• The Journal of Korean Academy of Prosthodontics
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• v.31 no.4
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• pp.580-610
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• 1993

The purpose of this study was to analyse the deflection and stress distribution at the supporting bone and it's superstructure by the alteration of angulation between implant and it's implant abutment. For this study, the free-end saddle case of mandibular first and second molar missing would be planned to restore with fixed prosthesis. So the mandibular second premolar was prepared for abutment, and the cylinder type osseointegrated implant was placed at the site of mandibular second molar for abutment. The finite element stress analysis was applied for this study. 13 two-dimensional FEM models were created, a standard model at $0^{\circ}$ and 12 models created by changing the angulation between implant and implant abutment as increasing the angulation mesially and distally with $5^{\circ}$ unittill $30^{\circ}$. The preprocessing decording, solving and postprocessing procedures were done by using FEM analysis software PATRAN and SUN-SPARC2GX. The deflections and von Mises stresses were calculated under concentrated load (load 1) and distributed load(load 2) at the reference points. The results were as follows : 1. Observing at standard model, the amount of total deflection at the distobuccal cusp-tip of pontic under concentrated load was largest of all, and that at the apex of implant was least of all, and the amount of total deflection at the buccal cusp-tip of second premolar under distributed load was largest of all, and that at the apex of implant was least of all. 2. Increasing the angulation mesially or distally, the amounts of total deflection were increased or decreased according to the reference points. But the order according to the amount of total deflection was not changed except apex of second premolar and central fossa of implant abutment under concentrated load during distal inclination. 3. Observing at standard model, the von Mises stress at the distal joint of pontic under concentrated load was largest of all, and that at the apex of implant was least of all. The von Mises stress at the distal margin of second premolar under distributed load was largest of all, and that at the apex of Implant was least of ail. 4. Increasing the angulation of implant mesially, the von Mises stresses at the mesial crest of implant were increased under concentrated load and distributed load, but those were increased remarkably under distributed load and so that at $30^{\circ}$ mesial inclination was largest of all. 5. Increasing the angulation of implant distally, the von Mises stresses at the distal crest of implant were increased remarkably under concentrated load and distributed load, and so those at $30^{\circ}$ distal inclination were largest of all.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.140-145
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• 2008

After limb salvage operation becomes popular, reconstruction method of epi-metaphyseal osteosarcoma is relatively standardized though it may be operator's matter of preference. Most limb salvage techniques presently used are prosthesis reconstruction and osteoarticular allograft. In the case of prosthesis, it is very stable and shows good postoperative functional score, however, finally, it has a weak point of requirement for removal procedure due to failure. In the long run, allograft reconstruction has a good merit. But, it has a weak point of difficulties in securing the demanded size and shape. Allograft reconstruction should be performed only in the case of safe margin and established indication. In limb salvage operation, intercalary reconstruction is useful method in diaphyseal osteosarcoma, however, in metaphyseal osteosarcoma, the indication is not confirmed. We treated 17 year old osteosarcoma patient with localized in the tibial medial condyle with proximal medial condylectomy and pasteurized bone reconstruction in the conviction of safe surgical margin. We report this case because we guess if this procedure may be applied to premature patients, despite failure hemiarthroplasty can be tried successfully.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.33-43
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• 2023

Pathological wear across the entire dentition causes problems such as collapsed occlusal plane, reduced vertical dimension, anterior premature contact, inadequate anterior guidance, and tooth migration, thereby induce symptoms such as temporomandibular joint disorder, reduced masticatory efficiency, and tooth hypersensitivity. For the treatment of patients with excessive wear, evaluation of vertical dimension should be preceded along with analysis of the cause. The patient in this case was a 45-year-old female with a history of orthognathic surgery. Through clinical examination, radiographic examination, and model analysis, overall tooth wear, interdental spacing in the anterior maxillary region, retruded condylar position, and insufficient interocclusal space for prosthetic restoration were confirmed. Full mouth rehabilitation with increased vertical dimension was planned, the patient's adaptation to the new vertical dimension was evaluated with a removable occlusal splint and temporary prosthesis, and cross-mounting was performed based on the temporary restoration to fabricate the definitive zirconia prosthesis, maintaining the adjusted vertical dimension. It showed satisfactory functional and esthetic results through stable restoration of the occlusal relationship.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.113-122
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• 2024

