• Journal of Chest Surgery
• /
• 제54권5호
• /
• pp.400-403
• /
• 2021

A 63-year-old patient was admitted with a sternal fracture and mass. On evaluation, most of the body of the sternum had been destroyed by a tumor. Radical resection of the sternum was performed and part of the major pectoral muscles adherent to the sternal tumor was also resected. The chest wall defect was reconstructed with mesh, bone cement, and a titanium rib plate system. Reconstruction with this method seemed to be an appropriate procedure to prevent instability of the chest wall.

• 대한치과보철학회지
• /
• 제44권3호
• /
• pp.295-313
• /
• 2006

Statement of problem. Higher fracture rates were reported for Branemark implants placed in the maxilla and for 3.75 mm diameter implants installed in the posterior region. Purpose. The purpose of this study was to investigate the fracture of a fixture by finite element analysis and to compare different diameter of fixtures according to the level of alveolar bone resorption. Material and Methods. The single implant and prosthesis was modeled in accordance with the geometric designs for the 3i implant systems. Models were processed by the software programs HyperMesh and ANSA. Three-dimensional finite element models were developed for; (1) a regular titanium implant 3.75 mm in diameter and 13 mm in length (2) a regular titanium implant 4.0 mm in diameter and 13 mm in length (3) a wide titanium implant 5.0 mm in diameter and 13 mm in length each with a cementation type abutment and titanium alloy screw. The abutment screws were subjected to a tightening torque of 30 Ncm. The amount of preload was hypothesized as 650 N, and round and flat type prostheses were 12 mm in diameter, 9 mm in height were loaded to 600 N. Four loading offset points (0, 2, 4, and 6 mm from the center of the implants) were evaluated. To evaluate fixture fracture by alveolar bone resorption, we investigated the stress distribution of the fixtures according to different alveola. bone loss levels (0, 1.5, 3.5, and 5.0 mm of alveolar bone loss). Using these 12 models (four degrees of bone loss and three implant diameters), the effects of load-ing offset, the effect of alveolar bone resorption and the size of fixtures were evaluated. The PAM-CRASH 2G simulation software was used for analysis of stress. The PAM-VIEW and HyperView programs were used for post processing. Results. The results from our experiment are as follows: 1. Preload maintains implant-abutment joint stability within a limited offset point against occlusal force. 2. Von Mises stress of the implant, abutment screw, abutment, and bone was decreased with in-creasing of the implant diameter. 3. With severe advancing of alveolar bone resorption, fracture of the 3.75 and the 4.0 mm diameter implant was possible. 4. With increasing of bending stress by loading offset, fracture of the abutment screw was possible.

• 대한두개안면성형외과학회지
• /
• 제21권4호
• /
• pp.229-236
• /
• 2020

Background: Oncologic resection of the scalp confers several obstacles to the reconstructive surgeon dependent upon patient-specific and wound-specific factors. We aim to describe our experiences with various reconstructive methods, and delineate risk factors for coverage failure and complications in the setting of scalp reconstruction. Methods: A retrospective chart review was conducted, examining patients who underwent resection of fungating scalp tumors with subsequent soft-tissue reconstruction from 2003 to 2019. Patient demographics, wound and oncologic characteristics, treatment modalities, and outcomes were recorded and analyzed. Results: A total of 189 patients were appropriate for inclusion, undergoing a range of reconstructive methods from skin grafting to free flaps. Thirty-three patients (17.5%) underwent preoperative radiation. In all, 48 patients (25.4%) suffered wound site complications, 25 (13.2%) underwent reoperation, and 47 (24.9%) suffered from mortality. Preoperative radiation therapy was an independent risk factor for wound complications (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.1-7.3; p=0.028) and reoperations (OR, 4.45; 95% CI, 1.5-13.2; p=0.007). Similarly, the presence of an underlying titanium mesh was an independent predictor of wound complications (OR, 2.49; 95% CI, 1.1-5.6; p=0.029) and reoperations (OR, 3.40; 95% CI, 1.2-9.7; p=0.020). Both immunosuppressed status (OR, 2.88; 95% CI, 1.2-7.1; p=0.021) and preoperative radiation therapy (OR, 3.34; 95% CI, 1.2-9.7; p=0.022) were risk factors for mortality. Conclusion: Both preoperative radiation and the presence of underlying titanium mesh are independent risk factors for wound site complications and increased reoperation rates following oncologic resection and reconstruction of the scalp. Additionally, preoperative radiation, along with an immunosuppressed state, may predict patient mortality following scalp resection and reconstruction.

