• Toxicological Research
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• v.23 no.4
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• pp.331-339
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• 2007

Titanium or titanium alloy is a widely used implant material according to its certified biocompatibility, sufficient strength and ready availability. The purpose of this study was to evaluate the relative biocompatibility of titanium and titanium alloy specimens (Ti-29Nb-13Ta, TiNb and Ti-6Al-4V, Ti64) using in vivo and in vitro methods. For in vivo experiment, the specimens were implanted in the abdominal subcutaneous region of female mice for 2 and 4 weeks. The reaction of connective tissue to specimens was evaluated histologically. The specimens were encapsulated by fibrous connective tissue consisting of fibroblast, fibrocyte and other cells including neutrophil, macrophage, giant multinucleated cell and unidentified cells. Some newly formed blood vessels were located in the fibrous capsule surrounding the implant. Cell types and the thickness of fibrous capsules were examined quantitatively. Most of cell types located in the fibrous capsule were fibroblasts and fibrocytes. The average thickness of fibrous capsules for the TiNb specimens was much thinner than that of the titanium alloy, Ti64. The thickness of the fibrous capsule around all titanium specimens decreased at 4 weeks compared to 2 weeks post-implantation. The biocompatibility of titanium and titanium alloy specimens were also investigated in in vitro method using alkaline phosphatase from MG-63 cells. Alkaline phosphatase activity of the TiNb specimen showed higher activity than the titanium alloy, Ti64. In conclusion, the TiNb alloy with thin capsule thickness in vivo and high alkaline phosphatase activity in vitro will be of considerable use in biomedical applications.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.302-309
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• 2006

To evaluate the biocompatibility of untreated and anodized titanium specimens, the specimens were implanted in the subcutaneous tissue of the abdominal region of female mice for two weeks. The reaction of connective tissue to specimens was histologically studied. The implants were encapsulated by fibrous connective. tissue consisting of fibroblast, fibrocyte and other cellss including neutroophil, macrophage and giant multinucleated cell. some newly formed blood vessels were located in the fibrous capsule surrounding the implant. Giant multinucleated cells were observed at the fibrous capsule adjacent to the implant. Kind of cell types and the thickness of fibrous capsules were examined quantitatively. Most of cell types located in the fibrous capsule were fibroblast and fibrocyte. The average thickness of fibrous capsules for the anodized specimens was much thinner than that of the untreated titanium specimen. Biocompatibility of titanium specimens were also studied by using cell culture method. The number of MG-63 cells was significantly increased on the anodized titanium specimens in vitro experiment. Our observations suggest that anodized titanium specimens are more effective for the improvement of biocompatibility in vivo and in vitro.

• Toxicological Research
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• v.20 no.1
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• pp.13-20
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• 2004

The purpose of this study is to compare the biocompatibility of commercial purity Ti, Ti-6AI-4V and Ti-6AI-7Nb alloy specimens with and without surface treatment in mouse abdominal connective tissue in vivo. Each metal was implanted into specific abdominal subdermal tissue site of female mouse. After 4 weeks, the implants were removed and abdominal tissues were fixed, dehydrated and embedded in glycol methacrylate resin. And the tissues were histologically prepared for microscopical evaluation. It was characterized by the presence of connective tissue with fibrous capsule surrounding the implant. The fibrous tissue surrounding the implant was studied to determine the biocompatibility of implanted metals. The average thickness of the fibrous capsule formed around the implant was much thinner for the hydrogen peroxide added hydrochloric acid solution-treated specimen than for the others. The results of this evaluation indicate that modification of the surface properties of titanium and titanium alloy implants changes the biological properties in the abdominal connective tissue. In conclusion, these observations suggest that the proper surface treatment performed in the study is effective for the improvement of biocompatibility.

