• Archives of Craniofacial Surgery
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• v.10 no.1
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• pp.23-28
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• 2009

Purpose: Blow out fracture can present tenderness, swelling, enophthalmos, extraoccular muscle limitation, paresthesia, diplopia according to severity of injury, so reconstruction of blow out fracture is important. Orbital soft tissue should be in orbit and defected orbital wall should be corrected by autologus tissue or alloplastic implants. Every implants have their merits and faults, every implants are used various. This study was designed to compare the sequelae of blow-out fracture repair using the alloplastic implants: micro-titanium mesh(Micro Dynamic titanium $mesh^{(R)}$, Leibinger, Germany), porous polyethylene ($Medpor^{(R)}$, Porex, USA), absorbable mesh plate(Biosorb $FX^{(R)}$ . Bionx Implants Ltd, Finland). Methods: Between January 2006 and April 2008, 52 patients were included in a retrospective study analysing the outcome of corrected inferior orbital wall fracture with various kind of implants. Implants were inserted through subciliary incision. Twenty patients were operated with micro-titanium mesh, fourteen patients with porous polyethylene and eighteen patients with absorbable mesh plate. In comparative category, enophthalmos, diplopia, range of motion of extraoccular muscle, inferior orbital nerve injury were more on frequently statistically in patients. Results: Fourteen of 18 patients underwent surgical repair to improve diplopia, 11 of 17 patients to improve parasthesia, 11 of 15 patients to improve enophthalmos, 8 of 9 patients to improve extraoccular muscle limitation. Duration of follow-up time ranged from 6 months to 12 months(mean, 7.4 months). There was no statistic difference of sequelae between micro titanium mesh and porous polyethylene and absorbable mesh plate in blowout fracture, inferior wall. Conclusion: There is no difference of sequelae between micro-titanium mesh, porous polyethylene and absorbable mesh plate in blow-out fracture, inferior wall. The other factors such as defect size, location, surgeon's technique, may influence the outcome of blow-out fracture repair.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.613-618
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• 2010

Purpose: The coronal approach for repair of frontal sinus fractures is associated with significant adverse sequelae including a long scar, alopecia, paresthesias, and, uncommonly, facial nerve injury. To minimize these complications, an endoscopic approach for repair of frontal sinus fractures was developed. The authors now present the results of an endoscopy-assisted approach for the treatment of frontal sinus fractures. Methods: From 2002 to 2009, five patients with frontal sinus fracture underwent endoscopic repair. Two slit incisions were placed in the scalp, and one or two stab incisions directly over the fractures were placed in the forehead. After subperiosteal dissection, fracture segments were reduced under direct vision and fixed with microplates or fibrin glue. Results: All patients had good cosmetic results and remained free of sinus complaints. There were no perioperative complications reported. Conclusion: Endoscopic repair of frontal sinus fractures is an efficacious technique that significantly reduces patient morbidity. A relatively wide range of anterior table fractures can be reduced using an endoscope. In cases of complicated comminuted fractures, fibrin glue helps to achieve satisfactory endoscopic reduction. Endoscopic repair is an alternative treatment for various anterior table fractures of the frontal sinus.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.149-157
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• 2005

Statement of problem. Dental ceramics exhibit excellent esthetic property, compressive strength, chemical durability biocompatibility and translucency. However, it suffers from inherent brittle fractures. Various techniques and materials for intraoral porcelain repair has been suggested. Purpose. This study is to compare the tensile bond strength of four commonly used porcelain repair systems (Vivadent, Bisco, Ulttadent, Voco) and to insure the best system for the clinical application to the fractured porcelain. Materials and methods. A total of fifty specimens were fabricated. Specimens were stored in $37^{\circ}C$ distilled water for 7 days and thermocycling was performed(1000 cycles), and subjected to a tensile force parallel to the repair resin and porcelain interface by use of an Universal Testing Machine. Result. 1. Voco showed the highest tensile bond strength. In decreasing order, the tensile bond strength of the other materials was as follows : Ultradent, Bisco, Vivadent. 2. There was a statistically significant difference between the porcelain repair systems(Voco, Ultradent > Bisco, Yivadent) (p<0.05). 3. SEM examination of prepared porcelain surfaces revealed that the surface treated with Voco showed brittle fracture. However, Ultradent, Bisco and Vivadent showed ductile fracture. 4. All specimens treated with four porcelain repair systems showed adhesive failure between porcelain and composite resin.

