• Title/Summary/Keyword: bone exposure

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Effects of Different Timing of Implant Insertion on Osseointegration After Tooth Extraction;Histomorphometric and Biomechanical Studies (발치후 임프란트 매식 시기에 따른 골유착에 관한 연구;조직형태계측학적 및 생역학적 연구)

  • Oh, Hee-Kyun;Ryu, Sun-Youl
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.16 no.4
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    • pp.477-497
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    • 1994
  • The purpose of this study was to investigate the effect of timing of implant insertion on osseointegration after tooth extraction. Fifteen mongrel dogs, weighing 15kg or more, were used. The lower right 1st, 2nd, 3rd, 4th premolars and 1st molar were extracted under general anesthesia. Implants were inserted at 2, 4, and 8 weeks after extraction of the teeth, being designated as 2-, 4-, and 8-week groups, respectively. Results obtained were as follows. 1. Macroscopically there was neither an infection at the implant site nor an exposure of the implant. 2. Histologically the surrounding bone of the implant was less mature in the 2-week group than in the 4- and 8-week groups. 3. The implant-bone contact ranged from 75 to 82%, with no significant differences among the groups. No increase in the implant-bone contact was found with increasing healing periods from 4 to 12 weeks after implant insertions. 4. The average depth (0.64mm) of the fibrous connective tissue ingrowth in the 2-week group was slightly deeper than those in the 4- (0.51mm) and 8-week (0.53mm) groups at 12 weeks after implant insertion. 5. the implant-bone interfacial bond strengths were 73.05 kgf in the 2-week group, 69.71 kgf in the 4-week group and 73.76 kgf in the 8-week group. No significant difference was noted in pullout force among the groups. The degree of confidence of interfacial bone strength was highest in the 8-week group, followed by the 4- and 2-week groups. These results indicate that at least 4 weeks of healing period will be required before implant is to be inserted following tooth extraction.

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Clinical study of diagnosis and treatment of bisphosphonate-related osteonecrosis of the jaws (비스포스포네이트 관련 악골괴사의 진단 및 치료에 대한 임상적 연구)

  • Kim, Kyung-Wook;Kim, Beom-Jin;Lee, Chung-Hyun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.37 no.1
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    • pp.54-61
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    • 2011
  • Introduction: Bisphosphonates is used widely for the treatment of the Paget's disease, multiple myeloma, bone metastases of malignant tumors with the prevention of pain and their pathological fracture. However, it was recently suggested that bisphosphonates related osteonecrosis of the jaw (BRONJ) is a side effect of bisphosphonate use. Materials and Methods: Twenty-four individuals, who were referred to the Department of Oral and Maxillofacial surgery, Dankook University Dental Hospital, were selected from those who had exposed bone associated with bisphosphonates from January, 2005 to December, 2009 according to the criteria of American Association of Oral and Maxillofacial Surgeons (AAOMS) for BRONJ. The patients group consisted of 7 males and 17 females between the age of 46 to 78 years (average 61.8 years). Each patient had panoramic imaging, computed tomography (CT), whole body bone scanning performed for a diagnosis and biopsy sampling from the necrotizing tissue. C-terminal cross-linking telopeptide of type I collagen (CTX) level of patients who had undergone surgical intervention was measured 7 days before surgery. Results: The main cause of bone exposure was post-extraction (15), chronic periodontitis (4), persistent irritation of the denture (3). Twenty people had undergone BRONJ treatment for two to eight months except for 4 people who had to maintain the bisphosphonates treatment to prevent a metastasis and bone trabecular pain with medical treatment. When the bisphosphonate treatment was suspended at least for 3 months and followed up according to the AAOMS protocols, the exposed necrotizing bones were found to be covered by soft tissue. Conclusion: Prevention therapy, interruption of bisphophonates for at least 3 months and cooperation with the physician for conservative treatment are the essential for treating BRONJ patient with high risk factors. The CTX level of BRONJ patients should be checked before undergoing surgical intervention. Surgical treatments should be delayed in the case of a CTX level <150 pg/mL.