• 대한치과교정학회지
• /
• 제44권5호
• /
• pp.236-245
• /
• 2014

Objective: To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction. Methods: Thirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with preadjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed. Results: Both groups showed full retraction of the maxillary anterior teeth by controlled tipping and space closure without altered posterior occlusion. However, the preformed C-wire group had a shorter retraction period (by 3.2 months). Furthermore, the maxillary molars in this group showed no significant mesialization, mesial tipping, or extrusion; some mesialization and mesial tipping occurred in the conventional C-wire group. Conclusions: Preformed C-wires combined with maxillary TSADs enable simultaneous leveling and space closure from the beginning of the treatment without maxillary posterior bonding. This allows for faster treatment of dentoalveolar protrusion without unwanted side effects, when compared with conventional C-wire, evidencing its clinical expediency.

• Archives of Plastic Surgery
• /
• 제39권1호
• /
• pp.31-35
• /
• 2012

Background : Orbital roof fractures are frequently associated with a high energy impact to the craniofacial region, and displaced orbital roof fractures can cause ophthalmic and neurologic complications and occasionally require open surgical intervention. The purpose of this article was to investigate the clinical features and treatment outcomes of orbital root fractures combined with neurologic injuries after early reconstruction. Methods : Between January 2006 and December 2008, 45 patients with orbital roof fractures were admitted; among them, 37 patients were treated conservatively and 8 patients underwent early surgical intervention for orbital roof fractures. The type of injuries that caused the fractures, patient characteristics, associated fractures, ocular and neurological injuries, patient management, and treatment outcomes were investigated. Results : The patients underwent frontal craniotomy and free bone fragment removal, their orbital roofs were reconstructed with titanium micromesh, and associated fractures were repaired. The mean follow up period was 11 months. There were no postoperative neurologic sequelae. Postoperative computed tomography scans showed anatomically reconstructed orbital roofs. Two of the five patients with traumatic optic neuropathy achieved full visual acuity recovery, one patient showed decreased visual acuity, and the other two patients completely lost their vision due to traumatic optic neuropathy. Preoperative ophthalmic symptoms, such as proptosis, diplopia, upper eyelid ptosis, and enophthalmos were corrected. Conclusions : Early recognition and treatment of orbital roof fractures can reduce intracranial and ocular complications. A coronal flap with frontal craniotomy and orbital roof reconstruction using titanium mesh provides a versatile method and provides good functional and cosmetic results.

• 대한두개안면성형외과학회지
• /
• 제17권4호
• /
• pp.218-221
• /
• 2016

Temporal hollowing is a common complication that occurs after coronal approach surgeries. However, temporal hollowing without previous nerve damage or trauma history is rare. Herein, we present a patient with cryptogenic temporal hollowing. A 22-year-old man without any history of craniofacial interventions or trauma presented with temporal hallowing. Magnetic resonance imaging revealed fatty degeneration of the left temporalis muscle. Electromyography and nerve conduction study showed no signs of neurologic abnormalities. The patient received autologous fat injection of 30 mL harvested from the left thigh using the modified Coleman technique. Temporal hollowing is commonly caused by atrophy of the superficial temporal fat pad. Its incidence is reported to be as high as 6% after coronal approach operation. Augmentation using porous hydroxyapatite or titanium mesh is a treatment option. Autologous fat graft can also be an option for mild to moderate temporal hollowing. In this case, a patient with no history of trauma, surgery, or myogenic disease developed temporal hollowing. Further study of the little-known cryptogenic form of temporal hollowing is warranted.

