) 2. There was a significance between the registered male and female measurements in nasal length(P<0.05). (Male : 54.18mm Female : 49.38mm) 3. The vertical distances from the tip of the nose in Korean adults were significantly greater in the male(P<0.05) and were smaller in both sex in comparison with caucasian.