• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.505-510
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• 2002

The attenuation of waves transmitted through non-conservative joints that are shown in many paractical structures, is affected by the impedance and the orientation of the joint. In this paper, the joints between plate structures are assumed to be modeled as linear spring-dashpot systems and the transmission and reflection of vibration energy in the medium to high frequency ranges are investigated. The calculated power transmission and reflection coefficients are applied to the PFA method for the prediction of energy density and intensity in structures.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.353.2-353
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• 2002

The attenuation of waves transmitted through non-conservative joints that are shown in many practical structures, is affected by the impedance and the orientation of the joint. In this paper, the joints between plate structures are assumed to be modeled as linear spring-dashpot systems and the transmission and reflection of vibration energy in the medium to high frequency ranges are investigated. (omitted)

• Clinics in Shoulder and Elbow
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• v.21 no.1
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• pp.48-55
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• 2018

While non-operative treatment with structured rehabilitation tends to be the strategy of choice in the management of Rockwood type III acromioclavicular joint injury, some advocate surgical treatment to prevent persistent pain, disability, and prominence of the distal clavicle. There is no clear consensus regarding when the surgical treatment should be indicated, and successful clinical outcomes have been reported for non-operative treatment in more than 80% of type III acromioclavicular joint injuries. Furthermore, there is no gold standard procedure for operative treatment of type III acromioclavicular joint injury, and more than 60 different procedures have been used for this purpose in clinical practice. Among these surgical techniques, recently introduced arthroscopic-assisted procedures involving a coracoclavicular suspension device are minimally invasive and have been shown to achieve successful coracoclavicular reconstruction in 80% of patients with failed conservative treatment. Taken together, currently available data indicate that successful treatment can be expected with initial conservative treatment in more than 96% of type III acromioclavicular injuries, whereas minimally invasive surgical treatments can be considered for unstable type IIIB injuries, especially in young and active patients. Further studies are needed to clarify the optimal treatment approach in patients with higher functional needs, especially in high-level athletes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.2
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• pp.43-51
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• 2018

Temporomandibular disorders (TMDs) are diseases that affect the temporomandibular joint and supporting structures. The goal of treatment for TMDs is elimination or reduction of pain and return to normal temporomandibular joint function. Initial treatment for TMDs is non-invasive and conservative, not surgical. Oral and maxillofacial surgeons should fully understand and actively care about non-invasive treatments for TMDs. The purpose of this study is to review the validity and outcomes of non-invasive and surgical treatment modalities for TMDs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.3
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• pp.111-116
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• 2014

Objectives: Dislocation of the temporomandibular joint may occur for various reasons. Although different invasive methods have been advocated for its treatment, this study highlights the value of non-invasive treatment options even in chronic cases in a resource-poor environment. Materials and Methods: A seven-year retrospective analysis of all patients managed for temporomandibular joint dislocation in our department was undertaken. Patient demographics, risk factors associated with temporomandibular joint dislocation and treatment modalities were retrieved from patient records. Results: In all, 26 patients were managed over a seven-year period. Males accounted for 62% of the patients, and yawning was the most frequent etiological factor. Conservative treatment methods were used successfully in 86.4% of the patients managed. Two (66.7%) of the three patients who needed surgical treatment developed complications, while only one (5.3%) patient who was managed conservatively developed complications. Conclusion: Temporomandibular joint dislocation appears to be associated with male sex, middle age, yawning, and low socio-economic status, although these observed relationships were not statistically significant. Non-invasive methods remain an effective treatment option in this environment in view of the low socio-economic status of the patients affected.

• Journal of Korean Foot and Ankle Society
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• v.5 no.1
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• pp.35-42
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• 2001

Purpose: To analyze the results of conservative or surgical treatment after computed tomograhy(CT) classification in intraarticular calcaneal fractures. Materials and methods: From January 1996 to May 1999, we prospectively analyze 23 cases of intraarticular calcaneal fractures who were treated conservatively or operated by open reduction and internal fixation by extensive L-shaped lateral approach after CT classification. Results: A functional scoring system of 0-100 points which was based upon the responses to AOFAS Ankle-Hindfoot Scale for the operative group was at 82.8, compared with 73.2 for the non-operative group, and these were meaningful statistically(P<0.05). Of type I fracture, in the operative group there were 2 excellent results and in the non-operative group there were 2 excellent results, 1 good result. or type II fractures, in the operative group there were 2 excellent results, 3 good results, 1 fair result and in the non-operative group there were 1 good result, 1 fair result, 2 poor results. Of type III fractures, in the operative group there were 2 fair results, 2 poor results and in the non-operative group there were 1 fair result, 3 poor results. Bohler angles of subtalar joint were changed from initial average $13.3^{\circ}$ to postoperative average $20.9^{\circ}$ for the operative group compared with from initial average $15.5^{\circ}$ to follow-up average $14.8^{\circ}$ of the non-operative group(P<0.01). Conclusions: Computed tomography in the evaluation of intraarticular calcaneal fractures is effective tool. We believed that open reduction and internal fixation in all Crosby & Fitzgibbons type II and according to degrees of comminution reducible type III for the intraarticular calcaneal fractures is more effective method than conservative treatment.