• Journal of International Society for Simulation Surgery
• /
• 제3권2호
• /
• pp.77-79
• /
• 2016

Osteoma is one of the benign tumor that occurs on the bones all over the body. Mostly the simple excision is known to be enough. However, sometimes we encounter the troublesome situation where the osteoma is located in very challenging area, which results in the recurrence. 26 year female presented with the intractable intracranial osteoma. Given the disease entity of the osteoma, the simple excision would be enough or conservative management. But this osteoma turned out to be huge and recurrent in spite of the endoscopic resections, which causes the facial disappearance accompanied by the orbital vertical dystopia. Moreover, the patient's main concern was the pain. We performed the intracranial resection of the whole lesion and reconstructed the skull base and frontal bone as well as the part of the orbital wall. In order to restore the original bony anatomy, the 3D printing model was used based on the titanium mesh. I report this unusual case of the intractable intracranial huge osteoma. This report may be helpful for the other surgeons to make a decision on their similar cases in the future.

• 한국환경과학회지
• /
• 제18권1호
• /
• pp.49-60
• /
• 2009

Fabrication and oxidants formation of 1 and 2 component metal oxide electrode, which is known to be so effective to destruct non-biodegradable organics in wastewater, were studied. Five electrode materials (Ru, Pt, Sn, Sb and Gd) were used for the 1 and 2 component electrode. The metal oxide electrode was prepared by coating the electrode material on the surface of the titanium mesh and then thermal oxidation at $500^{\circ}C$ for 1 h. The removed RhB per 2 min and unit W for one component electrode decreased in the following sequences: Ru/Ti>Sb/Ti>Pt/Ti>Gd/Ti>Sn/Ti. The concentration of oxidants generated in 1 and 2 component electrodes was in the order of: $ClO_2$> free Cl>$H_2O_2>O_3$. OH radical was not generated from in entire one and two component electrodes. RhB degradation rate and generated oxidants of the Ru-Sn=9:1 electrode was higher than that of the two component electrode. The exact relationship between the removal of RhB and the generated oxidants concentration was not obvious. However, it was assumed that electrode with high RhB decolorization had high oxidant concentration.

• 한국표면공학회지
• /
• 제42권1호
• /
• pp.53-57
• /
• 2009

Recovery of heavy-metallic component from a waste solution of factory was undertaken by the solar cell electricity. The solution was obtained from an electrolytic etching process of 316L stainless steel. The electrolysis of the solution for recovery of heavy metallic components was made with platinum plated titanium mesh anode and copper plate cathode. Analysis for the solution and electro-winned materials were made by EDS, XRD and SEM. Iron, chromium, and sulfur components were recovered on the cathode from the solution. Result of EDS analysis for the electro-winned materials revealed that some metal oxide were contained in the recovered material. The recovered materials were expected to have metallic form only by the electrolysis, but metal compounds were contained because of weak solar cell power. Nickel and manganese component in the solution doesn't recovered by this electrolysis process, but they made a sludge with phosphoric acid in the solution.

• 대한두개안면성형외과학회지
• /
• 제15권3호
• /
• pp.129-132
• /
• 2014

Facial skeletal remodeling was revolutionized more than 30 years ago, by the work of Tessier and other craniofacial surgeons. However, the need to correct the skeleton in the upper third of the face is not frequently diagnosed or treated in aesthetic facial surgery. Here, we report on the aesthetic correction of a protrusive forehead. A patient visited our hospital for aesthetic contouring with a prominent forehead. The anterior wall of the frontal sinus was removed with a craniotome via the bicoronal approach. After the excised bone was repositioned, it was fixed with a titanium mesh plate and screws. An electric burr was used to contour the supraorbital rim and frontal bone. Once the desired shape was achieved, the periosteum was replaced, and the wound was closed in layers. When performed properly, frontal sinus contouring could significantly improve the appearance in patients with a prominent forehead. Plastic surgeons must carefully evaluate patients with a prominent forehead for skeletal remodeling that involves the accurate and safe repositioning of the anterior wall of the frontal sinus.