• The korean journal of orthodontics
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• v.25 no.5 s.52
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• pp.641-654
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• 1995

The purpose of this report is to present the cause and treatment of posterior open bite. Posterior open bite is the open bite limited to posterior teeth. These problem usually are attributed to a mechanical interference with the eruption process, either ankylosis or some soft tissue interference. But, in some patient, lateral open bite is due to a disturbance of the eruptive mechanism itself and other disease or side effect following other treatment. Distinguising cause of posterior open bite, lack of eruption due to some external interference with eruption or primary failure of eruption mechanism, is important clinically because this determines the prognosis for orthodontic treatments. The characteristics, differential diagnosis with posterior open bite due to other etiologies and the treatment of these problems are presented and discussed,.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.1
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• pp.115-120
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• 2015

PURPOSE: Vertebrobasilar insufficiency (VBI) should be carefully assessed in patient for whom manipulation of the cervical spine is to be undertaken. The purpose of this study was to investigate the changes in posterior cerebral artery blood flow velocity following head and body positioning by transcranial doppler ultrasonography (TCD) in healthy subjects. METHODS: Twenty two healthy female (mean age $20.77{\pm}1.30yrs.$) participants volunteered to participate in the study. None of the participants had a history of neck pain or headache within the last 6 months. To evaluate the cerebral blood flow, we measured the mean flow velocity of the posterior cerebral artery unilaterally (right side). The blood flow velocity was measured under 3 different head positions (in a neutral head position, ipsilateral head rotation and contralateral head rotation position) and 2 different body conditions (supine position and sitting position). RESULTS: The mean blood flow velocity of posterior cerebral artery was decreased in body positioning from supine to sitting (p<.05), but the decreased rate of blood flow velocity in posterior cerebral artery did not change significantly between ipsilateral head rotation and contralateral head rotation (p>.05). CONCLUSION: These result of our study show that body positioning (sitting and supine) affect the blood flow velocity in posterior cerebral artery.

• Journal of Korean Neurosurgical Society
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• v.52 no.1
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• pp.21-26
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• 2012

Objective : To evaluate a new posterior atlantoaxial fixation technique using a nitinol shape memory loop as a simple method that avoids the risk of vertebral artery or nerve injury. Methods : We retrospectively evaluated 14 patients with atlantoaxial instability who had undergone posterior C1-2 fusion using a nitinol shape memory loop. The success of fusion was determined clinically and radiologically. We reviewed patients' neurologic outcomes, neck disability index (NDI), solid bone fusion on cervical spine films, changes in posterior atlantodental interval (PADI), and surgical complications. Results : Solid bone fusion was documented radiologically in all cases, and PADI increased after surgery (p<0.05). All patients remained neurologically intact and showed improvement in NDI score (p<0.05). There were no surgical complications such as neural tissue or vertebral artery injury or instrument failure in the follow-up period. Conclusion : Posterior C1-2 fixation with a nitinol shape memory loop is a simple, less technically demanding method compared to the conventional technique and may avoid the instrument-related complications of posterior C1-2 screw and rod fixation. We introduce this technique as one of the treatment options for atlantoaxial instability.

• Journal of Korean Foot and Ankle Society
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• v.21 no.2
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• pp.70-74
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• 2017

Fractures and fracture-dislocations of the ankle are caused by a variety of mechanisms. In addition to fractures, injuries of soft tissue, such as ligaments, tendons, nerves, and muscles may also occur. Among these, a tibialis posterior tendon injury is difficult to be identified due to swelling and pain at the fracture site. It is difficult to observe tibialis posterior tendon injury on a simple radiograph; it is usually found during surgery by accident. There are some studies regarding irreducible ankle fracture-dislocations due to interposition of the tibialis posterior tendon; however, to the best of our knowledge, there has not been any report about interposition of injured tibialis posterior tendon. Herein, we report a case of an irreducible fracture-dislocation of the ankle due to injured tibialis posterior tendon interposition that was observed intraoperatively, interrupting the reduction of ankle fracture-dislocation. We obtained satisfactory clinical result after reduction of the trapped tendon, fracture reduction, and internal fixation; therefore, we are willing to report this case with the consent of the patient. This study was conducted with an approval from the local Institutional Ethics Review Board.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.26 no.2
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• pp.153-163
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• 1996

The purpose of this study was to evaluate the ability of radiographs in detecting experimental bony defect in the posterior wall of the maxillary sinus. For this study, experimentally five skulls were used, the bony defects with a diameter of 5mm were created at different locations in the posterior wall of the right maxillary sinus and the bony defects of 10mm were created at different locations in the posterior wall of th maxillary sinus. Panoramic view, panoramic sinus view, water's view, and computed tomogram were taken and the results analyzed. The obtanined results were as follows: 1. The panoramic view was superior to the panoramic sinus view in detecting the bony defects in the posterior wall of the maxillary sinus. 2. Panoramic view, panoramic sinus view, and waters's view were limitation to the detection of the bony defects in the posterior wall of the maillary sinus. 3. All the bony defects in the posterior wall of the maxillary sinus were excellently visualized on the computed tomogram.