The gradual teeth wear with age is a natural phenomenon, but excessive wear beyond physiological levels can lead to vertical dimension loss, occlusal imbalance, temporomandibular joint disorders, and periodontal disease. In such cases, prosthodontic restoration becomes necessary emphasizing the importance of appropriate vertical dimension increase and stable occlusion in central relation (CR). In this case, a 74-year-old patient with clenching and grinding habit had severe teeth wear and after assessing interocclusal distance, wear degree, pronunciation, and facial profile, it was decided to perform full-mouth fixed prosthesis restoration with a 4 mm vertical dimension increase. And the significantly displaced Maximum Intercuspal Position (MICP) caused by parafunctional movements was re-established as a stable mutually protective occlusal relationship at centric relation and after a successful 4 months adaptation to provisional restorations, the final prosthesis was fabricated. During 4months of observation periods, stable occlusion in central relation and mutual protection occlusal relationships were maintained and the patient was satisfied with function and aesthetics, leading to this report.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.3
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• pp.145-154
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• 2001

In the past, many dentist were interested mainly in the mechanical aspects such as tooth preparation and retainer types for making dental restoration. But, these days, the concept of restorative treatment emphasizes the importarce of gnatic system and masticatory muscles in addition to oral cavity. So, the current considerations for the fixed prosthodontic treatment include the stabilization of temporomandibular joint and neuromuscualr system and the relationship of periodontal ligament and occlusion. To achieve the above objectives, occlusal splint has been used as one of the mouth preparations for restorative treatment. The objectives of occlusal splint are as follows; 1. To use as preliminary application for periodontal-occlusal treatment 2. To provide proper vertical dimension 3. To control abnormal habits and parafunction 4. To treat the temporomandibular disease and myofascial pain 5. To establish the new therapeutic position In some cases, the patients had improper vertical dimension and occlusal interferences caused by prostheses reconstucted using centric relation recorded without considering the health of TMJ and manticatory muscle. And these prosthesis act as primary source that cause pathologic phenomenon in periodontal ligament, muscles and TMJ. Physiologically, in order to make the treatment occlusion guided by proper centric relation method, the method should be guided after the use of occlusal splint for some period. The main objective of prosthetic treatment is to maintain the function and health of stomatognathic system. So, one of the most important things that have to be performed by clinicians is a clinical ability to do the correct diagnosis and treatment planning based on the stomatognatic function and occlusion.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.729-736
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• 2008

Purpose: Anterior ridge defect after tooth extraction results in unfavorable appearance. Ridge augmentation procedures should be preceded by careful surgical-prosthetic treatment planning, and various techniques can be used in anterior ridge augmentation. Materials and Methods: Three patients showed deformed ridges after tooth extraction. Three different techniques ; onlay-interpositional connective tissue graft; bovine hydroxyapatite graft with free connective tissue graft; bovine hydroxyapatite graft with resorbable collagen membrane following free connective tissue graft; were used for anterior ridge augmentation. Result: Soft tissue graft can be used in small amount of ridge defect, hard tissue graft combined with soft tissue graft can be used in large amount of ridge defect. After ridge augmentation, about three months of healing period, augmented tissue was stabilized. The final restoration was initiated after this healing period, and the tissue form was maintained stable. Conclusion: Careful diagnosis and surgical-prosthetic treatment planning with joint consultation prior to surgery should be performed in order to attain an optimal esthetic results.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.1
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• pp.10-16
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• 2008

