• The Journal of the Korean dental association
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• v.56 no.11
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• pp.631-640
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• 2018

Nowadays computer-guided "flapless" surgery for implant placement using templates is gaining popularity among clinicians and patients. The advantages of this surgical protocol are its minimally invasive nature, accuracy of implant placement, predictability, less post-surgical discomfort and reduced time required for definitive rehabilitation. Aim of this study is to describe the digital implant protocol, thanks to which is now possible to do a mini-invasive static guided implant surgery. This is possible thanks to a procedure named surface mapping based on the matching between numerous points on the surface of patient's dental casts and the corresponding anatomical surface points in the CBCT data. With some critical points and needing an adequate learning curve, this protocol allows to select the ideal implant position in depth, inclination and mesio-distal distance between natural teeth and or other implants enabling a very safe and predictable rehabilitation compared with conventional surgery. It represents a good tool for the best compromise between anatomy, function and aesthetic, able to guarantee better results in all clinical situations.

• Imaging Science in Dentistry
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• v.50 no.4
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• pp.323-330
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• 2020

Purpose: The mastoid region is ideal for studying sexual dimorphism due to its anatomical position at the base of the skull. This study aimed to determine sex in the Iranian population based on measurements of the mastoid process using different data mining algorithms. Materials and Methods: This retrospective study was conducted on 190 3-dimensional cone-beam computed tomographic (CBCT) images of 105 women and 85 men between the ages of 18 and 70 years. On each CBCT scan, the following 9 landmarks were measured: the distance between the porion and the mastoidale; the mastoid length, height, and width; the distance between the mastoidale and the mastoid incision; the intermastoid distance (IMD); the distance between the lowest point of the mastoid triangle and the most prominent convex surface of the mastoid (MF); the distance between the most prominent convex mastoid point (IMSLD); and the intersecting angle drawn from the most prominent right and left mastoid point (MMCA). Several predictive models were constructed and their accuracy was compared using cross-validation. Results: The results of the t-test revealed a statistically significant difference between the sexes in all variables except MF and MMCA. The random forest model, with an accuracy of 97.0%, had the best performance in predicting sex. The IMSLD and IMD made the largest contributions to predicting sex, while the MMCA variable had the least significant role. Conclusion: These results show the possibility of developing an accurate tool using data mining algorithms for sex determination in the forensic framework.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.152-159
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• 2022

The role of the posterior palatal seal is important in retention of the maxillary complete denture. After taking the final impression, additional retention can be given to the maxillary denture through a mechanical method of forming a groove on master cast, but this is often overlooked in the clinical process. As a result, the posterior palatal seal is formed in a uniform way by the technician without considering the individual characteristics of the patient. Until now, various types of posterior palatal seal have been introduced by many people. This case report describes the process of manufacturing the maxillary complete denture by determining the position and form of an appropriate posterior palatal seal after considering the patient's anatomical palatal form and tissue displacement during function.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.47-52
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• 2023

In whole spine radiography using the stitching technique, overlapping parts occur in the process of synthesizing the three segmented images, so some anatomical structures may be repeatedly exposed, and it has been thought that the dose increases as the scan range increases. However, in the whole spine radiography using the stitching technique in this study, under the condition that the stitching range is taken in the same three splits, the overlapping area decreases as the stitching range increases, so in the case of breasts included in the overlapping range, the dose value decreased by almost half as the stitching range increased from 90 cm to 105 cm. During spinal full-length radiological examination using the stitching method, an appropriately long stitching range could be set to reduce the exposure dose of the breast.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.63-72
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• 2023

When oral restoration is performed with a full mouth implant-supported fixed restoration in an edentulous patient, it is very important to determine the shape and position of the definitive prosthesis in consideration of the anatomical state and the relationship with the antagonist, and the process of placing multiple implants in the planned direction and angle is very important. In this case, implants were ideally planned based on an upper prosthesis through a computer-guided surgical procedure for an edentulous maxillary patient who visited due to discomfort in the existing denture. Through this, we would like to report this because we obtained satisfactory functional and esthetic results for both the patient and the operator with the treatment of oral restoration by manufacturing a fixed prosthesis for maxillary and full jaw implants.

