• 한국정밀공학회지
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• 제15권7호
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• pp.91-97
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• 1998

The analysis model is the infinite body consisted of power law creep material containing a rigid inclusion with line crack shape subjected to the arbitrarily directional stress on an infinite boundary. The crack analysis is performed using the complex pseudo-stress function. The strain rate intensity factor is determined in the closed form as new fracture mechanics parmeter which represents the magnitudes of stress and strain rate near the tip in power law creep material.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.301.1-301.1
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• 2002

The aim of present study was to investigate effects of blunt trauma on alterations in cytochrome P-450 (CYP)-dependent drug metabolizing function and to determine the role of Kupffer cells in the hepatocellular dysfunction Rats underwent closed femur fracture (FFx) with associated soft-tissue injury under anesthesia. Control animals received only anesthesia. To deplete Kupffer cells in vivo, gadolinium chloride (GdCl3) was injected intravenously via the tail vein at 7.5 mg/kg body wt. 1 and 2 days before surgery. (omitted)

• Hip & pelvis
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• 제35권3호
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• pp.183-192
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• 2023

Purpose: This study aims to determine which intertrochanteric (IT) hip fracture and patient characteristics predict the necessity for adjunct reduction aides prior to prep and drape aiming for a more efficient surgery. Materials and Methods: Institutional fracture registries from two academic medical centers from 2017-2022 were analyzed. Data on patient demographics, comorbidities, fracture patterns identified on radiographs including displacement of the lesser trochanter (LT), thin lateral wall (LW), reverse obliquity (RO), subtrochanteric extension (STE), and number of fracture parts were collected, and the need for additional aides following traction on fracture table were collected. Fractures were classified using the AO/OTA classification. Regression analyses identified significant risk factors for needing extra reduction aides. Results: Of the 166 patients included, the average age was 80.84±12.7 years and BMI was 24.37±5.3 kg/m². Univariate regression revealed increased irreducibility risk associated with RO (odds ratio [OR] 27.917, P≤0.001), LW (OR 24.882, P<0.001), and STE (OR 5.255, P=0.005). Multivariate analysis significantly correlated RO (OR 120.74, P<0.001) and thin LW (OR 131.14, P<0.001) with increased risk. However, STE (P=0.36) and LT displacement (P=0.77) weren't significant. Fracture types 2.2, 3.2, and 3.3 displayed elevated risk (P<0.001), while no other factors increased risk. Conclusion: Elderly patients with IT fractures with RO and/or thin LW are at higher risk of irreducibility, necessitating adjunct reduction aides. Other parameters showed no significant association, suggesting most fracture patterns can be achieved with traction manipulation alone.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권1호
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• pp.99-107
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• 2008

Objective : The objective of this review was to provide reliable comparative results regarding the effectiveness of any interventions either open or closed that can be used in the management of fractured mandibular condyle Patients and Methods : Research of studies from MEDLINE and Cochrane since 1990 was done. Controlled vocabulary terms were used. MeSH Terms were "Mandibular condyle" AND "Fractures, bone". Only comparative study were considered in this review using the "limit" function. According to the criteria, two review authors independently assessed the abstracts of studies resulting from the searches. The studies were divided according to some criteria, and following were measured: Ramus height, condyle sagittal displacement, condyle Towns's image displacement, Maximum open length, Protrusion & Lateral excursion, TMJ pain, Malocclusion, and TMJ disorder. Results : Many studies were analyzed to review the post-operative result of the two methods of treatment. Ramus height decreased more in when treated by closed reduction as opposed to open reduction. Sagittal condyle displacement was shown to be greater in closed reduction. Condyle Town's image condyle displacement had greater values in closed reduction. Maximum open length showed lower values in closed reduction. In protrusive and lateral movement, closed reduction was less than ORIF. Closed reduction showed greater occurrence of malocclusion than ORIF. However, post-operative pain and discomfort was greater in ORIF. Conclusion : In almost all categories, ORIF showed better results than CRIF. However, the use of the open reduction method should be considered due to the potential surgical morbidity and increased hospitalization time and cost. To these days, Endoscopic surgical techniques for ORIF (EORIF) are now in their infancy with the specific aims of eliminating concern for damage to the facial nerve and of reducing or eliminating facial scars. Before performing any types of treatment, patients must be understood of both of the treatment methods, and the best treatment method should be taken on permission.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권1호
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• pp.31-34
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• 2009

