• Title/Summary/Keyword: Apposition

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A study on the biological characteristics of modified titanium surface (매식체 표면처리에 따른 생물학적 특성에 대한 연구)

  • Kim, Jae-Hyuk;Chung, Chin-Hyung;Lim, Sung-Bin;Hong, Ki-Seok
    • Journal of Periodontal and Implant Science
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    • v.38 no.3
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    • pp.453-466
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    • 2008
  • Purpose: The purpose of this research is to study about initial adhesion, proliferation and activation of osteoblast to titanium surface treated with machined, hydroxyapatite coating, resorbable blast material blasting and anodizing method. Material and Methods: After treating the titanium surface of each block with machined, impurities were removed and sterilized. The number of cells attached from cultured osteoblast of respective experimental groups were measured at 1, 4, 7, and 14day and alkaline phosphatase, calcium, and inorganic phosphate concentration of cultured solution was measured. Result: Anodizing group showed the highest rate of cell attachment and proliferation activity. RBM treated group showed the highest increasing on their alkaline phosphatase activity, on the calcium apposition, on inorganic phosphate apposition of 1 and 4 days in cultured osteoblast to compare with other groups. Conclusion: On the basis of these findings, we conclude that surface modification of titanium was profoundly effected on the attachment, proliferation and activation of osteoblast in initial stage osseointegration.

Intermittent Administration of Parathyroid Hormone for Orthodontic Tooth Movement in Mongrel Dogs: Preliminary Study

  • Won-Ho Kim;Bo Ram Lee;Hey-Yun Kim;Minji Kim;Jin-Woo Kim
    • Journal of Korean Dental Science
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    • v.16 no.2
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    • pp.182-191
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    • 2023
  • Purpose: This study investigated the orthodontic tooth movement after weekly parathyroid hormone (PTH) injection in mongrel dogs and analyzes bone formation activity on the tension and pressure sides of the tooth movement in mongrel dogs. Materials and Methods: Three mongrel dogs were used in this study. The first premolar was extracted and orthodontic force using 150 g of closed coil springs between the canine and second premolar was applied. The low-dose PTH group (PTH_1) and high-dose PTH group (PTH_2) received weekly injections of 1.61 ㎍/kg and 3.23 ㎍/kg of PTH, respectively. The control group received weekly injections of 1 ml of saline. Clinical, histomorphometric analysis were carried out. Result: The orthodontic tooth movement was greatest in the PTH_2 group and the lowest in the control group. Fluorescence staining images showed higher bone remodeling on the tension side of the tooth movement in the PTH_1 and PTH_2 groups. PTH_2 group showed a thicker labeling band than the PTH_1 group. PTH_2 group showed the highest mineral apposition rate and bone formation rate, followed by the PTH_1 group and the control group. Conclusion: Weekly intermittent PTH injection, especially in the short-term and at higher doses with orthodontic force, successfully increased orthodontic tooth movement and bone remodeling in mongrel dogs.

Activation of Porcine Oocytes Following Intracytoplasmic Injection of Various Sperm Components and foreign species spermatozoa (여러 가지 정자구성성분 및 이종정자 주입에 의한 돼지난자의 활성)

  • Jun, S.H.;Shin, J.S.;Do, J.T.;Kwon, J.K.;Kim, N.H.;Lee, H.T.;Chung, K.S.
    • Clinical and Experimental Reproductive Medicine
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    • v.25 no.3
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    • pp.331-340
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    • 1998
  • We determined the incidence of activation, male pronuclear formation and apposition of pronuclei in porcine oocytes following intracy-toplasmic injection of various porcine sperm components and foreign species spermatozoa, such as mouse, human or cattle. The porcine oocytes were activated by injection of a spermatozoon or an isolated sperm head. Neither isolated sperm tail nor perinuclear material removed sperm head activated oocytes. Because injection of mouse, bovine or human spermatozoon activated porcine oocytes, the sperm born activation factors is not strict species specific. Male pronuclear formation and pronuclear apposition were observed in the porcine oocytes following injection of porcine, bovine, mouse or human spermatozoa. The electrical stimulation following sperm cell injection did not enhance the incidence of male pronuclear formation nor pronuclear apposition comparent with sperm cell injection alone (p>0.1). Mitosis and two cell division in some oocytes were observed at 20 to 24 h after injection of porcine spermatozoon. However, none of oocytes following injection of mouse, bovine or human spermatozoa developed to the mitotic metaphase or normally divided to the two cell stage. These results suggested that the oocyte activating factor(s) presented in the perinuclear material and it is not species specific for the porcine oocyte.