• Journal of Veterinary Clinics
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• v.32 no.5
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• pp.417-421
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• 2015

Bone grafting is widely used to bridge major bone defects or to promote bone union. Natural calcium carbonate (CC) has been used as a bone substitute material and used to scaffold for bone morphogenetic protein (BMP). The aims of this study is to evaluate the biocompatibility of cuttlebone (CB) and hydroxyapatite from CB (CBHA). Each material was shaped into disks (5 mm in diameter and 2 mm in thickness). To test biocompatibility, the disks were implanted into the dorsal subcutaneous tissue in mice. Fibrous capsule thickness around each disk was evaluated histologically at 2 and 4 weeks after implantation. Concerning biocompatibility, fibrous capsule thickness of CBHA was significantly thinner than that of CB and CHA (p < 0.05) at 2 and 4 weeks after implantation. Based on the clinical and histological results, CBHA would be a safe material for use inside the body and has more effective osteoconduction than CB.

• Journal of Periodontal and Implant Science
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• v.48 no.3
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• pp.152-163
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• 2018

Purpose: To determine whether the swelling and mechanical properties of osmotic self-inflating expanders allow or not the induction of intraoral soft tissue expansion in dogs. Methods: Three different volumes (0.15, 0.25, and 0.42 mL; referred to respectively as the S, M, and L groups) of soft tissue expanders (STEs) consisting of a hydrogel core coated with a silicone-perforated membrane were investigated in vitro to assess their swelling behavior (volume swelling ratio) and mechanical properties (tensile strength, tensile strain). For in vivo investigations, the STEs were subperiosteally inserted for 4 weeks in dogs (n=5). Soft tissue expansion was clinically monitored. Histological analyses included the examination of alveolar bone underneath the expanders and thickness measurements of the surrounding fibrous capsule. Results: The volume swelling ratio of all STEs did not exceed 5.2. In tensile mode, the highest mean strain was registered for the L group ($98.03{\pm}0.3g/cm$), whereas the lowest mean value was obtained in the S group ($81.3{\pm}0.1g/cm$), which was a statistically significant difference (P<0.05). In addition, the S and L groups were significantly different in terms of tensile strength ($1.5{\pm}0.1g/cm$ for the S group and $2.2{\pm}0.1g/cm$ for the L group, P<0.05). Clinical monitoring showed successful dilatation of the soft tissues without signs of inflammation up to 28 days. The STEs remained volumetrically stable, with a mean diameter in vivo of 6.98 mm, close to the in vitro post-expansion findings (6.69 mm). Significant histological effects included highly vascularized collagen-rich fibrous encapsulation of the STEs, with a mean thickness of $0.67{\pm}0.12mm$. The bone reaction consisted of resorption underneath the STEs, while apposition was observed at their edges. Conclusions: The swelling and mechanical properties of the STEs enabled clinically successful soft tissue expansion. A tissue reaction consisting of fibrous capsule formation and bone loss were the main histological events.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.4
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• pp.562-572
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• 2005

Statement of problem : Titanium is widely used as an implant material lot artificial teeth. Also, studies on surface treatment to form a fine passive film on the surface of commercial titanium or its alloys and improving bioactivity with bone have been carried out. However, there is insufficient data about the biocompatibility of the implant materials in the body. Purpose: The purpose of this study was to examine whether the precipitation of apatite on titanium metal is affected by surface modification. Materials and methods: Specimens chemically washed for 2 minute in a 1:1:1.5 (in vol%) mixture of 48% HF 60% $HNO_3$ and distilled water. Specimens were then chemically treated with a solution containing 97% $H_2SO_4$ and 30% $H_2O_2$ at $40^{\circ}C$S for 1 hour, and subsequently heat-treated at $400^{\circ}C$ for 1 hour. All specimens were immersed in the HBSS with pH 7.4 at $36.5^{\circ}C$ for 15 days, and the surface were examined with TF-XRD, SEM, EDX and XPS. Also, commercial purity Ti specimens with and without surface treatment were implanted in the abdominal connective tissue of mice for 4 weeks. Conventional aluminium and stainless steel 316L were also implanted for comparison. Results and conclusions : The results obtained were summarized as follows. 1. An amorphous titania gel layer was formed on the titanium surface after the titanium specimen was treated with a $H_2SO_4$ and $H_2O_2$ solution. The average roughness was $2.175{\mu}m$ after chemical surface treatment. 2. The amorphous titania was subsequently transformed into anatase by heat treatment at $400^{\circ}C$ for 1 hour. 3. The average thickness of the fibrous capsule surrounding the specimens implanted in the connective tissue was $46.98{\mu}m$ in chemically-treated Ti, and 52.20, 168.65 and $100.95{\mu}m$ respectively in commercial pure Ti, aluminum and stainless steel 316L without any treatment.