Purpose: This study compared the frequency of postoperative infections in patients for a closed mandibular fracture with that without the postoperative antibiotic prophylaxis. Patients and Methods: 48 patients without any specific medical history were divided into two groups depending on whether or not antibiotics had been applied after the surgery. The 24 patients in group 1 received only a second-generation cephalosporin ($Cefotetan^{(R)}$) intravenously from admission to immediate after the surgery. Likewise, 24 patients in group 2 received 1.0g of $Cefotetan^{(R)}$ twice daily longer than the third day after surgery. The mean (SD) duration of antibiotics administration after surgery was 6.9 (${\pm}3.56$). The patients were evaluated after surgery for any postoperative infections according to the criteria: purulent drainage from a wound, spontaneous wound dehiscence accompanied by swelling, pain, and fever around the wound. Results: Postoperative infections were encountered in 2 out of 24 patients in group 1, who received antibiotic medication until shortly after surgery, and in 3 out of the 24 patients in group 2, in whom the medication was continued even after the surgery. There was no sig nificant difference in the incidence of postoperative infections between the two groups. Conclusion: From this study, postoperative use of antibiotics seems to be unnecessary with view of the little significance of the factors that could affect the wound infection.

• 한국생산제조학회지
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• 제24권5호
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• pp.553-560
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• 2015

Fracture mechanics analysis for cracked pipes is essential for applying the leak-before-break (LBB) concept to nuclear piping design. For LBB assessment, crack instability and leak rate should be predicted accurately for through-wall cracked pipes. In a nuclear piping system, elbows are connected with straight pipes by circumferential welding; this weld region is often considered a critical location. Hence, accurate crack assessment is necessary for cracks in the interface between elbows and straight pipes. In this study, the stress intensity factor (SIF) and elastic crack opening displacement (COD) were estimated through detailed 3D elastic finite element (FE) analyses. Based on the results, closed-form solutions of shape factors for calculating the SIFs and elastic CODs were proposed for circumferential through-wall cracks in the abovementioned interfaces under internal pressure. In addition, the effect of the elbow on shape factors was investigated by comparing the results with the existing solutions for a straight pipe.

• Archives of Plastic Surgery
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• 제39권6호
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• pp.612-617
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• 2012

Background Packing after closed reduction of a nasal bone fracture causes inconvenient nasal obstruction in patients. We packed the superior meatus with Vaseline gauze to support the nasal bone, and packed the middle nasal meatus with a Doyle Combo Splint consisting of an airway tube, a silastic sheet, and an expandable sponge to reduce the inconvenience. In addition, we aimed to objectively identify whether this method not only enables nasal respiration but also sufficiently supports the reduced nasal bone. Methods Nasal ventilation was measured via spirometry 1 day before surgery and compared to 1 day after surgery. To compare support of the reduced nasal bone by the 2 methods, 2 plastic surgeons assessed the displacementon X-rays taken after the surgery and after removing the packing. The extent of nasal obstruction, dry mouth, sleep disturbance, headache, and swallowing difficulty were compared with visual analog scales (VAS) on a pre-discharge survey. Results In the experimental group, the nasal respiration volume 1 day after surgery remained at $71.3%{\pm}6.84%$ on average compared to 1 day prior to surgery. Support of the reduced bone in the experimental group ($2.80{\pm}0.4$) was not significantly different from the control group ($2.88{\pm}0.33$). The VAS scores for all survey items were lower in the experimental group than in the control group, where a lower score indicated a lower level of inconvenience. Conclusions The nasal cavity packing described here maintained objective measures of nasal respiration and supported the reduced bone similar to conventional methods. Maintaining nasal respiration reduced the inconvenience to patients, which demonstrates that this packing method is useful.

