Castleman disease is a rare disease entity of unknown etiology, with the characteristics of large, wellmarginated benign lymphoid masses occuring predominently in the mediastinum. the value of contrast enhancement insolid soft tissue masses of mediastinum has little been written because most of the solid mediastinal tumors showno significant degree of enhancement. But Castleman disease, because of its hypervascularity, shows significantdegree of enhancement in most cases. Authors report 3 cases of Castlemen disease and suggests good diagnosticprobability of Castlman disease in cases that show benign looking homogeneously enhancing mediastinal mass by CTscan.
Giant Lymph Node Hyperplasia ; Lymph Nodes ; Mediastinum ; Rare Diseases

No abstract available.
Hyperostosis, Cortical, Congenital*

STATEMENT OF PROBLEM: Regardless of any restoration, most of case, we used in screw connection between abutment and implant. For this reason, implant screw loosening has been remained problem in restorative practices. PURPOSE: The purpose of this study was to compare surface of coated/plated screw with titanium and gold alloy screw and to evaluate physical property of coated/plated material after scratch test in FESEM investigation. MATERIAL AND METHODS: GoldTite, titanium screw provided by 3i (Implant Innovation, USA) and TorqTite, titanium screw by Steri-Oss (Nobel Biocare, USA) and gold screw, titanium screw by AVANA (Osstem Implant, korea) - were selected for this study. Each abutment screw surface was observed at 100 times, and then screw crest, root, and slope were done more detailed numerical value, at 1000 times with FESEM. A micro-diamond needle was also prepared for the scratch test. Each abutment screw was fixed, micro-diamond scratch the surface of head region was made at constant load and then was observed central region and periphery of fine trace through 1000 times with FESEM. RESULTS: The surface of GoldTite was smoother than that of other kinds of screw and had abundant ductility and malleability compared with titanium and gold screw. The scratch test also showed that teflon particles were exfoliated easily in screw coated with teflon. Titanium screw had a rough surface and low ductility. CONCLUSION: It was recommended that the clinical use of gold-plated screw would prevent a screw from loosening.
Alloys ; Head ; Needles ; Polytetrafluoroethylene ; Titanium

STATEMENT OF PROBLEM: Implant screw loosening has been remained problem in restorative practices. Surface treatment of screw plays a role of preventing screw from loosening in implant screw mechanism. PURPOSE: The purpose of this study was to investigate surface characteristics of TiN and ZrN film ion plated screw with titanium and gold alloy screw and to evaluate wear resistance, surface roughness, and film adhesion on screw surface using various instruments. MATERIAL AND METHODS: GoldTite screws and titanium screws provided by 3i (Implant Innovation, USA) and TorqTite screws or titanium screws by Steri-Oss (Nobel Biocare, USA) and gold screws and titanium screws by AVANA (Osstem Implant, korea) were selected. Ion plating which is much superior to other surface modification techniques was carried out for gold screws and titanium screws using Ti and Zr coating materials with nitrogen gas. Ion nitrided surface of each abutment screw was observed with field emission scanning electron microscopy(FE-SEM), micro-diamond scratch tester, vickers hardness tester, and surface roughness tester. RESULTS: 1) The surface of gold screw and GoldTite is more smooth than ones of other kinds of non coated screw. 2) The ZrN and TiN coated surface is the more smooth than ones of other kinds of screw. 3) The hardness of TiN and ZrN coated surface showed higher than that of non coated surface. 4) The TiN coated titanium screw and ZrN coated gold screw have a good wear resistance and adhesion on the surface. 5) The surface of ZrN coated screw showed low surface roughness compared with the surface of TiN coated screw. CONCLUSION: It is considered that the TiN and ZrN coated screw which would prevent a screw from loosening can be appilcable to implant system and confirmed that TiN and ZrN film act as lubricant on surface of screw due to decrease of friction for recycled tightening and loosening.
Alloys ; Dental Implants* ; Friction ; Hardness ; Hardness Tests ; Nitrogen ; Tin ; Titanium

Chordoma arising from the notochordal remnants is a rare primary bone tumor in the cervicosacral region and is even more unusual in the thoracic region. The authors experienced a case of thoracic chordoma and report its CT and MR findings.
Chordoma* ; Notochord

