• Imaging Science in Dentistry
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• v.43 no.3
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• pp.135-143
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• 2013

Purpose: This study was performed to obtain a quantitative evaluation of the cortical and cancellous bone graft harvestable from the mental and canine regions, and to evaluate the cortical vestibular thickness. Materials and Methods: This study collected cone-beam computed tomographic (CBCT) images of 100 Italian patients. The limits of the mental region were established: 5 mm in front of the medial margin of each mental foramen, 5 mm under the apex of each tooth present, and above the inferior mandibular cortex. Cortical and cancellous bone volumes were evaluated using SimPlant software (SimPlant 3-D Pro, Materialize, Leuven, Belgium) tools. In addition, the cortical vestibular thickness (minimal and maximal values) was evaluated in 3 cross-sections corresponding to the right canine tooth (3R), the median section (M), and the left canine tooth (3L). Results: The cortical volume was $0.71{\pm}0.23mL$ (0.27-1.96 mL) and the cancellous volume was $2.16{\pm}0.76mL$ (0.86-6.28 mL). The minimal cortical vestibular thickness was $1.54{\pm}0.41mm$ (0.61-3.25 mm), and the maximal cortical vestibular thickness was $3.14{\pm}0.75mm$ (1.01-5.83 mm). Conclusion: The use of the imaging software allowed a patient-specific assessment of mental and canine region bone availability. The proposed evaluation method might help the surgeon in the selection of the donor site by the comparison between bone availability in the donor site and the reconstructive exigency of the recipient site.

• Imaging Science in Dentistry
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• v.47 no.1
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• pp.25-31
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• 2017

Purpose: The aim of this study was to compare the diagnostic accuracy of previously trained endodontists in the detection of artificially created periapical lesions using cone-beam computed tomography (CBCT) and digital periapical radiography (DPR). Materials and Methods: An ex vivo model using dry skulls was used, in which simulated apical lesions were created and then progressively enlarged using #1/2, #2, #4, and #6 round burs. A total of 11 teeth were included in the study, and 110 images were obtained with CBCT and with an intraoral digital periapical radiographic sensor (Instrumentarium dental, Tuusula, Finland) initially and after each bur was used. Specificity and sensitivity were calculated. All images were evaluated by 10 previously trained, certified endodontists. Agreement was calculated using the kappa coefficient. The accuracy of each method in detecting apical lesions was calculated using the chisquare test. Results: The kappa coefficient between examiners showed low agreement (range, 0.17-0.64). No statistical difference was found between CBCT and DPR in teeth without apical lesions (P=.15). The accuracy for CBCT was significantly higher than for DPR in all corresponding simulated lesions(P<.001). The correct diagnostic rate for CBCT ranged between 56.9% and 73.6%. The greatest difference between CBCT and DPR was seen in the maxillary teeth (CBCT, 71.4%; DPR, 28.6%; P<.01) and multi-rooted teeth (CBCT, 83.3%; DPR, 33.3%; P<.01). Conclusion: CBCT allowed higher accuracy than DPR in detecting simulated lesions for all simulated lesions tested. Endodontists need to be properly trained in interpreting CBCT scans to achieve higher diagnostic accuracy.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.2
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• pp.76-82
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• 2014

Objectives: The aim of this study is to report the results of extracorporeal fixation in patients with mandibular condylar fractures and compare them with the clinical results of conservative treatment. Materials and Methods: The medical records of 92 patients (73 male [M] : 19 female [F], age 13-69 years, mean 33.1 years) treated for condylar fractures at the Department of Oral and Maxillofacial Surgery in Sun Dental Hospital (Daejeon, Korea) from 2007 to 2012 were reviewed. Patients were divided into three groups: group A (23 patients; M : F=18 : 5, age 21-69 years, mean 32.6 years), treated with extracorporeal fixation; group B (30 patients; M : F=24 : 6, age 16-57 years, mean 21.1 years), treated by conventional open reduction; and group C (39 patients; M : F=31 : 8, age 16-63 years, mean 34.4 years), treated with the conservative method ('closed' reduction). Clinical and radiographic findings were evaluated and analyzed statistically. Results: Occurrence of postoperative condylar resorption correlated with certain locations and types of fracture. In this study, patients in group A (treated with extracorporeal fixation) did not demonstrate significant postoperative complications such as malocclusion, mandibular hypomobility, temporomandibular disorder, or complete resorption of condyle fragments. Conclusion: In superiorly located mandibular condyle fractures, exact reconstruction of condylar structure with the conventional open reduction technique can be difficult due to the limited surgical and visual fields. In such cases, extracorporeal fixation of the condyle using vertical ramus osteotomy may be a better choice of treatment because it results in anatomically accurate reconstruction and low risk of complications.