• Journal of Veterinary Clinics
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• v.32 no.5
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• pp.410-416
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• 2015

Bone grafting is widely used to bridge major bone defects or to promote bone union. In the evaluation of bone defect regeneration, 5 mm-diameter defects were created in rabbit calvaria. Concerning biocompatibility, fibrous capsule thickness of CBHA (hydroxyapatite from cuttlebone) was significantly thinner than that of CB (cuttlebone) and CHA (hydroxyapatite from coral) (p < 0.05) at 2 and 4 weeks after implantation. Concerning 12-week total changes of radiologic gray-level histogram, CBHA was significantly higher than CHA (p < 0.05). In the evaluation of bone defect regeneration, bone formation of CHA was significantly higher than that of CB and CBHA (p < 0.05). Based on the clinical and histological results, CBHA would be a safe material for use inside the body and has more effective osteoconduction than CB. It is suggested that CBHA is a valuable bone graft material.

• Korean Journal of Materials Research
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• v.15 no.5
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• pp.353-360
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• 2005

Surface treatment play an important role in nucleating calcium phosphate deposition on surgical Ti implant. Therefore, the purpose of this study is to examine whether the precipitation of apatite on cp-Ti and Ti alloys are affected by surface modification in HCl and $H_2O_2$ solution. Specimens were then chemically treated with a solution containing 0.1 M HCl and 8.8M $H_2O_2$ at $80^{\circ}C$ for 30 mins, and subsequently heat-treated at $400^{\circ}C$ for 1 hour. All specimens were immersed in the HBSS with pH 7.4 at $36.5^{\circ}C$ for 15 days, and the surface was examined with XRD, SEM, EDX ana XPS. Also, pure Ti, Ti-6Al-4V and Ti-6Al-7Nb alloy specimens with and without surface treatment were implanted in the abdominal connective tissue of mice for 4 weeks. All specimens chemically treated with HCl and $H_2O_2$ solution have the ability to form a apatite layer in the HBSS which has inorganic ion composition similar to human blood plasma. The average thickness of the fibrous capsule surrounding the specimens implanted in the connective tissue was $38.57\;{\mu}m,\;62.27\;{\mu}m\;and\;45.64\;{\mu}m$ in the cp-Ti, Ti-6Al-4V ana Ti-6Al-7Nb alloy specimens with the chemical treatment respectively, and $52.20\;{\mu}m,\;75.62\;{\mu}m\;and\;66.56\;{\mu}m$ in the commercial specimens of cp-Ti, Ti-6Al-4V and Ti-6Al-7Nb without any treatment respectively. The results of this evaluation indicate that the chemically treated cp-Ti, Ti-6Al-4V ana Ti-6Al-7Nb alloys have better bioactivity and biocompatibility compared to the other metals tested.

• Restorative Dentistry and Endodontics
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• v.9 no.1
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• pp.25-35
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• 1983

