• Title/Summary/Keyword: posterior attachment

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The Comparison between the success rates of single implants replacing the mandibular first and second molar (하악 제1, 2 대구치를 대체하는 단일 임프란트 간의 성공률 비교)

  • Lee, Hang-Bin;Paik, Jung-Won;Kim, Chang-Sung;Choi, Seong-Ho;Lee, Keun-Woo;Cho, Kyoo-Sung
    • Journal of Periodontal and Implant Science
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    • v.34 no.1
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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.

Toxic Algal Bloom Caused by Dinoflagellate Alexandrium tamarense in Chindong Bay, Korea

  • Yoo Jong Su;Fukuyo Yasuwo;Cheun Byeungsoo;Lee Sam Geun;Kim Hak Gyoon
    • Fisheries and Aquatic Sciences
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    • v.3 no.1
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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 2×106 cellsl1 to 5×106 cells·l1. Water temperature varied from 11.8 to 12.3C. Toxicity of A. tamarense during red tide was measured as 8.8×105. MUcell1 by mouse bioassay.

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EXPERIMENTAL STUDY ON THE ANTERIORLY DISPLACED TEMPOROMANDIBULAR JOINT MENISCUS IN RABBIT (실험적으로 전방이동시킨 가토의 악관절원판에 관한 연구)

  • Choi, Nack-Jun;Chang, Young-Il
    • The korean journal of orthodontics
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    • v.21 no.1 s.33
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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.

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Cross Leg Flap Using Septocutaneous Flap and Cast Immobilization (중격피부 피판과 석고붕대 고정을 이용한 하지 교차 피판술)

  • Choi, Soo-Joong;Yoon, Tae-Kyung;Lee, Young-Ho;Lee, Eung-Joo;Chang, Ho-Guen;Chang, Jun-Dong
    • Archives of Reconstructive Microsurgery
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    • v.7 no.2
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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.

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Study on Osteological Characteristics of Acanthorhodeus gracilis (가시납지리 (Acanthorhodeus gracilis)의 골격학적 연구(硏究))

  • Kim, Ik-Soo;Kim, In-Ja
    • Korean Journal of Ichthyology
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    • v.10 no.2
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    • pp.231-240
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    • 1998
  • The characteristics of cranium, vertebral column and fin supports of Acanthorhodeus gracilis were examined. The fish did not have a fontanell in cranium nor process of supraethmoid. It had double orbitosphenoids and a basioccipital process developed from anterior portion of basioccipital. It had a high and triangular dorsal process on supraoccipital. In the urohyal, hypohyal attachment was bifurcated and horizontal and vertical plate were in an elongated rhombus shape with posterior edge pointed. It had teeth of 1-rowed, 5/5 and 4 free teeth. The fish did not have a coracoid foramen on shoulder girdle. It does not have a uroneural on ural centrum. It had a long and slender posterior process of pelvic bone. It had a large and flat supraneural. The fish had 14 or 15 interneural spines, of which the 1st, 2nd, 3rd and 4th had single basiosts and the rest had double basiosts. It had 11 or 12 interhemal spines, of which the 1st, 2nd, 3rd and 4th had single basiosts and the rest had double basiosts.

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Torque control during lingual anterior retraction without posterior appliances

  • Mo, Sung-Seo;Kim, Seong-Hun;Sung, Sang-Jin;Chung, Kyu-Rhim;Chun, Yun-Sic;Kook, Yoon-Ah;Nelson, Gerald
    • The korean journal of orthodontics
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    • v.43 no.1
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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.

A modified device for intraoral radiography to assess the distal osseous defects of mandibular second molar after impacted third molar surgery

  • Ana, Faria-Inocencio;Mercedes, Gallas-Torreira
    • Imaging Science in Dentistry
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    • v.41 no.3
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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.

Trabeculae in the basilar venous plexus: anatomical and histological study with application to intravascular procedures

  • Viktoriya S. Grayson;Mitchell Couldwell;Arada Chaiyamoon;Juan J. Cardona;Francisco Reina;Ana Carrera;Erin P. McCormack;Kendrick Johnson;Sassan Keshavarzi;Joe Iwanaga;Aaron S. Dumont;R. Shane Tubbs
    • Anatomy and Cell Biology
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    • v.56 no.4
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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.

A Comparative Study on the Retention of Implant Overdenture According to the Shape and the Number of Magnetic Attachment (자성 어태치먼트의 형태와 수에 따른 하악 임플란트 피개의치의 유지력에 대한 비교 연구)

  • Seo, Min-Ji;Lee, Joon-Seok;Cho, In-Ho
    • Journal of Dental Rehabilitation and Applied Science
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    • v.24 no.2
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    • pp.169-181
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    • 2008
  • The aim of this study was to compare the retention and stability of implant overdenture according to the shape and the number of magnetic attachment. The experimental groups were designed for the number of implants(1, 2, 4) and shape of magnetic attachments(flat, cushion, dome type) resulting in 9 subgroups. 45 attachments were tested attached to Br\aanemark system implants which were planted on a mandibular model. Each attachment was composed of the magnet assembly embedded in a overdenture sample and the abutment keeper screwed into the implants. Dislodging tensile forces were applied to the overdenture samples using an Instron(cross-head speed 50.80mm/min) in 3 directions simulating function: vertical, oblique, and anterior-posterior. The loading was repeated 10 times in each direction for 45 samples. The values of maximum dislodging force of each subgroup were processed statistically using SPSS V. 12.0 at the 0.05 level of significance. The results of this study were as follows: 1. Flat type magnetic overdenture was the most retentive when subjected to vertically directed forces and dome type was the lest retentive when subjected to obliquely directed forces(p<0.05). 2. In case of planting one implant, flat type had a higher vertically retentive force than anterior-posteriorly retentive force. In case of planting two implants, flat type and dome type had a higher vertically retentive force and in case of planting four implants, flat type and cushion type had a higher vertically retentive force than anterior-posteriorly retentive force(p<0.05). 3. The incremental number of dental implant, without regards to the three types of magnetic attachment shapes, showed higher retention of overdenture(p<0.05). From the results, if a patient need much more retention of implant overdenture, flat type magnetic overdenture would be a good treatment. In case of the bruxism where excessive lateral forces are already present, dome type could be expected to produce better results. In case of planting one implant, flat type is more stable than the other shape of magnet and in case of two implant, flat type and dome type are more stable and in case of four implants, flat type and cushion type are more stable. Planting more than two implants and using flat type magnetic attachment would provide better retention and stability of implant overdenture

Surgery for Entrapments of the Thoracic Outlet (흉곽 출구 포착성 신경 병증의 외과적 치료)

  • Chung, Hwan-Yung
    • Archives of Reconstructive Microsurgery
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    • v.8 no.1
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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.

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