• Journal of Korean Neurosurgical Society
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• v.66 no.2
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• pp.183-189
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• 2023

Objective : The facial nerve trace on the ipsilateral side of the vestibular schwannoma was reconstructed by diffusion tensor imaging tractography to identify the adjacent relationship between the facial nerve and the tumor, and to improve the level of intraoperative facial nerve protection. Methods : The clinical data of 30 cases of unilateral vestibular schwannoma who underwent tumor resection via retrosigmoid approach were collected between January 2019 and December 2020. All cases underwent magnetic resonance imaging examination before operation. Diffusion tensor imaging and anatomical images were used to reconstruct the facial nerve track of the affected side, so as to predict the course of the nerve and its adjacent relationship with the tumor, to compare the actual trace of the facial nerve during operation, verify the degree of coincidence, and evaluate the nerve function (House-Brackmann grade) after surgery. Results : The facial nerve of 27 out of 30 cases could be displayed by diffusion tensor imaging tractography, and the tracking rate was 90% (27/30). The intraoperative locations of facial nerve shown in 25 cases were consistent with the preoperative reconstruction results. The coincidence rate was 92.6% (25/27). The facial nerves were located on the anterior middle part of the tumor in 14 cases, anterior upper part in eight cases, anterior lower part in seven cases, and superior polar in one case. Intraoperative facial nerve anatomy was preserved in 30 cases. Among the 30 patients, total resection was performed in 28 cases and subtotal resection in two cases. The facial nerve function was evaluated 2 weeks after operation, and the results showed grade I in 12 cases, grade II in 16 cases and grade III in two cases. Conclusion : Preoperative diffusion tensor imaging tractography can clearly show the trajectory and adjacent position of the facial nerve on the side of vestibular schwannoma, which is beneficial to accurately identify and effectively protect the facial nerve during the operation, and is worthy of clinical application and promotion.

• Clinics in Shoulder and Elbow
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• v.27 no.1
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• pp.88-107
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• 2024

The aim of this systematic review was to collect evidence on the following 10 technical aspects of glenoid baseplate fixation in reverse total shoulder arthroplasty (rTSA): screw insertion angles; screw orientation; screw quantity; screw length; screw type; baseplate tilt; baseplate position; baseplate version and rotation; baseplate design; and anatomical safe zones. Five literature libraries were searched for eligible clinical, cadaver, biomechanical, virtual planning, and finite element analysis studies. Studies including patients >16 years old in which at least one of the ten abovementioned technical aspects was assessed were suitable for analysis. We excluded studies of patients with: glenoid bone loss; bony increased offset-reversed shoulder arthroplasty; rTSA with bone grafts; and augmented baseplates. Quality assessment was performed for each included study. Sixty-two studies were included, of which 41 were experimental studies (13 cadaver, 10 virtual planning, 11 biomechanical, and 7 finite element studies) and 21 were clinical studies (12 retrospective cohorts and 9 case-control studies). Overall, the quality of included studies was moderate or high. The majority of studies agreed upon the use of a divergent screw fixation pattern, fixation with four screws (to reduce micromotions), and inferior positioning in neutral or anteversion. A general consensus was not reached on the other technical aspects. Most surgical aspects of baseplate fixation can be decided without affecting fixation strength. There is not a single strategy that provides the best outcome. Therefore, guidelines should cover multiple surgical options that can achieve adequate baseplate fixation.

• Anatomy and Cell Biology
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• v.57 no.3
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• pp.378-383
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• 2024

The 7th cervical vertebra (C7) is described as having the most prominent spinous process (SP) and is characterized as the "vertebra prominens" (VP) of the cervical spine in anatomy textbooks. The VP is an important anatomical landmark of the neck for clinical examination and therapeutic intervention. The present study identifies the level of the most prominent SP of the cervical and uppermost thoracic vertebrae in a cadaveric cohort. Thirty-nine (23 female and 16 male) cadavers of a mean age of 77.5 years were investigated in a prone position and a certain cervical kyphotic bending. The most prominent SP, at the base of the neck, was palpated and marked with a wedging nail into the SP of the vertebra. The cervical region was dissected, and a blind investigator examined whether the nail was placed into the SP of C7 or the SP of another upper or lower vertebra. In 19 out of 39 cadavers (48.7%), the C7 was identified as the VP (typical anatomy), followed by the C6 (in 14 cadavers, 35.9%), C5 (in 4 cadavers, 10.3%). In 2 cadavers (5.1%) the first thoracic vertebra was identified as having the most prominent SP. Although C7 is described as the VP, in the present study the SP of C7 was the most prominent in less than 50%. The high variable projection level of the most prominent SP of the cervical vertebra holds great clinical significance for spine examination, neck surgery, and spinal anesthesia.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.4 no.1
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• pp.1-9
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• 2001