Chordoma arising from the notochordal remnants is a rare primary bone tumor in the cervicosacral region and is even more unusual in the thoracic region. The authors experienced a case of thoracic chordoma and report its CT and MR findings.
Chordoma* ; Notochord

No abstract available.
Olfactory Mucosa*

The present study has been undertaken to pursue the cytotoxic effects of cis-Platin on the osteoid formation in metaphysis of rat tibia. By using the immunohistological staining method for type I collagen in rat tibial osteoid, the author detected the deposition of type I collagen, which is the collagenous constituent of endochondral osteoid, after administration of cis-Platin in experimental animals. For the immunological reactions of type I collagen, we used the rabbit anti-rat collagen type I polyclonal antibody as primary antibody and biotinylated goat anti-rabbit IgG as secondary antibody. The distributions of immunohistological reactions in the each of metaphyseal osteoids were analyzed with an image analyzer, and we studied the variances of type I collagens by statistical probabilities. In 12 hours after cis-Platin injection, immunoreactive area in the osteoid of metaphysis was distinctly decreased. Immunoreactive area of type I collagen in osteoids of 1 day and 3 days group metaphysis was increased more than that of 12 hours group and the type I collagen in the metaphysis showed weak immunoreactions of type I collagens with an image analyzer. In the osteoids of 7 days group after cis-Platin injection, the immunoreactive area was similar to that of control group. It is consequently suggested that cis-Platin would induce the decrease of type I collagen in the osteoid. But the type I collagen in tibial osteoid shows the increase from a few days after cis-Platin injection.
Animals ; Collagen ; Collagen Type I* ; Goats ; Immunoglobulin G ; Rats* ; Tibia*

STATEMETN OF PROBLEM: Surface alteration of the implant screws after function may be asso-ciated with mechanical failure. Theses metal fatigue appears to be the most common cause of structural failure. PURPOSE: The purpose of this study was to evaluate surface alteration of the implant screws after function through the examination of used and unused implant screws in SEM(scanningelectron microscope). MATERIAL AND METHODS: In this study, abutment screws(Steri-oss, 3i), gold retaining screw(3i) and titanium retaining screw(3i) were retrieved from patients. New, unused abutment and retain-ing screws were prepared for control group. Each of the old, used screws was retrieved with a screwdriver. And retrieved implant complex of Steri-oss system was prepared for this study. Then, SEM investigation and EDS analysis of abutment and retaining screws were per-formed. And SEM investigation of cross-sectioned sample of retrieved implant complex was performed. RESULTS: In the case of new, unused implant screws, as maunfactured circumferential grooves are regularly examined and screw thread are sharply remained. Before ultrasonic cleans-ing of old, used implant screw, a lot of accumulation and corrosion products were existed. After ultrasonic cleansing of old, used implant screws, circumferential grooves as examined before function were randomly deepened and scratches increased. Also, dull screw thread was examined. More surface alterations after function were examined in titanium screw than gold screw. And more surface alteration was examined when retrieved with driver than retrieved without driver. CONCLUSIONS: These surface alteration after function may result in the screw instability. Regularly cleansing and exchange of screws was recommended. We recommend the use of gold screw rather than titanium screw, and careful manipulation of the driver.
Corrosion ; Fatigue ; Humans ; Titanium ; Ultrasonics

PURPOSE: The aim of this study is to evaluate the effect of TiN coating of abutment screw on the unscrewing torque. MATERIAL AND METHODS: Titanium and Gold-Tite abutment screws were classified into two groups, Group A and C respectively, as control groups. Titanium abutment screws with TiN coatings were also classified into two groups, Group B and D, as experimental ones. Group A and B were tightened to 20 Ncm input torque, and Group C and D were tightened to 32 Ncm torque. Detorque values were measured with digital torque gauge during repeated closing and opening experiment. RESULTS: Abutment screws with TiN coating (Group B and D) showed statistically significant higher mean detorque values than those of Group A and C. DISSCUSION: Physical properties of TiN coating, such as low friction coefficient, high hardness and wear resistance, might contribute to higher detorque values. CONCLUSION: It is suggested that TiN coating of abutment screw help to reduce the risk of screw loosening and improve the stability of screw joint.
Friction ; Hardness ; Joints ; Tin* ; Titanium ; Torque