• Journal of the Korean Academy of Esthetic Dentistry
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• v.30 no.2
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• pp.71-90
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• 2021

The virtual patient dataset is a collection of diagnostic data from various sources acquired from a single patient into a coordinate system of three-dimensional visualization. Virtual patient dataset makes it possible to establish a treatment plan, simulate various treatment procedures, and create a treatment planning delivery device. Clinicians can design and simulate a patient's smile on the virtual patient dataset and select the optimal result from the diagnostic process. The selected treatment plan can be delivered identically to the patient using manufacturing techniques such as 3D printing, milling, and injection molding. The delivery of this treatment plan can be linked to the final prosthesis through mockup confirmation through provisional restoration fabrication and delivery in the patient's mouth. In this way, if the diagnostic data superimposition and processing accuracy during the manufacturing process are guaranteed, 3D digital smile design simulated in 3D visualization can be accurately delivered to the real patient. As a clinical application method of the virtual patient dataset, we suggest a decision-making method that can exclude occlusal adjustment treatment from the treatment plan through the digital occlusal pressure analysis. A comparative analysis of whole-body scans before and after temporomandibular joint treatment was suggested for adolescent idiopathic scoliosis patients with temporomandibular joint disease. Occlusal plane and smile aesthetic analysis based on the virtual patient dataset was presented when treating patients with complete dentures.

• Journal of Korean Dental Science
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• v.16 no.2
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• pp.128-148
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• 2023

Dementia is an umbrella term that describes the loss of thinking, memory, attention, logical reasoning, and other mental abilities to the extent that it interferes with the activities of daily living. More than 50 million individuals worldwide live with dementia, which is expected to increase to 131 million by 2050. Recent research has shown that poor oral health increases the risk of dementia, while oral health declines with cognitive decline. In this narrative review, the literature was based on the "hypothesis" that dementia and oral health have a close relationship, and appropriate oral health and occlusal rehabilitation treatment can improve the quality of life of patients with dementia and prevent progression. We conducted a literature search in PubMed and Google Scholar databases, using the search terms "dementia," "major neurocognitive disorder," "dentition," "occlusion," "tooth loss," "dental prosthesis," "dental implant," and "occlusal rehabilitation" in the title field over the past 30 years. A total of 131 studies that scientifically addressed dementia, oral health, and/or oral rehabilitation were included. In a meta-analysis, the random effect model demonstrated significant tooth loss increasing the dementia risk 3.64-fold (pooled odds ratio=3.64, 95% confidence interval [2.50~5.32], P-value=0.0348). Tooth loss can be an important indicator of cognitive function decline. As the number of missing teeth increases, the risk of dementia increases. Loss of teeth can lead to a decrease in the ascending information to the brain and reduced masticatory ability, cerebral blood flow, and psychological atrophy. Oral microbiome dysbiosis and migration of key bacterial species to the brain can also cause dementia. Additionally, inflammation in the oral cavity affects the inflammatory response of the brain and the complete body. Conversely, proper oral hygiene management, the placement of dental implants or prostheses to replace lost teeth, and the restoration of masticatory function can inhibit symptom progression in patients with dementia. Therefore, improving oral health can prevent dementia progression and improve the quality of life of patients.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.123-130
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• 2024

There are various methods for restoring the dentition of completely edentulous patients. Removable complete dentures have the advantage of being relatively economical, but they can be uncomfortable to wear. With the introduction of implant prosthodontics, various options such as implant-supported overdentures and hybrid prostheses have become available. If there is inadequate remaining ridge or limited financial resources, an overdenture supported by a few implants with additional attachments may be more suitable. In this case, due to severe peri-implantitis and other complications, the implants were removed. Subsequently, four implants (two on each side) were placed in the maxilla and a milled-bar with attachment was fabricated for each side of the maxilla.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.152-157
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• 1997