Purpose: Gastroesophgeal reflux (GER) is defined as involuntary movement of gastric contents into esophagus. Relaxation of lower esophageal sphincter caused by immature anatomical development in newborn and young infants produces GER frequently. We wanted to know whether the frequency of GER is influenced by feeding types and position or not. We studied in 16 subjects according to feeding types (breast feeding group: BFG-7, formula feeding group: FFG-9) who admitted to the Soonchunhyang university hospital for recurrent regurgitation with 24 hr esophageal pH monitoring from August 1996 to July 1999. Methods: We compared two groups by number of reflux episode, reflux rate, longest episode, numbers of episodes lasting >5 minutes, longest episode in upright position and longest episode in supine position. We used Mann-Whitney test for statistical analysis. Results: 1) The subjects were 7 infants in BFG and 9 infants in FFG, 16 in total, and mean age was 2.1, and 2.6 months for BFG and FFG, respectively. 2) The reflux numbers were $244{\pm}151/day$, $275{\pm}155/day$ for BFG and FFG, respectively. 3) The reflux rate was $14{\pm}15%$ for BFG and $28{\pm}22%$ for FFG. It was lower in BFG. 4) The longest episode was $20{\pm}28$ minutes for BFG and $58{\pm}66$ minutes for FFG. It was significantly longer in FFG. 5) The numbers of episodes lasting >5 minutes were $5{\pm}6$ for BFG and $9{\pm}3$ for FFG. 6) The longest episode in upright position was $10{\pm}8$ minutes for BFG and $40{\pm}47$ minutes for FFG. It was significantly shorter in BFG. 7) The longest episode in supine position was $18{\pm}29$ minutes for BFG and $52{\pm}66$ minutes for FFG. It was significantly shorter in BFG. Conclusion: Breast feeding is strongly recommended to reduce the regurgitation in infancy. It is an another benefit of breast feeding.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.11-22
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• 1985

Femur neck fracture is well known as one of the major death cause after trauma in elderly patients, and unsolved fracture due to its frequent association with complications such as avascular necrosis and nonunion. Through meticulous evaluation of the patient, hip and surgeon's experiences, reduction of mortality and morbidity as well as rapid recovery of the patient to the preinjury social and ambulatory status without local complications and revision after treatment is urgently needed. Many factors about this fracture In itself were noted, but we have analyzed 18 femur neck fractures of the patients older than 50 years preliminarily according to age, fracture pattern, osteoporosis, etiology and method of treatment with its delay in association with major complications especially avascular necrosis and nonunion. The results are as follows; 1. Of these 18 fractures, 11 were in females, 8 were caused by minor trauma such as slip-down accident and 4 were associated with definite osteoporosis according to the Sing's classification. 2. Fracture pattern of these 18 are undisplaced in 4, displaced subcapital in 11, displaced transcervical in 3. 11 fractures in the patients older than 60 year are composed of 3 undisplaced or impacted fractures and 8 displaced subcapital fractures. 3. These 18 fractures were treated by closed reduction and Internal fixation with multiple pins in 13, and hemiarthroplasty in 4, but one was not treated to die after discharge from hospital. 4. 4 undisplaced or impacted fractures and 3 displaced transcervical fractures were not associated with any complications such as avascular necrosis or nonunion. But 4 of 6 displaced subcapital fractures were complicated by avascular necrosis, 3 of which were reduced in the varus position within 1 week, and the other was reduced in the good position on 1 week after trauma. There was no complication in 2 displaced subcapital fractures reduced in valgus position within 3 days after trauma. According to the above results, the prognosis of the femur neck fracture is dependent upon the fracture pattern and delay in its treatment. So it is inevitable to reduce the fracture in anatomical or valgus position as early as possible. But the arthroplasty may be needed in displaced subcapital fractures delayed for several days, with its reluction in extreme varus position or impossible and with pre-existing disease in the same hip Joint (total hip replacement).