• Progress in Medical Physics
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• v.11 no.2
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• pp.147-155
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• 2000

Patient dose verification is one of the most important parts in quality assurance of the treatment delivery for radiation therapy. The dose distributions may be meaningfully improved by modulating two dimensional intensity profile of the individual high energy radiation beams In this study, a new method is presented for the pre-treatment dosimetric verification of these two dimensional distributions of beam intensity by means of a charge coupled device video camera-based fluoroscopic device (henceforth called as CCD-VCFD) as a radiation detecter with a custom-made software for dose calculation from fluorescence signals. This system of dosimeter (CCD-VCFD) could reproduce three dimensional (3D) relative dose distribution from the digitized fluoroscopic signals for small (1.0$\times$1.0 cm$^2$ square, ø 1.0 cm circular ) and large (30$\times$30cm$^2$) field sizes used in intensity modulated radiation therapy (IMRT). For the small beam sizes of photon and electron, the calculations are performed In absolute beam fluence profiles which are usually used for calculation of the patient dose distribution. The good linearity with respect to the absorbed dose, independence of dose rate, and three dimensional profiles of small beams using the CCD-VCFD were demonstrated by relative measurements in high energy Photon (15 MV) and electron (9 MeV) beams. These measurements of beam profiles with CCD-VCFD show good agreement with those with other dosimeters such as utramicro-cylindrical (UC) ionization chamber and radiographic film. The study of the radiation dosimetric technique using CCD-VCFD may provide a fast and accurate pre-treatment verification tool for the small beam used in stereotactic radiosurgery (SRS) and can be used for verification of dose distribution from dynamic multi-leaf collimation system (DMLC).

• Clinics in Shoulder and Elbow
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• v.2 no.1
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• pp.1-7
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• 1999

Purpose : There has been considerable controversy as to the method of the treatment of acute acromioclavicular joint dislocation classified to type III injury. The purpose of this study is to compare the conservative and operative treatment of the type III acute acromioclavicular joint dislocation in terms of clinical and radiological results. Materials and Methods: We treated 31 cases of acute, type III acromioclavicular joint dislocation, 17 cases were treated by operative methods and 14 patients by conservative treatment, and 1 year minimum follow-up was done from January 1990 to January 1996. We used UCLA Shoulder Rating Scale for clinical results. And for the radiological results coracoclaviclar distance were measured. We used Fisher's exact test for statistical analysis of results between the two treatment methods. Results: Fifteen(88.2%) of seventeen patients in operative treatment and eleven(78.6%) of fourteen patients in nonoperative treatment were rated excellent or good on the UCLA rating scale. In radiographic evaluation, the average coracoclavicular distances of preoperative state, immediate postoperation(or postreduction) and last follow-up were as follows. In operative cases, it was 1.75±0.21mm, 1.14±0.24mm and 1.33± 0.22mm respectively. In nonoperative cases, it was 1.65±0.14mm, 1.26±0.26mm, and 1.42±0.27mm respectively. Conclusion : This study demonstrated that there was no significant difference in clinical and radiological results between the operative and nonoperative treatment groups. So, nonoperative treatment is recommended for acute type III acromioclavicular dislocation as general rule.

• Journal of Korean Neurosurgical Society
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• v.49 no.6
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• pp.351-354
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• 2011

Objective : This investigation was conducted to evaluate a new, safe entry point for the C2 pedicle screw, determined using the anatomical landmarks of the C2 lateral mass, the lamina, and the isthmus of the pars interarticularis. Methods : Fifteen patients underwent bilateral C1 lateral mass-C2 pedicle screw fixation, combined with posterior wiring. The C2 pedicle screw was inserted at the entry point determined using the following method : 4 mm lateral to and 4 mm inferior to the transitional point (from the superior end line of the lamina to the isthmus of the pars interarticularis). After a small hole was made with a high-speed drill, the taper was inserted with a 30 degree convergence in the cephalad direction. Other surgical procedures were performed according to Harm's description. Preoperatively, careful evaluation was performed with a cervical X-ray for C1-C2 alignment, magnetic resonance imaging for spinal cord and ligamentous structures, and a contrast-enhanced 3-dimensional computed tomogram (3-D CT) for bony anatomy and the course of the vertebral artery. A 3-D CT was checked postoperatively to evaluate screw placement Results : Bone fusion was achieved in all 15 patients (100%) without screw violation into the spinal canal, vertebral artery injury, or hardware failure. Occipital neuralgia developed in one patient, but this subsided after a C2 ganglion block. Conclusion : C2 transpedicular screw fixation can be easily and safely performed using the entry point of the present study. However, careful preoperative radiographic evaluation, regardless of methods, is mandatory.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.2
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• pp.148-156
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• 2007

