• The Journal of Advanced Prosthodontics
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• 제12권2호
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• pp.67-74
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• 2020

PURPOSE. This study evaluated the influence of prosthesis weight and number of implants on the bone tissue microstrain. MATERIALS AND METHODS. Fifteen (15) fixed full-arch implant-supported prosthesis designs were created using a modeling software with different numbers of implants (4, 6, or 8) and prosthesis weights (10, 15, 20, 40, or 60 g). Each solid was imported to the computer aided engineering software and tetrahedral elements formed the mesh. The material properties were assigned to each solid with isotropic and homogeneous behavior. The friction coefficient was set as 0.3 between all the metallic interfaces, 0.65 for the cortical bone-implant interface, and 0.77 for the cancellous bone-implant interface. The standard earth gravity was defined along the Z-axis and the bone was fixed. The resulting equivalent strain was assumed as failure criteria. RESULTS. The prosthesis weight was related to the bone strain. The more implants installed, the less the amount of strain generated in the bone. The most critical situation was the use of a 60 g prosthesis supported by 4 implants with the largest calculated magnitude of 39.9 mm/mm, thereby suggesting that there was no group able to induce bone remodeling simply due to the prosthesis weight. CONCLUSION. Heavier prostheses under the effect of gravity force are related to more strain being generated around the implants. Installing more implants to support the prosthesis enables attenuating the effects observed in the bone. The simulated prostheses were not able to generate harmful values of peri-implant bone strain.

• 대한치과기공학회지
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• 제28권2호
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• pp.347-353
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• 2006

The Purpose of this study was to compare the distribution of implant fixtures according to length and diameter between screw-retained and cement-retained implant-supported fixed prosthesis and to asses whether prosthesis retained types affected the selection of size of implant fixtures. This study presents a follow-up 2,416 implant-supported fixed type prosthesis that have been screw retained or cemented retained for about 10 years in 14 dental clinics. Included in the study were 458 men and 397 women and implant fixtures used in this study were screw retained type 1,057 and 1,359 of cemented retained type. The statistical results among the diameter types of fixture by prosthesis retained type was no significant difference noted (P= 0.809) and there was significant differences was enough to among the lengths of fixture by prosthesis retained type (P= 0.020). However there were no significant difference among the fixture diameter types and length by prosthesis retained type (P= 0.486). So there was not affected to prostheis fixation mechanism for the size of implant fixtures.

• Journal of Korean Dental Science
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• 제16권2호
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• pp.105-114
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• 2023

The axial contour and proximal contact of the prosthesis affect periodontal health, food impaction, and patient satisfaction. This narrative review provides a summary of articles regarding the axial contour and proximal contact of a fixed dental prosthesis on periodontal health and physiologic function. By acquiring a comprehensive understanding of the axial contour and proximal contact of teeth and prostheses, as well as their functional significance, the virtual design of fixed dental prosthesis can be optimized to maintain periodontal health and promote physiologic function effectively.

• The Journal of Advanced Prosthodontics
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• 제3권3호
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• pp.172-176
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• 2011

Surgical resection of the mandible due to presence of benign or malignant tumor is the most common cause of the mandibular deviation. Depending upon the location and extent of the tumor in the mandible, various surgical treatment modalities like marginal, segmental, hemi, subtotal, or total mandibulectomy can be performed. The clinicians must wait for extensive period of time for completion of healing and acceptance of the osseous graft before considering the definitive prosthesis. During this initial healing period prosthodontic intervention is required for preventing the mandibular deviation. This case report describes early prosthodontic management of a patient who has undergone a reconstructed hemi-mandibulectomy with modified mandibular guide flange prosthesis. The prosthesis helps patient moving the mandible normally without deviation during functions like speech and mastication.

• 대한치과기공학회지
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• 제33권4호
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• pp.369-378
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• 2011

Purpose: This study was carried out for the purpose of obtaining basic data necessary for developing the future oral health promotion program of the elderly by surveying the actual condition of managing dental prosthesis in the elderly. Methods: It collected materials targeting 346 elderly brackets in over 65 years old who dwell in Seoul and Gyeonggi-do Province for about 10 months from September 2010 to June 2011, analyzed 312 copies except 34 copies, which are inappropriate for data processing due to being insufficient in response among these things, and obtained the following results. Results: In the actual condition of missing tooth, a case of missing tooth was indicated to be 78.8%. In case of missing tooth, the number of missing teeth was indicated to be 75.6% for under 5 pieces and 19.1% for over 21 pieces. In the actual condition of managing prosthesis, a case with dental prosthesis treatment was indicated to be 77.6%. A kind of prosthesis was indicated to be the highest in fixed partial dentures with 36.5%. In a method of rinsing dentures, 47.7% of the elderly responded as saying of washing it out with water. The appearance of removing dentures at night was indicated to be the highest in doing so with 63.1%. Satisfaction with prosthesis of being mounted now was indicated to be moderate with 50.4%. As for the appearance of having experience of education on how to manage prosthesis, it was indicated to be high with 50.4% in having none. In a kind of prosthesis depending on averagely monthly income, the ratio of total dentures was high when averagely monthly income is low. On the other hand, a case with high income was indicated to have high ratio in implants. The satisfaction with prosthesis was low when averagely monthly income is low. Also, in the experience of education on how to manage prosthesis, the ratio of responses as saying of having no experience of education on how to manage prosthesis was indicated to be high when averagely monthly income is low. Conclusion: Examining the above results, a developmental plan is considered to be necessary such as developing continuous and systematic oral health promotion program for managing elderly people's managing dental prothesis.