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Bone Healing around Screw - shaped Titanium Implants with Three Different Surface Topographies (임플란트의 표면처리 유형에 따른 골 치유 양상)

  • Koh, Young-Han;Kim, Young-Jun;Chung, Hyun-Ju
    • Journal of Periodontal and Implant Science
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    • v.31 no.1
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    • pp.41-57
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    • 2001
  • It is well known that the apposition of bone at implant surface would be influenced by the microstructure of titanium implants. The purpose of this study was to compare bone healing around the screw-shaped titanium implant with three different surface topographies in the canine mandibles by histological and biomechanical evaluation. All mandibular premolars of six mongrel dogs were extracted and implants were placed one month later. The pure titanium implants had different surface topographies: smooth and machined ($Steri-OSS^{(R)}$: Group II); sandblasted and acid-etched ($ITI^{(R)}$, SLA: Group III) surface. The fluorescent dyes were injected on the 2nd (calcein), 4th (oxytetracycline HCI) and 12th (alizarin red) weeks of healing. Dogs were sacrificed at 4 and 12 weeks after implantation. The decalcified and undecalcified specimens were prepared for histological and histo-metrical evaluation of implant-bone contact. Some specimens at 12 weeks after implantation were used for removal torque testing. Histologically, direct bone apposition to implant surface was found in all of the treated groups. More mature and dense bone was observed at the implant-bone interface at 12 weeks than that at 4 weeks after implantation. Under the fluorescent microscope, thick regular green fluorescent lines which mean early bone apposition were observed at the implant-bone interface in Group III, while yellow and red fluorescent areas were found at the implant-bone interface in Group I and II. The average implant-bone contact ratios at 4 weeks of healing were 54.3% in Group I, 57.7% in Group II and 66.2% in Group III. In Group I, implant-bone contact ratio was significantly lower than Group II and III(p<0.05). The average implant-to-bone contact ratios at 12 weeks after implantation were 64.3% in Group I, 66.7% in Group II and 71.2% in Group III. There was no significant difference among the three groups. In Group I and II, the implant-bone contact ratio at 12 weeks increased significantly in comparison to ratio at 4 weeks(p<0.05). The removal torque values at 12 weeks after implantation were 90.9 Ncm in Group I, 81.6 Ncm in Group II and 77.1 Ncm in Group III, which were significantly different(p<0.05). These results suggest that bone healing begin earlier and be better around the surface-treated implants compared to the smooth surface implants. The sandblasted and acid-etched implants showed the most favorable bone response among the three groups during the early healing stage and could reduce the waiting period prior to implant loading.

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AN EXPERIMENTAL STUDY ON THE EFFECT OF THE MANDIBULAR RETRACTIVE FORCE ON THE MANDIBULAR CONDYLE OF GROWING YOUNG DOG (하악 후방 견인력이 성장기 유견의 하악과두에 미치는 영향에 관한 실험적 연구)

  • Lim, Yong-Kyu;Yang, Won-Sik
    • The korean journal of orthodontics
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    • v.20 no.2
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    • pp.363-379
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    • 1990
  • The purpose of this study was to evaluate the effects of the mandibular retractive force on the mandibular condyle of growing dog. The experimental animals were six mongrel dogs of two-month old. Their deciduous dentition were completed. Two of them was used as control group, and experimental group was composed of remaining four. Head band and chin cup were made of cotton tape, and hooks are fabricated on the chin cup and had band for closed coil. Mandibular retractive force was 100g/side and chin cap appliance was used for 14 hours/day during night. Experimental group were sacrificed at 2, 4, 6, 8 weeks from beginning of the experiment. Right TMJ was prepared for histologic study and left TMJ was examined grossly for disc, fossa, and condyle. The conclusions are: 1. Two-month old control animal showed active cartilaginous growth on the mandibular condyle, therefore showed thick proliferative and hypertrophic zones. Remodeling process in the condyle head was observed in which there were bone resorption on the anterior surface and bone apposition on the posterior surface. 2. Four-month old control animal showed marked reduction of hypertrophic zone but the condylar bone remodeling was more pronounced. 3. In experimental group, there are marked reduction of hypertrophic zone at 4 weeks from beginning of experiment, and hypertrophic zone disappeared at posterior-superior portion of condyle in 6-week experimental animal. 8 week experimental animal showed slight recovery of hypertrophic zone. 4. In experimental group, bone deposition was increased at anterior surface of condyle, and bone resorption was increased at posterior surface of condyle. 5. In control group, the glenoid fossa and surrounding bone showed mainly bone apposition. But experimental group showed bone resorption at anterior surface of articular eminence and increased bone apposition at posterior surface of postglenoid spine. 6. No marked traumatic change was seen but 4 weeks and 8 weeks experimental animal showed flattening of posterior surperior condylar surface. Bone marrow of condyle showed minute focal bleeding in 2 weeks and 4 weeks experimental animal, and congestion and depression of hematopoietic bone marrow during all experimental period.