The purpose of this study was the observe the toxic effects of root canal sealers in 108 white rats. Experimental animals were divided into control and experimental groups. Theree representative types of materials, such as AH26, Z.O.E. and F.R. were used in this study. Cavities were prepared on the left mandibular area of 108 white rats. Three different sealers were placed in as experiment and bone cavities were left without filling as control. The experimental animals were sacrificed by cervical dislocation at the intervals of 1, 3, 7, 14, 28 and 49 days after filling. Each specimen was fixed with 10% neutral formalin solution, decalcified with 5% nitric acid, embedded in paraffin and sectioned 5-7${\mu}$. in thickness. The paraffin sections stained with Hematoxylin - Eosin were observed through the ordinary light microscope. The results were as follows; 1. Slight toxic effect to surrounding tissue were found in every experimental specimen. 2. AH26 showed the highest inflammatory response, and F.R. showed the lowest inflammatory response which subsided and replaced by fibrosis at 4 weeks after filling. 3. The cavity filled materials, such as implanted root canal sealers, blood clots and necrotic tissue, showed a tendency to be absorbed gradually proportioned to the experimental periods. A small amount of cavity filled materials were observed in the bone cavities after 4 weeks. 4. Fibroblastic proliferation began to produce fibrous capsule around the bone cavity in 2 weeks after filling. Fibrosis was prominent at 4 weeks after filling. 5. Osteoblastic activity of surrounding bone was observed at first in 2 weeks after filling and prominent in 4 weeks after filling. Osteoblastic activity showed an increasing effect as the time prolonged. 6. Surrounding tissue of the bone cavities showed the features of tissue destruction and had very severe inflammatory response at an initial stage. Above-mentioned appeared to be recovered gradually proportioned to the experimental periods.

• Journal of Chest Surgery
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• v.36 no.10
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• pp.711-720
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• 2003

Bakground : Complete resection by the surgery has been selected as the treatment of choice in lung cancer patients, but in cases of recurrence after excision or inoperable cases, the importance of anticancer chemotherapy has been emphasized. If one can select a set of the sensitive chemotherapeutic agents before anticancer chemotherapy, it will give more favourable results. Subrenal capsular assay has been recognized as a useful in-vivo chemosensitivity test of thoracic and abdominal tumors and it can be done in a short time for a rapid interpretation of tumor responsiveness to anticancer chemotherapeutic drugs. It has been reported that various kinds of cancer cells can be implantable to the kidney, but so far there is no comparative study of xenogeneic cell implantation on liver, spleen and kidney. The author implanted the human lung cancer cells under the capsule of S.D rat's liver, spleen and kidney respectively and compared the pattern of growth and histology. Material and Method: After incubation of human lung cancer cell line (SW-900 G IV) in RPMI 1640 (Leibovitz L-15 medium) culture media, 3${\times}$3${\times}$3 mm size fibrin clots which contain 108 cancer cells were made. Thereafter the fibrin clots were implanted at subcapsule area of liver, spleen and kidney of S.D. female rat. For immune suppression, cyclosporin-A (80 mg/Kg) was injected subcutaneously daily from post-implantation first day to sixth day. The body weight was measured at pre and post implantation periods. The growth pattern and the size of tumor mass were observed and the pathologic examination and serum tumor marker tests were performed. Result: Body weight increased in both of control and experimental groups. Serum Cyfra 21-1 was not detected. Serum levels of CEA and NSE revealed no significant change. The SCC-Ag increased significantly in implanted group. The growth rate of human lung cancer cells which was implanted on spleen was higher than on liver or kidney. The surface area, thickness, and volume of tumor mass were predominant at spleen. The success rates of implantation were 80% on kidney, 76.7% on spleen and 43.3% on liver. Pathologic examination of implanted tumors showed characteristic findings according to different organs. Tumors that were implanted on kidney grew in a round shape, small and regular pattern. In the spleen, tumors grew well and microscopic neovascularization and tumor thrombi were also found, but the growth pattern was irregular representing frequent daughter mass. Human lung cancer cells that were implanted in the liver, invaded to the liver parenchyme, and had low success rate of implantation. Microscopically, coagulation necrosis and myxoid fibrous lesion were observed. Conclusion: The success rate of implantation was highest in the kidney. And the mass revealed regular growth that could be measured easily. The SCC-Ag was presented earlier than CEA or Cyfra21-1. The Cyfra21-1 was not detected at early time after implantation. The best model for tumor implantation experiment for chemosensitivity test was subrenal capsular analysis than liver and spleen and the useful serum tumor marker in early period of implantation was the SCC-Ag.