BISPHOSPHONATE(ZOLEDRONIC ACID) RELATED OSTEOMYELITIS ON MANDIBLE-A CASE REPORT (Bisphosphonate(Zoledronic acid)와 연관된 하악골의 골수염-증례보고)

  • Lee, Su-Youn;Choi, So-Young;Kim, Jin-Wook;Kwon, Tae-Geon;Jang, Hyung-Jung;Kim, Chin-Soo;Lee, Sang-Han
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.30 no.4
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    • pp.395-398
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    • 2008
  • Bisphosphonate are a class of drugs with a chemical structure which inhibit bone resorption, actually used for metastatic bone disease, osteoporosis, Paget's disease and multiple myeloma. Significant complication associated with their use is reported recently : mandibular and maxillary osteomyelitis or osteonecrosis. So we here report our case about the patient who was diagnosed of prostate cancer in 2004 April and treated with bisphosphonate(Zoledronic acid-$Zometa^{(R)}$, Novartis Co.) intravenously every 3 to 4weeks at a dose of 4mg to prevent bone metastasis, and also, the patient who came to the hospital due to the bony exposure of mandible and pain in 2006 November and was diagnosed osteomyelitis of mandible as a result of biopsy, bone scan, PET CT examination.

Midfacial degloving approach for management of the maxillary fibrous dysplasia: a case report

  • Kang, Miju;Jee, Yu-jin;Lee, Deok won;Jung, Sang-pil;Kim, Se-won;Yang, Sunin;Ryu, Dong-mok
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.40
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    • pp.38.1-38.9
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    • 2018
  • Background: Fibrous dysplasia (FD) is a benign bone lesion characterized by the progressive replacement of normal bone with fibro-osseous connective tissue. The maxilla is the most commonly affected area of facial bone, resulting in facial asymmetry and functional disorders. Surgery is an effective management option and involves removing the diseased bone via an intraoral approach: conservative bone shaving or radical excision and reconstruction. Case presentation: This case report describes a monostotic fibrous dysplasia in which the patient's right midface had a prominent appearance. The asymmetric maxillary area was surgically recontoured via the midfacial degloving approach under general anesthesia. Follow-up photography and radiographic imaging after surgery showed the structures were in a stable state without recurrence of the FD lesion. Furthermore, there were no visible scars or functional disability, and the patient reported no postoperative discomfort. Conclusions: In conclusion, the midfacial degloving approach for treatment of maxillary fibrous dysplasia is a reliable and successful treatment option. Without visible scars and virtually free of postoperative functional disability, this approach offers good exposure of the middle third of the face for treatment of maxillary fibrous dysplasia with excellent cosmetic outcomes.

Health and Safety at Work: Analysis from the Brazilian Documentary Film Flesh and Bone

  • Mendes, Luciano;dos Santos, Heliani Berlato;Ichikawa, Elisa Yoshie
    • Safety and Health at Work
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    • v.8 no.4
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    • pp.347-355
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    • 2017
  • Background: The objective of this article is to make some analysis on the process of work and accidents occurring in slaughterhouses, evidenced in the Brazilian documentary film called Flesh and Bone. As such, it was necessary to discuss an alternative theoretical concept in relation to theories about health and safety at work. This alternative discussion focuses on the concepts of biopower and biopolitics. Methods: The use of audiovisual elements in research is not new, and there is already a branch of studies with methodological and epistemological variations. The Brazilian documentary Flesh and Bone was the basis for the research. The analysis of this documentary will be carried out from two complementary perspectives: "textual analysis" and "discourse analysis." Results: Flesh and Bone presents problems related to health and safety at work in slaughterhouses because of the constant exposure of workers to knives, saws, and other sharp instruments in the workplace. The results show that in favor of higher production levels, increased overseas market sales, and stricter quality controls, some manufacturers resort to various practices that often result in serious injuries, disposal, and health damages to workers. Conclusion: Flesh and Bone, by itself, makes this explicit in the form of denunciation based on the situation of these workers. What it does not make clear is that, in the context of biopolitics, the actions aimed at solving these problems or even reducing the negative impacts for this group of workers, are not efficient enough to change such practices.