• Structural Engineering and Mechanics
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• v.50 no.4
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• pp.525-539
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• 2014

Bonded composite-patch repair has been widely used to restore or extend the service life of damaged structures due to its effectiveness as a mechanical repair technique. In this paper using extended finite element method (XFEM), three-dimensional crack models are developed to examine the fracture behavior of centrally cracked aluminum plates repaired with single and double sided composite patches. Stress intensity factor (SIF) at the crack tip is used as the fracture criterion. In this regard, the effects of the crack lengths, patch materials, orientation of plies, adhesive and patch thickness are examined to estimate the SIF of the repaired plate and the repair performance. The obtained results show that composite patches have significant effect on reduction of the SIF at the crack tip. It is also proved that using double symmetric repair, in comparison to single one, reduces considerably SIF at the crack tip. Hence, the residual strength can be improved significantly as well as fatigue life of the structure. Investigation of ply orientation effects shows SIF increase as the ply orientation is changed from $0^{\circ}$ (perpendicular to the advancing crack) to $90^{\circ}$ (parallel to the crack line). However, the effectiveness of the ply orientation depends on the loading direction and the crack direction.

• Journal of Veterinary Science
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• v.21 no.6
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• pp.90.1-90.11
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• 2020

Background: Mandibular fractures are common in camels, leading to considerable economic losses. This study explored methods of improving mandibular fractures repair, adjuvant with interdental wire, or bone plate fixation. Autologous bone marrow (BM) injection enhances osteogenesis and rapid healing. Objectives: To investigate the effect of autologous BM aspirate as an adjuvant treatment for repairing mandibular fractures in camels with interdental wire, or bone plate fixation. Methods: Thirty dromedary camels aged 5-8 years and of both sexes were randomly divided into 4 treatment groups: group 1 (n = 10) treated with stainless steel wire fixation and BM injection at the fracture line, group 2 (n = 10) treated with plate fixation and BM injection at the fracture line, group 3 (n = 5) treated with stainless steel bone wire fixation and placebo saline injection at the fracture line, and group 4 (n = 5) treated with plate fixation and placebo injection at the fracture line. The mandibular fractures were followed weekly for 12 weeks postoperatively to assess improvement and healing based on clinical evaluation, radiographic union scale, and bone turnover markers (i.e., bone alkaline phosphatase, osteocalcin, pyridinoline, and deoxypyridinoline). Results: Compared to other groups, elevated bone turnover markers in group 1 were demonstrated (p < 0.05) on the seventh postoperative day. Likewise, compared to other groups, both clinical findings and radiographic union scale significantly improved (p < 0.05) in group 1 on the 56th postoperative day. Conclusions: BM aspirate has a promising beneficial osteogenic effect on mandibular fracture repair in camels, most notably when combined with interdental wire fixation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.3
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• pp.42-50
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• 2020

This study explores the effects of repair width on the deposition characteristics and mechanical properties of stainless steel samples repaired using direct energy deposition (DED). In the DED repair process, defects such as pores and cracks can occur at the interface between the substrate and deposited material. In this study, we changed the width of the pre-machined zone for repair in order to prevent cracks from occurring at the inclined surface. As a result of the experiment, cracks of 10-40 ㎛ in length were formed along the inclined slope regardless of the repair width. Yield and tensile strength decreased slightly as the repair width increased, but the total and uniform elongation increased. This is due to the orientation of the crack. For specimens with a repair width of 20 mm, yield and tensile strength were 883 MPa and 1135 MPa, respectively. Total and uniform elongations were 14.3% and 8.2%, respectively. During observation of the fracture specimens, we noted that the fracture of the specimen with an 8 mm repair width occurred along the slope, whereas specimens with 14 mm and 20 mm repair depths fractured at the middle of the repaired region. In conclusion, we found that tensile properties were dependent upon the repair width and the inclination of the crack occurred at the interface.

