1.Comparison of Enhanced Dynamic Wedge with Physical Metal Wedge based on the Basic Dosimetric Parameters.
Jeong Woo LEE ; Semie HONG ; Kyoung Sik CHOI ; Jin Beom CHUNG ; Bo Young CHOE ; Hong Seok JANG ; Tae Suk SUH
Korean Journal of Medical Physics 2005;16(2):70-75
For clinical implementation of Enhanced Dynamic Wedge (EDW), it is necessary to adequately analyze and commission its dosimetric properties in comparison to common physical metal wedge (MTW). This study was implemented with the essential measurements of parameters for clinical application, such as percentage depth dose, peripheral dose, surface dose, effective wedge factor, and wedge profile. In addition, through the comparison study of EDW with open and MTW, the analysis was performed to characterize the EDW. We also compared EDW dose profiles of measured values using chamber array 24 (CA24) with calculated values using radiation treatment planning system. PDDs of EDW showed good agreements between 0.2~0.5% of open beam, but 2% differences with MTW. In the result of the measurements of peripheral dose, it was shown that MTW was about 1% higher than open field and EDW. The surface doses of 60degrees MTW showed 10% lower than the others. We found that effective wedge factor of EDW had linear relationships according to Y jaw sizes and was independent of X jaw sizes and was independent of X jaw sizes and asymmetric Y jaw opening. In comparison with measured values and calculate values from Golden-STT based radiation treatment planning system (RTP system), it showed very good agreement within difference of 1%. It could be concluded that EDW is a very reliable and useful tool as a beam modification substitute for conventional MTW.
Jaw
2.Accessory jaw bone: report of a case.
Sun Youl RYU ; Hee Kyun OH ; Geon Jung KIM ; Young Soo YUN
Journal of the Korean Association of Oral and Maxillofacial Surgeons 1992;18(4):130-136
No abstract available.
Jaw*
4.Clinico-histopathologic study on cysts of the jaw.
Journal of the Korean Association of Oral and Maxillofacial Surgeons 1993;19(1):22-36
No abstract available.
Jaw*
5.Clinico-histopathologic study on cysts of the jaw.
Journal of the Korean Association of Oral and Maxillofacial Surgeons 1993;19(1):22-36
No abstract available.
Jaw*
6.Study for hounsfield units in computed tomogram with jaw lesion.
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2006;32(4):391-396
The CT number is called Hounsfield unit(HU). Generally HU has a score between +1000 from -1000, and it is standardized usingthe air(-1000), water(0), and compact bone(+1000). Hounsfield Unit to standardize the density in computed tomography using the air and water has been used to analysis of lesion in other medical field. Computed tomography is popular method to analysis of lesion in oral and maxillofacial field but the analysis about density of lesion by Hounsfield unit is still obscure. For this study, computed tomography taken in Dankook University Dental Hospital and Hounsfield unit was measured to compare the difference of jaw bone lesion as cystic lesion, benign tumor, malignant tumor.
Jaw*
7.A morphological study on residual alveolar ridges of edentulous jaws .
Ho Young CHOI ; Yi Hyung WOO ; Dae Gyun CHOI
The Journal of Korean Academy of Prosthodontics 1991;29(1):73-89
No abstract available.
Jaw, Edentulous*
8.Finite element approach to investigate the influence of the design configuration of the ITI solid implant on the bone stresses during the osseointegration process.
Sang Bum CHA ; Kyu Bok LEE ; Kwang Hun JO
The Journal of Korean Academy of Prosthodontics 2006;44(2):217-228
STATEMENT OF PROBLEM: Standard type of ITI solid implant model in the 6.2mm thick jaw bone was axisymmetrically modelled for finite element stress analyses. PURPOSE: Primary objective was to investigate the influences of the characteristic design configuration of the ITI solid implant model on the bone stress with the course of osseointegration process at the bone/implant interfaces. To simulate the characteristics of the osseointegration process, five different stages of the bone/implant interface model were implemented. As load conditions, vertical load of 50N was taken into consideration. Bone at the cervical region of implant was the areas of concern where the higher level of stress were likely to take place. RESULTS: The results indicated that rather slightly different stress level could be obtained as a function of the osseointegration conditions. CONCLUSION: Under vertical load, the lower level of stress was observed at the cervical cortical bone in the initial and final stages of osseointegration. Relatively higher stress level, however, was observed during the transitional stages where the osseointegration at the cancellous bone interface were yet to fully develop.
Jaw
;
Osseointegration*
9.A clinical study of the osteoradionecrosis of the jaw.
Yong Kack KIM ; Heon Seok YU ; Jae Keun KWAK ; Kyu Yeong KIM
Journal of the Korean Association of Oral and Maxillofacial Surgeons 1993;19(2):177-184
No abstract available.
Jaw*
;
Osteoradionecrosis*
10.A clinical study of the osteoradionecrosis of the jaw.
Yong Kack KIM ; Heon Seok YU ; Jae Keun KWAK ; Kyu Yeong KIM
Journal of the Korean Association of Oral and Maxillofacial Surgeons 1993;19(2):177-184
No abstract available.
Jaw*
;
Osteoradionecrosis*