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Surgical Closure of Cleft Hard Palate in a Dog (개에서 경구개열의 외과적 교정례)

  • 권영삼;장환수;장광호
    • Journal of Veterinary Clinics
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    • v.21 no.3
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    • pp.326-328
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    • 2004
  • A 7-month-old, weak female dachshund dog which had signs of cough and sneezing while eating was admitted. This case was diagnosed as cleft hard palate by the physical and blood examination. After aseptic surgical preparation, a surgical method utilizing mucoperiosteal and buccal flap technique, in which accurate apposition and secure closure was very important, was used successfully. The defect of hard palate was healed completely on 10 days after surgery without any other complication.

A RADIOGRAPHIC STUDY OF HYPERCEMENTOSIS (과백악질증에 관한 X선학적 연구)

  • Kim Si Hyun;Hwang Eui Hwan;Lee Sang Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.21 no.2
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    • pp.249-259
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    • 1991
  • The purpose of this study was to evaluate the incidence and radiographic features of 677 cases of hypercementosis by means of the analysis of full mouth periapical radiograms in 4,236 persons visited the Department of Oral Radiology, School of Dentistry, Kyung Hee University during January 1984 to December 1989. The obtained results were as follows: 1. The incidence of hypercementosis was revealed to be 8.2% in total examined persons, and there was a higher incidence in females (9.4%) than in males (7.1%). 2. The hypercementosis was most frequently occurred in the 6th decades (29.2%), and the incidence was increased by advancing age until 6th decades. 3. There was a higher incidence in the maxilla (59.5%) than in the mandible (40.5%), and maxillary second premolar (18.5%) was the most frequently involved tooth. The maxillary first premolar (11.7%) was next in order to frequency followed by maxillary canine (10.0%) and mandibular first and second premolars (9.6%). 4. In the etiologic factors, 35.0% were inflammation, 31.2% were elongation, 6.2% were trauma from occlusion, 0.1 % were uneruption, and 27.5% were unknown. 5. In the degree of cementum apposition, 35.3% were Type Ⅰ, 29.5% were Type Ⅱ, and 35.2% were Type Ⅲ. 6. In the status of cementum apposition, 3.2% were mesial side, 8.9% were distal side, and 87.9% were mesial & distal side. 7. In the identification of radiographic density between normal cementum and excessive cementum, 12.7% could be identified, and 87.3% could be unidentified.

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Short Segment Pedicle Screw Fixation with Augmented Intra-Operative Vertebroplasty in Unstable Thoraco-Lumbar Fracture - Preliminary Report - (불안정성 흉·요추부 골절에 대한 단 분절 척추경 나사못 고정술 및 추체 보강 성형술 - 예 비 보 고 -)