A Study of Micronucleus Induction with Methyl Formate and 2-Methylbutane in Bone Marrow Cells of Male ICR Mice

  • Kim, Soo-Jin;Rim, Kyung-Taek;Kang, Min-Gu;Kim, Jong-Kyu;Chung, Yong-Hyun;Yang, Jeong-Sun
    • Safety and Health at Work
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    • v.1 no.1
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    • pp.80-86
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    • 2010
  • Objectives: We investigated the genotoxicity of two chemicals, methyl formate and 2-methylbutane, using male ICR mice bone marrow cells for the screening of micronucleus induction. Although these two chemicals have already been tested numerous times, a micronucleus test has not been conducted and the amounts used have recently been increased. Methods: 7 week male ICR mice were tested at dosages of 250, 500, and 1,000 mg/kg for methyl formate and 500, 1,000, and 2,000 mg/kg for 2-methlybutane, respectively. After 24 hours of oral administration with the two chemicals, the mice were sacrificed and their bone marrow cells were prepared for smearing slides. Results: As a result of counting the micronucleated polychromatic erythrocyte (MNPCE) of 2,000 polychromatic erythrocytes, all treated groups expressed no statistically significant increase of MNPCE compared to the negative control group. There were no clinical signs related with the oral exposure of these two chemicals. Conclusion: It was concluded that the two chemicals did not induce micronucleus in the bone marrow cells of ICR mice, and there was no direct proportion with dosage. These results indicate that the two chemicals have no mutagenic potential under each study condition.

Effects of Soy Protein on Bone Mineral Content and Bone Mineral Density in Growing Male Rats (콩단백질이 성장기 수컷흰쥐에서 골함량과 골밀도에 미치는 영향)

  • 최미자
    • Journal of Nutrition and Health
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    • v.35 no.4
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    • pp.409-413
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    • 2002
  • The purpose of this study was to determine to which differences in the source of protein (soy vs casein) and of isoflavones in soy protein are responsible for differential effects of bone mineral density and bone mineral content. Thirty 21-d-old Sprague-Dawley young rats were divided into 3 groups: the control group was find a casein-based diet, the soy concentrate group was fed soy protein with totally reduced isoflavones content (isoflavone 0.07 mg/g protein), and soy isolate group was fed with a higher isoflavone content (isoflavone 3.4 mg/g protein) than normal. The animal was scanned to determine the BMD and BMC using dual energy X-ray absorptiometry (DEXA, Lunar Corporation, Madison, WI). The soy concentrate group had significantly higher total body calcium/weight and total mineral content/weight than the casein group. The soy isolate group had significantly greater total bone mineral density/weight, spine bone mineral density/weight, and femoral bone mineral density (in g/$\textrm{cm}^2$ than the control and soy concentrate group. The findings of this study suggest that soy protein and isoflavones in soy protein are beneficial for bone-formation in growing male rats. Therefore exposure to these soy protein and isoflavones early in life may have long-term health benefits for bone diseases such as osteoporosis.

Radiological Accident and Acute Radiation Syndrome (방사선 사고와 급성 방사선 증후군)

  • Roh, Hyung-Keun
    • Journal of The Korean Society of Clinical Toxicology
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    • v.9 no.2
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    • pp.39-48
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    • 2011
  • In mass casualty situation due to radiological accidents, it is important to start aggressive management with rapid triage decisions. External contamination needs immediate decontamination and internal contamination should be treated with special expertise and equipment to prevent the rapid uptake of radionuclides by target organs. Acute radiation syndrome shows a sequence of events that varies with the severity of the exposure. More severe exposures generally lead to more rapid onset of symptoms and severe clinical findings. After the massive exposure, various systems of the body reflect their severe damages that can lead to death within hours or up to several months. The disease progression has classically been divided into four stages: prodromal, latent, manifest illness, and recovery or death. Three characteristic clusters of symptoms including the hematopoietic syndrome, the gastrointestinal syndrome and the cerebrovascular syndrome are all associated with the acute radiation syndrome. The standard medical management of the patients with a potentially survivable radiation exposure includes good medical, surgical and supportive measures. Specific treatment with cytokines and bone marrow transplantation should be considered. The management of internal contamination is much the same as the treatment of poisoning. The standard decontamination should be applied to reduce uptake, and the chelating agents can be administered to enhance the clearance of radioisotopes. Radioactive iodine ($^{131}I$) as one of the nuclear fission products can increase the incidence of thyroid cancer in children. Potential benefit of potassium iodide prophylaxis is greater especially in neonates, infants and small children.

