• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.101-112
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• 2004

Osseointegrated implnats have proven to be successful in both full and partial edentulous patients since the 1960s and recently have shown successful results when used to restore single tooth missing. However, in most studies reporting the success of single implants, single implants replacing anterior teeth are more frequently mentioned than posterior single implants. Moreover, in studies regarding posterior single implants, the replaced region seemed to be variable; the maxilla, mandible and areas from the first premolar to the second molar were mentioned. However, considering the difference in bone quality in the mandible and maxilla, and the increased occlusal force in the posterior region, the success rates in each region may be different. In this study, the cumulative success rates and amount of bone loss of single implants replacing the mandibular first and second molar, respectively, were compared and analyzed to come to the following conclusion. 1. The 20 (20 persons) single implants that were placed in the mandibular first molar region were all successful and showed a 100% 5 year cumulative success rate. Among the 27 (24 persons) single implants replacing the mandibular second molar, 8 failed (27.63%) showing a 5 year cumulative success rate of 70.37%. 2. Among the 8 failed implants, one showed symptoms of postoperative infection and one complained of parenthesia. 6 implants failed after functional loading; 5 showed mobility and one resulted in fixture fracture. 3. After the attachment of the prosthesis, there was no significant statistical difference regarding the marginal bone loss in group 1 and group 2 during the checkup period (P>0.05). In conclusion, restoration of the mandibular first molar using single implants was found to be an excellent treatment modality, and when replacing mandibular second molars with single implants, poor bone quality and risk of overloading must be considered.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.26-32
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• 2000

Monospecific red tide by a toxic dinoflagellate belonging to the genus Alexandrium occurred at Chindong Bay in the southern coast of Korea and continued from April 6th to 15th in 1997. The ratio of its cell number to total phytoplankton cell number was much higher than $95\%$. This organism was identified as Alexandrium tamarense, although slight morphological differences were found comparing to the original and successive descriptions of the species. We found neither anterior nor posterior attachment pores in these cells of the bloom population. The occurrence of red tide caused by A. tamarense was first reported in Korea. Its plate formula is Po, Pc, 4', 6"c, 8s, 5"' and 2"". Thecal plates are thin with pore-like ornamentation. In those plates, the anterior part of the first apical plate (1') is narrower and its posterior end has sometimes a block-like accessory, but this variation was considered within the range of the morphological variability of this taxon. The cell density during the red tide exhibited a wide range of variation by the depth of water column, ranging from $2\times10^6$ cells$l^{-1}$ to $5\times10^6$ cells·$l^{-1}$. Water temperature varied from 11.8 to $12.3^{\circ}C$. Toxicity of A. tamarense during red tide was measured as $8.8\times10^5$. $MU\;\cdot\;cell^{-1}$ by mouse bioassay.

• 대한치과교정학회지
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• 제21권1호
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• pp.53-76
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• 1991

The study was designed to analyse the reorganization of the rabbit TMJ meniscus which was anteriorly displaced by surgery. The author compared the anteriorly displaced groups with control group. After surgical opening of the left rabbit TMJ space, cut the posterior attachment of the meniscus, and pushed it under the undercut area of the condyle head. Experimental groups were sacrificed by 1, 2, 4, 8 weeks after surgery. The samples were analysed with light microscope under T-B stain and electron microscope. The results were as follows: 1) The rabbit TMJ meniscus consisted of thick anterior and posterior band running different way, and comparative thin intermediate band runining antero-posteriorly. 2) Round oval shape chondrocyte-like cells were imbeded between the collagen fiber bundles and composed of proteoglycan granules, that showed metachromasia with toluidine blue, around the cell matrix. 3) Type II collagen fiber bundles in experimental group occured degenerative changes in organic patterns at 8 weeks, but those of type I collagen fiber bundles sustained longer, 4) The typical fibrocartilage of the rabbit TMJ meniscus was changed into fibrotic mode in process of time and showed the degenerative changes, which contained hyperplasia, calcification, resorption and hyalinization in the connective tissue. 5) The hyperplastic change of the synovial membrane in 4 week group and transitional change from fibrocyte to chondrocyte in cell type in 8 week group were observed. 6) The diameters of collagen fibers were diminished with the degenerative changes, the shape of the fibers became wavier and more nonorganic in running pattern and fiber bundle spaces widened.

• Archives of Reconstructive Microsurgery
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• 제7권2호
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• pp.165-174
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• 1998

Large soft tissue defect of the ankle and foot can present a difficult reconstructive problem to the surgeon. Local musculocutaneous, local fasciocutaneous or free flap is usually the first choice for providing soft tissue coverage. However, in certain situations, local flaps from the same leg and free flap may not be suitable. These include extensive soft tissue injury, where no suitable recipient vessels can be found, previous local fasciocutaneous flap or free flap failure. In such cases, we have utilized the septocutaneous(fasciocutaneous) branch flap of posterior tibial artery from the opposite healthy limb. We present 5 cases of cross leg flaps, which have been modernized with current understanding of vascular anatomy and current fixation technology. All cross leg flaps were based on the axial blood supply of the fasciocutanous branch of the posterior tibial artery. Cross-clamping with bowel clamp was used to create intermittent periods of ischemia. Adjacent lower extremity joints were exercised during the periods of attachment. The results have been quite encouraging. We conclude that the cross leg flap using septocutaneous flap and cast immobilization can be successfully and expeditiously used to cover defects of the ante and foot.