  • Kim, Young Woo;Oh, Sung Han;Yoon, Do Heum;Chin, Dong Kyu;Cho, Yong Eun;Kim, Young Soo
    • Journal of Korean Neurosurgical Society
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    • v.30 no.11
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    • pp.1271-1277
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    • 2001
  • Objectives : Since vertebroplasty has been introduced, we performed short segment pedicle screw fixation with augmented intra-operative vertebroplasty in patients with unstable thoraco-lumbar fracture. Our intentions are to demonstrate the efficacy and indication of this new technique compare to conventional methods. Material and Methods : The surgery comprised of pedicle screw fixations on one level above and below the fracture site, and the fractured level itself, if pedicle is intact, and intra-operative vertebroplasty under the fluoroscopic guide with in-situ postero-lateral bone graft. Also, in cases of bone apposition, we removed those with small impactor through a transfascetal route. During the last 2 years, we performed in seven(7) unstable thoraco-lumbar fracture patients who consisted of two different characteristics, those four(4) with primary or secondary osteoporosis and three(3) of young and very healthy. All patients were followed clinically by A.S.I.A. score and radiography. Results : Mean follow up period was 14 months. We observed well decompressed state via transfascetal route in cases of bone fragments apposition and no hardware pullout in osteoporotic cases, no poly-methyl-methacrylate (PMMA) leakage through the fracture sites into the spinal canal, and no kyphotic deformities in both cases during follow-up periods. All patients demonstrated solid bony fusion except one following osteoporotic compression fracture on other sites. Conclusions : In the management of unstable thoraco-lumbar fracture, we believe that this short segment pedicle screw fixation with augmented intra-operative vertebroplasty reduce the total length or levels of pedicle screw fixation without post-operative kyphotic deformity.

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Fertilization Process in Porcine Oocytes Following Intracytoplasmic Injection of Porcine, Human, Bovine or Mouse Spermatozoon (돼지, 사람, 소 및 생쥐 정자 미세주입에 의한 돼지난자의 수정과정)

  • 전수현;도정태;이장원;김남형;이훈택;정길생
    • Korean Journal of Animal Reproduction
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    • v.22 no.2
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    • pp.195-202
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    • 1998
  • We demonstrated, for the first time, pronuclear formation and apposition in porcine ooc-ytes following intracytoplasmic injection of porcine, human, bovine and mouse spermatozoon. Microtubule organization and chromatin configuration were investigated in these oocytes during pronuclear apposition. Following intracytoplasmic injection of porcine spermatozoon, the microtubular aster was organized from the neck of spermatozoon, and filled the whole cytoplasm. This male derived microtubules appear to move both pronuclei to the center of oocytes. In contrast, following injection of spermatozoa from different species such as human, bovine and mouse, microtubules were organized from the cortex of the oocytes and concentrated to the pronuclei, which seems to move both male and female pronuclei to the center of oocyte. This organization is similar to what has been shown in the parthenogenetically activated por-cine oocytes. These results suggested that the porcine, human, bovine and mouse sperm chromatin can be formed pronucleus and apposited in the center of oocytes in the absence of male derived microtubule when they were injected into porcine oocytes.

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Comparison of Continuous Appositional Suture Patterns for Cystotomy Closure in Ex Vivo Swine Model

  • Sang-hun Park;Joo-Myoung Lee;Hyunjung Park;Jongtae Cheong
    • Journal of Veterinary Clinics
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    • v.39 no.6
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    • pp.353-359
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    • 2022
  • Several suture patterns can be used for cystotomy closure, and a continuous suture pattern is the most commonly used. In this study, the fluid-tight ability and other suitabilities of continuous appositional sutures, such as the simple continuous suture pattern (SC), running suture pattern (RN), and Ford interlocking suture pattern (FI), were compared for cystotomy closure. Cystotomy closure was performed using each suture method in 10 cases of ex vivo swine bladders in each group. Suture time, leakage site, suture length, bursting pressure (BP), bursting volume (BV), and circular bursting wall tension (CBWT) were measured. Suture time and suture length were the shortest in RN and the longest in FI. Leakage occurred in two places: the incision line directly and the hole made by the suture. Leakage occurred through the incision line in 4 bladders of the RN group and 2 bladders of the FI group, but not in the SC group, and in the rest of the bladders, leakage occurred through the suture hole. The values of BP, BV, and CBWT increased in the order of FI, SC, and RN. Suture time and suture length can be considered as factors related to healing and side effects. In this study, leakage through the incision was found in a less appositional area; therefore, leakage through the hole could be considered an indicator of better apposition. Good apposition is one of the conditions required for ideal cystotomy closure. The bursting strength representing the fluid-tight ability can be expressed as the CBWT. RN is expected to be efficient and cause a small degree of foreign body reaction; however, it is expected to be less stable. FI has the greatest fluid-tightness ability, but it has been proposed that side effects due to foreign body reactions most frequently occur in FI. In conclusion, SC, which is expected to have a sufficient degree of fluid-tightness and appropriate recovery, is preferable to other continuous appositional suturing methods for cystotomy closure.