With the advent of effective chemotherapy and the realization of high economic cost associated with amputation, limb salvage surgery has become the standard of treatment in children with primary malignant bone tumors. Reconstruction after resection of malignant bone tumors of children has to address the leg length inequality and also has to be durable to cope with high functional demands of young patients. Expandable endoprostheses have been used in children for achieving limb length equality with substantial risk of complications. Recently, significant advances in prosthetic designs have reduced the morbidities associated with these prostheses. The purpose of this study was to review the indications, characteristics, complications and recent developments of expandable endoprostheses used for malignant bone tumors in children.

• Clinics in Shoulder and Elbow
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• v.23 no.1
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• pp.20-26
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• 2020

Background: High complication rate after open reduction and internal fixation can lead to use of primary total elbow replacement (TER) in treatment of complex distal humerus fractures in elderly patients. The purpose of this study was to investigate the short-term outcomes and complications after primary TER in patients with complex distal humerus fracture. Methods: Nine patients with acute complex distal humerus fracture were treated by primary TER using the semiconstrained Coonrad-Morrey prosthesis. The mean age of patients was 72.7 years (range, 63-85 years). Clinical and radiographic outcomes were evaluated over a mean follow-up of 29.0 months (range, 12-65 months) using visual analog scale (VAS) score for pain; Mayo elbow performance score (MEPS); Quick Disabilities of the Arm, Shoulder, and Hand (Quick-DASH) score; and serial plain radiographs. Complications were also evaluated. Results: At the final follow-up, mean VAS, MEPS, and Quick-DASH scores were 1.2, 80.5, and 20, respectively. The mean range of motion was 127.7° of flexion, 13.8° of extension, 73.3° of pronation, and 74.4° of supination. There was no evidence of bushing wear or high-grade implant loosening on serial plain radiographs. Three complications (33.3%) comprising two periprosthetic fractures and one ulnar neuropathy were observed. Conclusions: Primary TER for treatment of complex distal humerus fractures in elderly patients yielded satisfactory short-term outcomes. However, surgeons should consider the high complication rate after primary TER.

• Journal of Veterinary Clinics
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• v.34 no.6
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• pp.454-458
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• 2017

A Maltese (case 1) and a Pomeranian (case 2) presented with acute right and left hind limb weight-bearing lameness. On physical examination, they exhibited severe pain and crepitus on the coxofemoral joint of affected hind limb. In addition, decreased thigh girth measurements were noted compared with the opposite leg. Radiological exam revealed necrotic areas in the femoral head of affected hind limb. These dogs were diagnosed with Legg-$Calv{\acute{e}}$-Perthes disease (LCPD). The dogs underwent micro total hip replacement (THR). After surgery, at 3 years (case 1) and 7 months (case 2), both dogs recovered normal activity. The thigh girth and lameness scores were apparently improved in the affected limbs of both dogs. No complications of prosthesis implants, such as loosening, were noted. The clinical outcomes of these cases indicate that dogs with LCPD can be successfully treated with micro THR and have a good prognosis immediately after surgery.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.1
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• pp.32-37
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• 2002

High grade surface osteosarcoma is the most rare subtype of osteosarcoma arising on the surface of bone, accounting for less than 1% of the total number of osteosarcomas. Only a few case reports and studies have been reported in the world. In Korea, only one case out of 127 osteosarcomas has been described up to now, but there was no information about the patient, clinicopathologic features and treatment. We experienced a case of high grade surface osteosarcoma in the subtrochanteric area of a 66-year-old female and treated her with neoadjuvant chemotheraphy, wide resection and limb salvage operation with tumor prosthesis and adjuvant chemotheraphy. This tumor is identical to conventional high grade intramedullary osteosarcoma in histology, treatment and prognosis. So, this tumor should be differentiated from other surface osteosarcomas such as parosteal osteosarcoma and periosteal osteosarcoma.