From August 1986 until June 1995, single aortic valve replacement was performed in 65 patients at the Chonnam National University Hospital. worthy-eight were male and 17 were female patients, ranging from 19 to 68 years of age(median : 43 years). The causes of the valve lesions were rheumatic in 29 patients (44.6%), bicuspid aortic valve in 6 patients (6.2%), endocarditis in 6 patients(6.2%), unknown in others. Concomitant surgical procedures were performed in 10 patients : repair of congenital defect in 5, pericardiectomy in 1, coronary artery bypass grafting in 1, noncoronary sinus plication in 1, Valsalva sinus aneurysmectomy in 1, subaortic membrane resection in 1 Used valves were 51. Jude-Medical valve in 42, Duromedics valve in 22, Bjork-Shiley valve in 2, Carpentier-Edward valve in 1. There were 3 hospital deaths (4.6%), and 2 late deaths (3.2%). Follow-up was 95.2% complete. The 10-year acturlal survival rate was 85.3%. Postoperative complications were low cardiac utput in 8, arrythmia in 5, valve related hemolysis in 1, cerebral infarction in 1, and gastrointestinal bleeding in 2. Reoperation was performed in 4 for surgical bleeding, in 3 for paravalvular leak. The mean improvement in New York Heart Association functional class is from 2.79 $\pm$ 0.66 preoperatively to 1.25 $\pm$ 0.49 postoperatively(p < 0.001) The change of cardiothoracic ratio from preoperative to postoperative is 0.57 $\pm$ 0.06 to 0.54 $\pm$ 0.05 (p < 0.05). The left ventricular ejection fraction change is not significant perioperatively. There are no mechanical failures. This early and intermediate-term follow-up suggests that in adults in whom valve repair is not possible, the mechanical valve is a reliable and durable prosthesis with good hemodynamic function and a low rate of thromboembolic event.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.891-898
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• 1997

Between May 1984 and January 1996, 130 patients were replaced cardiac valve using 150 St. Jude Medical prosthetic valves(42 aortic, 68 mitral, 20 aortic and mitral valve replycements). Follow-up was 97.6% complete. The early mortality rate was 5.4%, and late mortality rate was 4.9%. The valve-related late mortality rate was 3.3%. Of late complications, there were 6 anticoagulant related hemorrhages, 4 thromboembolisms and 1 paravalvular leakage. Linearized rates of late complication and valve-related late mortality were as follows: total late complications, .1.68o per patient-year: anticoagulant related hemorrhages, 0.92% per patient-year: thromboembolism, 0.61% per patient-year: paravalvular leakage, 0.15% per patient-year: reoperation, 0.15% per patient-year: and valve-related late mortalities, 0.61% per patient-year. Actuar al event free rate at 10 years was 87.4 $\pm$ 3.2%. The overall actuarial survival rate was 90.4$\pm$2.7% at 5 years, 87.5$\pm$3.3% at 10 years. Ninety eight percent of the survivors were in the New York Heart Association functional class I or II at the end of follow-up. There was significant improvement of cardiothoracic ratio. In conclusion, this study suggests the excellent durability of the St. Jude Medical Heart valve and remarkable functional benefit for the majority of the patients. However, prosthesisrelated complications are still common. Outcome is strongly related to the patient's preoperative cardiac condition and to the adequacy of anticoagulation control.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.900-905
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• 2006

Background: Homografts and bioprostheses are most commonly used for Rastelli operation in congenital heart disease, but the limited durability is responsible for multiple reoperations associated with increased morbidity This study evaluated long-term results after Rastelli operation with a mechanical valved conduit. Material and Method: A total of 20 patients underwent Rastelli operation with mechanical valved conduit from January 1990 to July 1992. Operative mortality was 1 of 20 patients, and a retrospective review of 19 patients(10 males, 9 females) was done. Initial diagnosis was congenitally corrected transposition of great arteries(cc-TGA, n=4), complete TGA (n=2), ventricular septal defect with pulmonary atresia(VSD with PA, n=9), truncus arteriosus(n=2), double outlet right ventricle with pulmonary stenosis(DORV with PS, n=2). The mean age at Rastelli operation was $4.6{\pm}3.4$ years, and mean follow-up period was $12.8{\pm}2.7$ years. Patients underwent Rastelli opearation using 16 CarboMedics mechanical valve, and 3 Bjork-Shiley mechanical valve($17{\pm}2$ mm). Result: There were 15 reoperations for failed mechanical valved conduit. The freedom from reoperation at 5 and 10 years was 53% and 37%. Most patients were received oral anticoagulation with warfarin, and maintained the international normalized ratio(INR) of 1.5 to 2.0. There was no anticoagulation or thromboembolism related complication. There was a significant difference in the causes of a conduit failure between early(within 3 years) and late(after 3 years) failure groups. The six patients reported early prosthetic valve failure, mainly due to valvular dysfunction by thrombosis or pannus formation. The other nine patients reported late prosthetic valve failure, mainly due to dacron conduit stenosis at anastomosis sites, whereas their valvar motion was normal except 1 patient. Conclusion: To avoid early prosthetic valve failure, strict anticoagulation therapy would be helpful. About the late development of obstructive intimal fibrocalcific peels within the Dacron conduit, an improvement of conduit material is necessary to reduce late prosthetic valve failure. In selected patients, the long term results were satisfactory.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.149-159
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• 2011