• Restorative Dentistry and Endodontics
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• v.12 no.2
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• pp.33-44
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• 1987

The use of composite resin for the posterior teeth gives rise to clinical problem due to the lack of mechanical properties. The purpose of this study was to observe the fractured surfaces of light posterior composite resins which are P-10, Clearfil posterior, Adaptic anterior & posterior, P-30, Lite-fil posterior, Estilux posterior, Helio-molar, and Ful-fil com pules (Table 1). The failure of composite resin specimens of I, T and Y-Type (Fig. 1,2) occured under compression. Fractographical observations by SEM (JSM-T20, JEOL) were carried out in order to examine the fracture behaviour of eight composite resins in different types of specimens. The results obtained from this study were as follows: 1. Similar features were found in fractured surfaces of eight composite resins. 2. The crack growth was initiated at the regions of porosities. 3. The crack propagated on the filler-matrix interface. 4. As the crack increased in size, it accelerated to form secondary crack. 5. The fracture behaviour was dependent on the content, size, shape, and distribution of fillers.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.20.1-20.7
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• 2020

Background: Anterior open bite is a challenging malocclusion to correct orthodontic treatment. Anterior open bite associated with over-erupted posterior teeth and long lower facial height should be treated by reduction of posterior dimension for esthetic results. Although the possibility of orthodontic treatment of an anterior open bite has increased with the introduction of skeletal anchorage, there are still cases requiring surgery for various reasons. Case presentation: This case report covers an anterior open bite of a 25-year-old man successfully treated with the posterior maxillary segmental osteotomy (PMSO) and miniplates. After the pre-surgical orthodontic treatment, the PMSO between canines and first premolars was performed under local anesthesia and miniplates were placed on the zygomatic buttress. As a result of 28 months of treatment, an impaction amount of 3.5 mm was obtained in the maxillary posterior teeth, and the facial esthetics improved at rest and smile. Conclusion: The impaction of the posterior dentoalveolar segment using the PMSO can be a good treatment option in patients with anterior open bite showing long lower facial height.

• Clinics in Shoulder and Elbow
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• v.24 no.3
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• pp.141-146
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• 2021

Background: The purpose of the present study was to determine how long superior screws alone or in combination with posterior placement of metaglene screws protruding and penetrating into the scapular spine in reverse total shoulder arthroplasty affect the strength of the scapular spine in a fresh cadaveric scapular model. Methods: Seven fresh cadaver scapulas were allocated to the control group (short posterior and superior screws) and seven scapulars to the study group (spine base fixation with a four long screws, three with both long superior and long posterior screws). Results: The failure load was lower in the spine fixation group (long screw, 869 N vs. short screw, 1,123 N); however, this difference did not reach statistical significance (p>0.05). All outside-in long superior or superior plus posterior screws failed due to scapular spine base fracture; failures in the short screw group were due to acromion fracture. An additional posterior outside-in screw failed to significantly decrease the failure load of the acromion spine. Conclusions: The present study highlights the significance of preventing a cortical breach or an outside-in configuration when a superior or posterior screw is inserted into the scapular spine base.

• Journal of Korean Neurosurgical Society
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• v.52 no.3
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• pp.240-242
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• 2012

The anterior choroidal artery has several kinds of variations. Among them, the transposition of anterior choroidal artery and posterior communicating artery origins has been extremely rare. We report a case with cerebral aneurysm arising from posterior communicating artery which origin was distal to the anterior choroidal artery and review the relevant literature.

• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.68-71
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• 1998

Ganglion cysts of the cruciate ligaments of the knee are rare and their pathogenesis is uncertain. A few cases of the cyst of the posterior cruciate ligament were reported in the literature. We have arthroscopically treated sucessfully the ganglion cysts of the posterior cruciate ligament through the anteromedial portal. We reported three cases of ganglion cyst of the posterior cruciate ligament with brief of literatures.