• 한국어류학회지
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• 제10권2호
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• pp.231-240
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• 1998

납자루아과(亞科)에 속하는 가시납지리(Acanthorhodeus gracilis)의 두골(頭骨), 척주(脊柱), 지느러미 골격을 조사하였다. 두개부(頭蓋部)에 천문이 없으며, 상사골(上篩骨)의 전단에 돌기가 없고, 안와설골(眼窩楔骨)은 2개로 되어 있다. 기저후두골(基底後頭骨) 돌기(突起)는 전반부에서부터 발달하였고, 상후두골(上後頭骨)은 높은 삼각형 형태의 돌기를 갖고 있으며, 미설골(尾舌骨)은 선단(先端)이 2분기(分技)되고 수평판(水平板)과 수직판(垂直板)의 후방(後方)이 넓어지며 후연(後緣)이 돌출되어 있다. 인두치(咽頭齒)는 1열로 인두치식(咽頭齒式)은 5 - 5이며 4개의 유리치(遊離齒)를 갖고 있다. 편대(扁帶)에는 오훼골(烏喙骨) 구멍이 없으며, 미골추체(尾骨推體)에는 미신경골(尾神經骨)이 나타나지 않고, 길고 가느다란 후요대돌기(後腰帶突起)를 갖는다. 유리신경간련(遊離神經間練)은 넓은 판상(板狀)이고, 신경간극(神經間棘)은 14~15개이며 제1~제4신경간극(神經間棘)은 하나의 기기골을 나머지는 두 개의 기기골을 기부(基部)에 갖고 있고, 혈관간극(血管間棘)은 11~12개이며 제1~제 4혈관간극(血管間棘)은 하나의 기기골을 나머지는 두 개의 기기골을 갖고있다.

• 대한치과교정학회지
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• 제43권1호
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• pp.3-14
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• 2013

Objective: To evaluate the factors that affect torque control during anterior retraction when utilizing the C-retractor with a palatal miniplate as an exclusive source of anchorage without posterior appliances. Methods: The C-retractor was modeled using a 3-dimensional beam element (0.9-mm-diameter stainless-steel wire) attached to mesh bonding pads. Various vertical heights and 2 attachment positions for the lingual anterior retraction hooks (LARHs) were evaluated. A force of 200 g was applied from each side hook of the miniplate to the splinted segment of 6 or 8 anterior teeth. Results: During anterior retraction, an increase in the LARH vertical height increased the amount of lingual root torque and intrusion of the incisors. In particular, with increasing vertical height, the tooth displacement pattern changed from controlled tipping to bodily displacement and then to lingual root displacement. The effects were enhanced when the LARH was located between the central and lateral incisors, as compared to when the LARH was located between the lateral incisors and canines. Conclusions: Three-dimensional lingual anterior retraction of the 6 or 8 anterior teeth can be accomplished using the palatal miniplate as the only anchorage source. Using LARHs at different heights or positions affects the quality of torque and intrusion.

• Imaging Science in Dentistry
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• 제41권3호
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• pp.115-121
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• 2011

Purpose : This article is to describe a modified device for intraoral radiography which was developed to obtain reproducible radiographic images for assessment of distal osseous defects of the mandibular second molar (2 Mm) after impacted third molar (3 Mm) surgery. Materials and Methods : A commercial available alignment system for posterior region was modified by adding a reference gauge pin (millimetric) and threading a hollow acrylic cylinder at the ring of the radiographic positioner to attach the X-ray collimator. The design included customized resin acrylic stent for the occlusal surface of the 2Mm in maximum intercuspal position, individualizing the biteblock positioner. Periapical radiographs were taken before and after surgical extraction of 3 Mm, employing the radiographic technique of parallelism described by Kugelberg (1986) with this modified film holder and inserting the gauge pin on the deepest bone probing depth point. Results : This technique permitted to obtain standardized periapical radiographs with a moderate to high resolution, repeatability, and accuracy. There was no difference between the measurements on the pre- and post-operative radiographs. This technique allowed better maintenance of the same geometric position compared with conventional one. The insertion of the gauge pin provided the same reference point and localized the deepest osseous defect on the two-dimensional radiographs. Conclusion : This technique allowed better reproducibility in posterior radiographic records (distal surface of 2 Mm) and more accurate measurements of radiographic bone level by the use of a millimetric pin.