Restoring and replacing teeth with fixed prostheses commonly used in dental practice. Because of improper oral hygiene care and inaccurate laboratory procedure, complication of fixed prostheses was found in the mouth of patient. Although many efforts have been continually made to obtain the data of long term prognosis of fixed prostheses, it was difficult to do it. The purpose of this study was to evaluate the clinical status of fixed prostheses to improve the quality of dental care. In order to assess the clinical status of fixed prostheses, a total of 154 individuals (aged 22-82, 88 women and 66 men loaded with 578 unit of fixed prostheses, and 423 abutments) who visited the Department of Prosthodontics, Pusan National University Hospital, between January 2009 to December 2009 and removed old fixed prostheses were examined. The results of this study were as follows: 1. Length of service of fixed prostheses was $10.3{\pm}05.5$ years (mean), 10.0 years (median). 2. Location of fixed prostheses was found to have statistically significant influence on longevity of fixed prostheses (P<.05). The longevity of fixed prostheses was high in anterior-posterior combination region (mean:13.1, median:13.5) than anterior and posterior region. 3. Longevity of fixed prostheses made of metal was longest (mean:13.3, median:12.3). 4. Number of units in fixed prostheses was found to have no statistically significant influence on longevity of fixed prostheses (P>.05). 5. Condition of opposing dentition was found to have statistically significant influence on longevity of fixed prostheses (P>.05). The fixed prostheses lasted longest when opposed by complete denture (mean:17.1, median:19.7), removable partial denture, fixed prosthesis and natural dentition trailing behind (P<.05) 6. Periodontal disease (37.5%), dental caries (19.0%), defective margin (18.4%) were frequent complications. In 33.1% of the cases, abutment state after removing fixed prostheses was needed to be extracted.

• Korean Journal of Dental Materials
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• v.44 no.3
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• pp.207-216
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• 2017

The effect of cooling rate on precipitation hardening of a Pd-Cu-Ga-Zn metal-ceramic alloy during porcelain firing simulation was investigated and the following results were obtained. When the cooling rate was fast (Stage 0), the hardness of the alloy increased at each firing step and the high hardness value was maintained. When the cooling rate was slow (Stage 3), the hardness was the highest at the first stage of the firing, but the final hardness of the alloy after complete firing was lower. The increase in hardness of the specimens cooled at the cooling rate of Stage 0 after each firing step was caused by precipitation hardening. The decrease in hardness of the specimens cooled at the cooling rate of Stage 3 after each firing step was attributed to the coarsening of the spot-like precipitates formed in the matrix and plate-like precipitates. The matrix and the plate-like precipitates were composed of the $Pd_2(Cu,Ga,Zn)$ phase of CsCl-type, and the particle-like structure was composed of the Pd-rich ${\alpha}$-phase of face-centered cubic structure. Through the porcelain firing process, Cu, Ga, and Zn, which were dissolved in Pd-rich ${\alpha}$ particles, precipitated with Pd, resulting in the phase separation of the Pd-rich ${\alpha}$ particles into the Pd-rich ${\alpha}^{\prime}$ particles and ${\beta}^{\prime}$ precipitates composed of $Pd_2(Cu,Ga,Zn)$. These results suggested that the durability of the final prosthesis made of the Pd-Cu-Ga-Zn alloy can be improved when the cooling rate is fast during porcelain firing simulation.