• Archives of Plastic Surgery
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• 제36권2호
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• pp.242-246
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• 2009

Purpose: The majority of nasal bone fractures have been managed by routine procedure of closed reduction and intranasal packing. However, nasal packing can cause nasal injury, hypoxia and patient's discomfort. And, synechiae formation is a frequently occurred after the nasal surgery. Various methods are used to reduce the incidence of synechiae formation. The purpose of this study was to compare routine procedure and nasal packing with reverse "U" shaped silicone sheet with respect to postoperative nasal synechiae formation and final outcome. Methods: We analyzed the medical records of 100 patients with nasal bone fracture who were operated by closed reduction in the last one year. The silicone sheet was designed in reverse "U" fan - shape and inserted between the middle turbinate and the septal wall. Nasal packing was removed at two days after the operation, and silicone sheet was removed at 10 to 14 days. Results: Synechiae in the middle meatus developed in 2 of 75 patients. Although synechiae between the middle meatus and nasal septum occurred in patients, the patients did not complaint of any olfactory disturbance and nasal obstruction. Conclusion: The reverse "U" fan - shape silicone sheet caused less pain for patients and no significant differences in outcome were found. The results of this study suggest that insertion of silicone sheet between the middle meatus and septum can be a useful method in the prevention of intranasal synechiae formation. The reverse "U" silicone sheet is a good alternative for routine packing methods.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권3호
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• pp.135-139
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• 2014

This following case report describes the open reduction, internal fixation and the reconstruction of an extensive comminuted mandibular fracture with bilateral condylar fractures in a 19-year-old male patient with an intellectual disability and autistic disorder. He suffered fall trauma, resulting in shattered bony fragments of the alveolus and mandibular body between both mandibular rami, the fracture of both condyles and the avulsion or dislocation of every posterior tooth of the mandible. The patient underwent open reduction and internal fixation between both mandibular rami using a reconstruction plate, open reduction and internal fixation of the shattered fragments using miniplates and screws, and the closed reduction of the bilateral condylar fractures.

• 대한두개안면성형외과학회지
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• 제10권1호
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• pp.33-36
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• 2009

Purpose: Fractures of the mandibular condylar area are common injuries that account for 29% to 40% of fractures of the facial bones and represent 20% to 62% of all mandibular fractures. Currently 3 main methods are being used in the treatment of mandibular subcondylar fractures: closed reduction; open reduction and internal fixation; Endoscopic reduction and internal fixation. Each method has its proponents and opponent as well as advantages and disadvantages, and indications for each vary among surgeons. There are six approaches of open reduction: submandibular, retromandibular, preaurilcular, postauricular, intraoral, transparotid approach. Among them, transparotid approach has been described for subcondylar exposure with dissection in the direction of facial nerve fibers to expose the bone through the parotid gland. This approach carries the risk of a parotid glandular fistula as well as facial nerve injury but has the advantage of being directly over the fracture site. We report safety and efficacy of surgical treatment using a transparotid approach for direct plating. Methods: A 43-year-old man sustained multiple facial bone fractures by driver traffic accident. Mandibular subcondyle was fractured and dislocated internally. We performed open reduction and internal fixation by transparotid approach. Fractured site was fixed by titanium mini plate & screw. We applicated arch bar for approximately 3 weeks. Results: Follow-up length was about 5months. Scar of surgical incision was indistinct, there was no symptoms and signs of facial nerve and parotid gland injury, and maximal mouth opening was measured 49.5 mm. Conclusion: Transparotid approach has high risks of facial nerve and parotid gland injury, but paradoxically it is the most effective technique in saving facial nerve. Open reduction and internal fixation of mandibular subcondylar fracture by transparotid approach with precise and versed procedure, best outcome can be expected.