• Earthquakes and Structures
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• v.11 no.5
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• pp.905-924
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• 2016

Several two-dimensional analytical beam column joint models with varying complexities have been proposed in quantifying joint flexibility during seismic vulnerability assessment of non-ductile reinforced concrete (RC) frames. Notable models are the single component rotational spring element and the super element joint model that can effectively capture the governing inelastic mechanisms under severe ground motions. Even though both models have been extensively calibrated and verified using quasi-static test of joint sub-assemblages, a comparative study of the inelastic seismic responses under nonlinear time history analysis (NTHA) of RC frames has not been thoroughly evaluated. This study employs three hypothetical case study RC frames subjected to increasing ground motion intensities to study their inherent variations. Results indicate that the super element joint model overestimates the transient drift ratio at the first story and becomes highly un-conservative by under-predicting the drift ratios at the roof level when compared to the single-component model and the conventional rigid joint assumption. In addition, between these story levels, a decline in the drift ratios is observed as the story level increased. However, from this limited study, there is no consistent evidence to suggest that care should be taken in selecting either a single or multi component joint model for seismic risk assessment of buildings when a global demand measure such as maximum inter-storey drift is employed in the seismic assessment framework.

• Journal of Oral Medicine and Pain
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• v.22 no.1
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• pp.7-13
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• 1997

In order to evaluate the outcome of conservative treatment for acute or chronic closed lock, 127 patients were subjected at the Dept. of Oral Medicine, PNUH, from 1991. All the symptoms were analyzed and the results according to treatment modalities were compared before and after treatment. 1. Closed lock patients were more often seen in women of twenty and thirty. 2. The most common reasons for treatment were functional pain, limitation of mouth opening, restricted laterotrusion to non-effected side, deflection on opening but, on the contrary, noise was the least. 3. Most of closed lock patients were curedin six months. 4. Conservative treatment including stabilization splint produced better results. 5. Functional pain and limitation of mouth opening were relieved and maximumm comfortable opening was expanded, but joint noise decreased in the chronic and increased in the acute.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.448-456
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• 2011

Introduction: Condylar fractures are common in the maxillofacial region, comprising 29-40 percent of all mandibular fractures, accounting for about 20-62 percent). Previous studies reported that pediatric condylar fractures can cause disorders in facial growth and function, and the treatment methods have been controversial. Recently, conservative treatment has shown good results in skeletal growth and functional recovery but the conservative treatment of pediatric condylar fractures has shown unpredictable and undesirable results in some cases, such as facial asymmetry and temporomandibular joint disorder. This study examined the specific age groups and specific mandibular condylar fracture type in growing children treated conservatively in the past. Materials and Methods: Eighteen patients (10 men and 8 women) who received conservative treatment for unilateral condylar fractures in Dankook University Dental Hospital between 2000 to 2007 were followed up for a mean period of 7.2 years. Results: In the survey of 18 pediatric patients who received conservative treatment for condylar fractures, the incidence of temporomandibular dysfunction and growth disturbance was 45% and 35%, respectively. Conclusion: In all complications, the symptoms observed most frequently was mouth opening displacement of the mandible exceeding 2 mm. The other complications of functional and growth disturbance included facial asymmetry concentrated along specific condylar types. Complications including facial asymmetry and functional and growth disturbances showed an increasing tendency according to the specific fracture types. Functional and growth disturbances in the undisplaced condylar fracture type showed a lower incidence(P <0.05). Functional and growth disturbances differed according to the fracture type, which has poor relationship with articular fossa and condyle(P <0.05). Functional and growth disturbance in the cases of the high-level condylar fracture type showed a higher incidence(P <0.05). The functional and growth disturbances of the fracture types were similar in the fragment-contact and non-contact groups(P >0.05).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.5
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• pp.305-309
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• 2012

Temporomandibular joint (TMJ) subluxation and dislocation are uncommon but very unpleasant and distressing conditions to patients. Subluxation of the TMJ is an excessively abnormal condylar excursion secondary to flaccidity and laxity of the capsule. When the condyle head excurses anterior to the eminence upon wide opening, it can return to the fossa by self-manipulation or non-surgical conservative reduction. Surgery is recommended if a complete dislocation, so-called open lock, occurs as a chronic or recurrent protracted condition that cannot be reduced voluntarily. A range of surgical procedures can be performed to limit condylar hypermobility inclusing soft tissue tethering, creation of articular obstacles, removal of mechanical blockade and augmentation of articular eminence using different kinds of grafts. In the present case, a 74-year-old woman was diagnosed with a chronic TMJ dislocation that had lasted for 6 months. Bilateral condylectomy was performed and the post-operative results were good without functional limitations or recurrence.