Purpose: The aim of this study is the changes of upper respiratory airway space in patients with mandibular prognathism after 2-jaw orthognathic surgery in patients with skeletal classs III malocclusion. Method: We measured the lines between selected upper airway landmarks on lateral cephalometric x-ray films of skeletal class III 64 persons who had not been operated yet, were 6 months after operation. The test subjects were divided into 3 groups according to maxillary movement, as follows; maxillary advancement (MA) group, maxillary posterior impaction (MPI) group, maxillary posterior impaction and superior repositioning (MPI+MSR) group. Result: In this study, nasopharyngeal airway space in MPI+MSR group was significantly increased after operation (p<0.05). Oropharygeal and hypopharyngeal airway space in MA group and MPI group were significantly decreased after operation (p<0.05). From hyoid bone to anterior mandible point distance in MA group and MPI group were significantly decreased after operation (p<0.05). Conclusion: Oropharygeal and hypopharyngeal airway space were influenced more by mandibular set-back than maxillary movement. Maxillary movement surgery as well as mandibular setback surgery should be taken into consideration in order to minimize symptoms related to obstructive sleep apnea syndrome after operation.

• Journal of Korean Foot and Ankle Society
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• v.8 no.2
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• pp.142-148
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• 2004

Purpose: We compared the results of three surgical procedures of the old neglected Freiberg's disease that was managed with metatarsal head reshaping, metatarsal head resection, and dorsal closing wedge osteotomy. Materials and Methods: From march 1996 to July 2002, five cases in six patients whose metatarsal head collapse already progressed underwent operative treatment. We compared the operative results in the view point of the radiographic follow-up and lesser toe metatrasophalangeal joint scale of AOFAS. Results: There were no further joint destruction and loose body formation. Also, lesser toe metatrasophalangeal joint scale of AOFAS improved from average score, 38.5 (range $22{\sim}49$) of preoperative one to average score, 86.6 (range, $72{\sim}100$). Especially, the 2 cases that underwent dorsal closing wedge osteotomy showed most favorable result and the 2 cases with metatarsal resection showed next favorable result. The 2 cases with intra-articular loose body removal and metatarsal reshaping showed the least effective result among three operative methods. Conclusion: Our Operative experiences of old neglected Freiberg's disease were all satisfactory irrespective of operative options and dorsal closing wedge osteotomy was thought to be most effective method.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.355-361
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• 2014

The aim of the present study was to evaluate a relative emission of image plate (IP) in computed radiography (CR) system by using relative sensitivity in film/screen methods. The characteristic curve was obtained by using the uniform aluminum 11-step wedge penetrometer. X-ray exposure factors on radiographic digital image were 50 kVp, 10 mAs. We adjusted zero of all parameter of algorithms (MUSICA) so proximate to raw data and applied to 200 of exposure class. Modeling on relative emission of IP are used IP without fading time and IP after 4 hours, 8 hours, 12 hours, 24 hours in the respective storage after X-ray exposure. The results of this study showed that the sensitivity point density at the measuring of relative sensitivity in CR was suited pixel values of the 2000 easy to relatively measure the characteristic curve and when relative sensitivity is decreased, the amount of light emitted from the image signal for generating was also decreased. In conclusion, the proposed method of measurement of relative sensitivity can be utilized to evaluate the quantity of relative emission of IP in CR system.

• The Journal of Korean Physical Therapy
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• v.25 no.5
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• pp.246-251
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• 2013

Purpose: The purpose of this study was to provide quantitative data regarding development of the chest wall in children with cerebral palsy (CP) according to Gross Motor Function Classification System (GMFCS) levels and age using the radiological image diameter measurement method. Methods: Subjects included 112 children with CP and 110 healthy children, All of the children underwent simple chest x-ray. The diameters of the upper chest ($D_{apex}$) and lower chest ($D_{base}$) were measured on the anteroposterior (AP) view of a chest x-ray, and the $D_{apex}$ to $D_{base}$ ratio was calculated. Chest wall ratios were compared among children with CP at GMFCS levels I ~ III, GMFCS levels IV and V, and healthy children. Results: The results showed significant differences between the upper and lower chest wall diameters of children with CP at GMFCS levels IV and V, and healthy children (F=4.54, p=0.01; F=3.20, p=0.04). Results of comparison between the chest wall ratios of children with CP and healthy children, showed that the upper chest walls of healthy children were significantly larger in children younger than 48 months (p<0.05), and both the upper and lower chest walls of healthy children were significantly larger compared to children with CP in children older than 48 months (p<0.05). Conclusion: Radiographic measurement for examination of chest wall development is relatively simple, and the results yield quantitative data on development of the chest wall for children with CP. In addition, therapeutic interventions may be considered based on the results.