• The Journal of Advanced Prosthodontics
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• v.11 no.2
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• pp.95-104
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• 2019

PURPOSE. To evaluate the effect of surface treatments and repair materials on the shear bond strength and to measure the fracture toughness of CAD/CAM provisional restoration materials. MATERIALS AND METHODS. Four CAD/CAM (3D printing: Nextdent C&B and ZMD-1000B Temporary, CAD/CAM resin block: Yamahachi PMMA disk and Huge PMMA block) and four conventional (monometacrylate: Jet and Alike, dimetacrylate: Luxatemp and Protemp 4) materials were selected to fabricate disk-shaped specimens and divided into six groups according to surface treatment (n=10). CAD/CAM materials were repaired with Jet or Luxatemp, while conventional materials were repaired with their own materials. The shear bond strength was measured by using universal testing machine. Ten rectangular column-shaped specimens for each material were fabricated to measure the fracture toughness by single edge v notched beam technique. Statistical analysis was performed by one-way ANOVA. RESULTS. The highest shear bond strength of CAD/CAM materials was achieved by SiC paper + sandblasting. It was also accomplished when repairing 3D printing materials with Luxatemp, and repairing CAD/CAM resin blocks with Jet. Yamahachi PMMA disk showed the highest fracture toughness. Nextdent C&B showed the lowest fracture toughness value but no statistically significant difference from Alike and Luxatemp (P>.05). CONCLUSION. In order to successfully repair the CAD/CAM provisional restoration, mechanical surface treatment and appropriate repair material according to the CAD/CAM material type should be selected. The CAD/CAM provisional materials have proper mechanical properties for clinical use as compared to conventional materials.

• Journal of Korean Foot and Ankle Society
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• v.15 no.1
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• pp.13-17
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• 2011

Purpose: To evaluate the clinical results of anteroinferior tibiofibular ligament avulsion fracture accompanied ankle fractures treated with anatomical reduction and internal fixation. Materials and Methods: From January 2007 to April 2010, 30 cases with anteroinferior tibiofibular ligament avulsion fracture that treated with anatomical reduction and internal fixation were analyzed. The average follow-up period was 26 months (minimum 6 months). We have reviewed the bony union, complication and subjective satisfaction according to the fracture classification and method of internal fixation. Results: Among 30 cases, 28 cases were occurred in Lauge-Hansen classification supination-external rotation type, one case was fracture-dislocation and one case was Maisonneuve fracture. We have performed internal fixation with Mini screw in 11 cases, K-wire in 10 cases, repair in six cases and Mini screw & K-wire in three cases. In all cases bony union was completed. two cases in Mini screw, one case in K-wire, two cases in repair and one case in Mini screw & K-wire revealed LOM of ankle joint. Skin irritation and superficial peroneal nerve irritation happened in one case each. Other cases show good subjective satisfaction. Conclusion: Anteroinferior tibiofibular ligament avulsion fracture accompanied with ankle fracture is a good clinical outcome with internal fixation. So we should not miss out the anteroinferior tibiofibular ligament avulsion fracture in radiologic evaluation or operation room.

• Journal of Mechanical Science and Technology
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• v.16 no.5
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• pp.599-608
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• 2002

Finite element analysis for the stress intensity factor (SIF) at the skin/stiffener structure with inclined central crack repaired by composite stiffened panels is developed. A numerical investigation was conducted to characterize the fracture behavior and crack growth behavior at the inclined crack. In order to investigate the crack growth direction, maximum tangential stress (MTS) criterion are used. Also, this paper is to study the performance of the effective bonded composite patch repair of a plate containing an inclined central through-crack. The main objective of this research is the validation of the inclined crack patching design. In this paper, the reduction of stress intensity factors at the crack-tip and prediction of crack growth direction are determined to evaluate the effects of various non-dimensional design parameter including; composite patch thickness and stiffener distance. We report the results of finite element analysis on the stiffener locations and crack slant angles and discuss them in this paper. The research on cracked structure subjected to mixed mode loading is accomplished and concludes that more work using a different approaches is necessary. The authors hope the present study will aid those who are responsible for the repair of damaged aircraft structures and also provide general repair guidelines.

• International Journal of Concrete Structures and Materials
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• v.2 no.1
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• pp.3-8
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• 2008

Polymer-cement composites are known repair materials. The aim of this work is to investigate the influence of various amount of dispersion of carboxylated styrene-butadience copolymer on the selected mechanical properties of polymer-cement concrete (PCC) and on its adhesion to ordinary concrete. The compressive, flexural and tensile strengths as well as frost resistance and fracture resistance of the composites are tested. Adhesion strength of PCC to ordinary concrete, as one of most important performance of good repair material is evaluated and analyzed using three test methods. The results obtained in standard pull-off test are compared with the two other tests. The first one, which is an adaptation of WST (wedge splitting test) characterizes crack propagation in the plane of bond created during repair. In the second test the resistance to shear is a measure of adhesion strength.