• Anatomy and Cell Biology
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• 제56권4호
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• pp.435-440
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• 2023

Few studies have examined the basilar venous plexus (BVP) and to our knowledge, no previous study has described its histology. The present anatomical study was performed to better elucidate these structures. In ten cadavers, the BVP was dissected. The anatomical and histological evaluation of the intraluminal trabeculae within this sinus were evaluated. Once all gross measurements were made, the clivus and overlying BVP were harvested and submitted for histological analysis. A BVP was identified in all specimens and in each of these, intraluminal trabeculae were identified. The mean number of trabeculae per plexus was five. These were most concentrated in the upper half of the clivus and were more often centrally located. These septations traveled in a posterior to anterior direction and usually, from inferiorly to superiorly however some were noted to travel horizontally. In a few specimens the trabeculae had wider bases, especially on the posterior attachment to the meningeal layer of dura mater. More commonly, the trabeculae ended in a denticulate form at their two terminal ends. The trabeculae were on average were 0.85 mm in length. The mean width of the trabeculae was 0.35 mm. These septations were consistent with the cords of Willis as are found in the lumen of some of the other intradural venous sinuses. An understanding of the internal anatomy of the BVP can aid in our understanding of venous pathology. Furthermore, this knowledge will benefit patients undergoing interventional treatments that involve the BVP.

• 구강회복응용과학지
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• 제24권2호
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• pp.169-181
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• 2008

치과용 자석의 개선으로 자성 어태치먼트를 이용한 임플란트 피개의치의 사용이 늘고 있다. 또한 여러 형태의 자성 어태치먼트가 개발되어 임상 상황에 따라 적절히 선택하여 사용할 수 있게 되었다. 이에 시중에 판매되는 세 가지 형태의 임플란트용 자성 어태치먼트를 이용해 자성 어태치먼트의 형태와 임플란트 수에 따른 임플란트 피개의치의 유지력을 비교 분석하였다. 식립된 임플란트가 1개인 경우를 1군, 2개인 경우 2군, 4개인 경우를 3군으로 하였고, 자성 어태치먼트의 형태에 따라 flat type, cushion type, dome type으로 세분하였다. Instron으로 수직방향, 사선방향, 전후방향의 인장력을 가하여 자성 어태치먼트의 형태에 따른 유지력의 차이, 힘의 방향에 따른 유지력의 차이, 자성 어태치먼트의 수에 따른 유지력의 변화를 비교 분석하여 다음의 결과를 얻었다. 1) 임플란트의 수와 상관없이 수직력은 flat type이 가장 컸으며, 측방력은 dome type이 가장 작은 것으로 나타났다. 2) 임플란트가 1개일 때 flat type의 수직력이 전후방회전력보다 크게 나타났고, 임플란트가 2개일 때는 dome type과 flat type이, 임플란트가 4개일 때는 cushion type과 flat type에서 수직력이 전후방회전력보다 크게 나타났다. 3) 임플란트 수에 따른 유지력 측정결과, 자석의 형태에 상관없이 임플란트 수가 많을수록 유지력은 증가하였다. 이상의 결과로 볼 때, 큰 유지력이 필요한 환자에게는 flat type이, 유해한 수평력이 존재하는 환자에게는 dome type의 이용이 유리하고, 임플란트가 1개일 때 flat type, 2개일 때 dome type과 flat type, 임플란트가 4개일 때 cushion type과 flat type이 피개의치의 안정성이 더 좋은 것으로 나타났다. 또한 자성 어태치먼트의 형태에 상관없이 임플란트의 수가 증가할수록 더 큰 유지력을 나타냈다. 따라서 임플란트 피개의치 사용 시 적절한 유지력과 안정성을 얻기 위해서 임플란트의 수와 자성 어태치먼트 형태의 고려가 필요하다고 사료된다.

• Archives of Reconstructive Microsurgery
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• 제8권1호
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• pp.1-9
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• 1999

Surgical treatment was performed on the 39 cases out of 76 cases of entrapments of the thoracic outlet. The remaining 36 cases of entrapments were treated by conservatively. The operated cases were categorized as follows. They were 34 cases of scalenus anticus syndrome, 1 of cervical rib syndrome, 2 of costoclavicular syndrome, and 2 of hyperabduction syndrome. 1. Scalenus anticus syndrome : Anterior scalenotomy was performed by simple sectioning of the attachment to the first rib. 2. Cervical rib syndrome : Complete decompressive resection of cervical rib sometimes required both anterior and posterior approaches to avoid over-retraction of the brachial plexus. 3. Costoclavicular syndrome : Partial decompressive claviculectomy was undergone instead of conventional total claviculectomy. 4. Hyperabduction syndrome : The resection of coracoid process was performed as well as conventional tenotomy of pectoralis minor muscle to insure free up-and-down moving of neurovascular bundle at the time of hyperabduction. Every diagnostic maneuver was tested at the time of operation to observe whether or not neurovascular decompression including restoration of radial pulse was sufficient. Despite of the postoperative vascular restoration was inmediate, neurogenic symptoms were improved slowly. Because this entity is essentially chronic nerve injnry, its recovery needed a couple of months or several. Although improvement was slow, ultimate results were definite. Complication was not observed.