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Establishment of a Murine Model for Radiation-induced Bone Loss in Growing C3H/HeN Mice (성장기 마우스에서 방사선 유도 골소실 동물모델 확립)

  • Jang, Jong-Sik;Moon, Changjong;Kim, Jong-Choon;Bae, Chun-Sik;Kang, Seong-Soo;Jung, Uhee;Jo, Sung-Kee;Kim, Sung-Ho
    • Journal of Radiation Protection and Research
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    • v.40 no.1
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    • pp.10-16
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    • 2015
  • Bone changes are common sequela of irradiation in growing animal. The purpose of this study was to establish an experimental model of radiation-induced bone loss in growing mice using micro-computed tomography (${\mu}CT$). The extent of changes following 2 Gy gamma irradiation ($2Gy{\cdot}min^{-1}$) was studied at 4, 8 or 12 weeks after exposure. Mice that received 0.5, 1.0, 2.0 or 4.0 Gy of gamma-rays were examined 8 weeks after irradiation. Tibiae were analyzed using ${\mu}CT$. Serum alkaline phosphatase (ALP) and biomechanical properties were measured and the osteoclast surface was examined. A significant loss of trabecular bone in tibiae was evident 8 weeks after exposure. Measurements performed after irradiation showed a dose-related decrease in trabecular bone volume fraction (BV/TV) and bone mineral density (BMD), respectively. The best-fitting dose-response curves were linear-quadratic. Taking the controls into accounts, the lines of best fit were as follows: BV/TV (%) = $0.9584D^2-6.0168D+20.377$ ($r^2$ = 0.946, D = dose in Gy) and BMD ($mg{\cdot}cm^{-3}$) = $8.8115D^2-56.197D+194.41$ ($r^2$ = 0.999, D = dose in Gy). Body weight did not differ among the groups. No dose-dependent differences were apparent among the groups with regard to mechanical and anatomical properties of tibia, serum ALP and osteoclast activity. The findings provide the basis required for better understanding of the results that will be obtained in any further studies of radiation-induced bone responses.

Combined Effects of Iron and Zinc on Accumulation of Lead in Some Organs of Rats (아연(亞鉛)과 철분(鐵分) 동시투여(同時投與)가 백서(白鼠)의 장기내(臟器內) 연함량(鉛含量)에 미치는 영향(影響))

  • Ohm, Hyung-Taek;Song, Dong-Bin;Cha, Chul-Whan
    • Journal of Preventive Medicine and Public Health
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    • v.16 no.1
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    • pp.19-24
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    • 1983
  • In order to study the effects of iron and zinc on the lead poisoning of rats, lead with iron and zinc, or lead alone were administered orally to a total of 98 adult rats of Sprague-Dawley Species. The concentrations of lead, zinc, and iron were measured by atomic absorption spectrophotometer at every 20 days intervals of 20th, 40th, 60th, 80th and 120th day as a final measurement. Those datas were analysed and compared with those of control groups. The results were summarized as follows; 1. The concentration of lead in blood, bone. and liver tissues kept increasing in case of lead exposure group whereas it started decreasing at 60-80th day when concentration of zinc started increasing in case of combined exposure group. However, in kidney tissue, the concentration of lead in combined exposure group kept increasing up to the end of observation showing special high concentration at the final measurement at 120th day. 2. Concentration of zinc in blood and liver tissues had increased from 60-80th day in case of combined exposure group. 3. Concentration of iron in blood showed decreasing from $44.15{\pm}9.67\;to\;32.44{\pm}2.69{\mu}g/ml$ in case of lead exposure group, whereas it showed constant level of $47.50{\sim}45.65{\mu}g/ml$. However, in liver tissue it kept constant as control did from 40th to 60th days, but from 100th day on it started increasing to show much higher concentration than control.

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