• 대한치과기공학회지
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• 제31권3호
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• pp.59-66
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• 2009

In this study 240 geriatric patients, aged 60 year and over were evaluated using a questionnaire and oral examination for their oral status, demand and satisfaction of prosthesis treatment. 1. The single main complaint was regarding from the existing removable prosthesis. When the complaints were catagorized into larger groups, complaints regarding existing prosthesis were 32% and followed by 30% in caries and endodontic problems. 2. DMFT index woman appeared the man the age when will increase more highly recording where highly and considered statistically. 3. According to the result from questionnaire, 48% of patients wearing removable prosthesis and 43% with fixed prosthesis were not satisfied with existing prosthesis. Thirty-seven percentages of patients were not satisfied with aesthetics and unable to chew food properly. 4. Thirty-nine percentage of patients were wearing removable prosthesis. More complete dentures were found on maxilla and partial dentures on mandible. 5. Seventy-seven percentage of patients requested for new prosthesis and the majority of these patients had complaints of difficulties in chewing and discomfort.

• The Journal of Advanced Prosthodontics
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• 제15권4호
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• pp.202-213
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• 2023

PURPOSE. This prospective clinical study was conducted to evaluate the clinical usefulness of the freely detachable zirconia ball- and spring-retained implant prosthesis (BSRP) through a comparative analysis of screw- and cement-retained implant prosthesis (SCRP). MATERIALS AND METHODS. A multi-center, randomized, prospective clinical study evaluating the clinical usefulness of the detachable zirconia ball- and spring-retained implant prostheses was conducted. Sixty-four implant prostheses in 64 patients were examined. Periodic observational studies were conducted at 0, 3, 6, and 12 months after delivery of the implant prosthesis. Factors such as implant success rate, marginal bone resorption, periodontal pocket depth, plaque and bleeding index, and prosthetic complications were evaluated, respectively. RESULTS. During the 1-year observation period, all implants survived without functional problems and clinical mobility, showing a 100% implant success rate. Marginal bone resorption was significantly higher in the SCRP group than in the BSRP group only at the time of implant prosthesis delivery (P = .043). In all observation periods, periodontal pocket depth was slightly higher in the BSRP group than in the SCRP group, but there was no significant difference (P > .05). The modified plaque index (mPI) scores of both groups were moderate. Higher ratio of a score 2 in modified sulcus bleeding index (mBI) was observed in the BSRP group in the 6- and 12-months observation. CONCLUSION. Within the limitations of this study, the newly developed zirconia ball- and spring-retained implant prosthesis could be considered as an applicable and predictable treatment method along with the existing screw- and cement-retained prosthesis.

• Structural Engineering and Mechanics
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• 제55권1호
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• pp.65-78
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• 2015

In recent years, implants have gained growing importance in all areas of medicine. The success of the treatment depends on many factors affecting the bone-implant, implant-abutment and abutment-prosthesis interfaces. In this paper, static and dynamic behaviors of the dental prosthesis are investigated. Three-dimensional finite element models of dental prosthesis were constructed. Dynamic loads in 5 sec applied on occlusal surface. Therefore, FEA was selected for use in this study to examine the effect of the static and dynamic loads on the stress distribution for an implant-supported fixed partial denture and supporting bone tissue.

• The Journal of Advanced Prosthodontics
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• 제4권4호
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• pp.235-238
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• 2012

Facial prosthesis is generally considered over surgical reconstruction to restore function and appearance in patients with facial defects that resulted from cancer resection. Retention of the prosthesis is challenging due to its size and weight. Retention can be achieved by using medical grade adhesives, resilient attachments, clips and osseointegrated implants. It can also be connected to obturator by magnets. This clinical report highlights the rehabilitation of a lateral midfacial defect with a two piece prosthesis that included an extra oral facial prosthesis and an intraoral obturator with the use of magnets.

• 대한치과기공학회지
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• 제42권4호
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• pp.409-417
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• 2020

This case study is aimed at introducing a full-mouth rehabilitation of a patient with severe tooth wear using fixed prosthesis. This is a case report of a patient with severe wear dentition with changing vertical dimension. In line with using prosthetic treatment, patient adaptation was verified with provisional restorations followed by diagnostic wax-up. Function, esthetics, and occlusal stability were verified during a 4-week follow up period. Prosthodontic reconstruction based on systemic analysis, diagnosis, and treatment plan led to satisfactory results after delivery of definitive prosthesis. Prosthetic treatment of severe wear dentition was functionally and esthetically successful. Dentists and dental technicians would be able to develop better treatment approaches using fixed dental prosthesis.