• The Journal of Korean Academy of Prosthodontics
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• v.43 no.1
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• pp.120-131
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• 2005

Statement of problem. More than 70% of patients who need the implant supported restoration are parially edentulous. The principles of design for implant supported fixed partial denture in mandibular posterior region are many and varied. Jurisdiction for their use is usually based on clinical evaluation. There are several areas or interest regarding the design of implant supported fixed partial denture in mandibular posterior region. 1) Straight and tripod configuration in implant placement, 2) Two restoration types such as individualized and splinted restorations. Purpose. The purpose of this study was to compare the amount and distribution of stress around the implant fixtures placed in the mandibular posterior region with two different arrangements and to evaluate the effects of splinting using the photoelastic stress analysis. Material & methods. 1) Production of study model: Mandibular partially edentulous model was waxed-up and duplicated with silicone and two models were poured in stone. 2) Fixture installation and photoelastic model construction: Using surveyor(Ney, USh), 3 fixtures(two 4.0 $\times$13 mm, one 5.0$\times$10 mm, Lifecore, USA) were insta)led in straight & tripod configurations. Silicone molds were made and poured in photoelastic resin (PL-2. Measurements group, USA). 3) Prostheses construction: Four 3-unit bridges (Type III gold alloy, Dongmyung co., Korea) were produced with nonhexed and hexed UCLA abutments and fitted with conventional methods. The abutments were tightened with 30 Ncm torque and the static loads were applied at 12 points of the occlusal surface. 4) Photoelastic stress analysis : The polarizer analyzer system with digital camera(S-2 Pro, Fujifilm, Japan) was used to take the photoelastic fringes and analysed using computer analysis program. Results. Solitary hexed UCLA restoration developed different stress patterns between two implant arrangement configurations, but there were no stress transfer to adjacent implants from the loaded implant in both configurations. However splinted restorations showed lesser amount of stresses in the loaded implants and showed stress transfer to adjacent implants in both configurations. Solitary hexed UCLA restoration with tripod configuration developed higher stresses in anterior and middle implants under loading than implants with straight configurations. Splintied 3 unit fixed partial dentures with tripod configuration showed higher stress development in posterior implant under loading but there were no obvious differences between two configurations. Conclusions. The tripod configuration of implant arrangement didn't show any advantages over the straight configuration. Splinting of 3 unit bridges with nonhexed UCLA abutments showed less stress development around the fixtures. Solitary hexed UCLA restoration developed tilting of implant fixture under offset loads.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.242-252
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• 2015

Implant overdenture treatment using several solitary attachment systems on mandibular edentulous patients. Most patients with severe residual ridge resorption report significantly more problems adapting to their mandibular denture due to a lack of comfort, retention, stability and to the inability to chew and eat. Recent scientific studies carried out over the past decade have determined that the benefits of a mandibular implant overdenture are sufficient to get retention and stability. Therefore, overdenture with implants on the mandible and attachments are considered as a treatment of choice as a favorable treatment. In this cases, with consideration for jaw relation, level of bone loss, facial support and economic factor, edentulous patients with severe residual ridge resorption are rehabilitated by complete denture on maxilla and two-implants overdenture using several solitary attachment systems on mandible.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.2
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• pp.164-172
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• 2021

Purpose: The purpose of this study was to analyze the level of interest that common Internet users have in dental implant using a Google Trends, and to compare the level of interest with big data from National Health Insurance Service. Materials and methods: Google Trends provides a relative search volume for search keywords, which is the average data that visualizes the frequency of searches for those keywords over a specific period of time. Implant was selected as the search keyword to evaluate changes in time flows of general Internet users' interest from 2015 to 2019 with trend line and 6 month moving average. Relative search volume for implant was analyzed with the number of patients who received National Health Insurance coverage for implant. Interest in implant and conventional denture was compared and popular related search keywords were analyzed. Results: Relative search volume for implant has increased gradually and showed a significant positive correlation with the total number of patients (P<.01). Interest in implant was higher than denture for most of the time. Keywords related to implant cost were most frequently observed in all years and related search on implant procedure was increasing. Conclusion: Within the limitations of this study, the public interest in dental implant was gradually increasing and specific areas of interest were changing. Web-based Google Trends data was also compared with traditional data and significant correlation was confirmed.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.5
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• pp.633-643
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• 2007

Statement of problem: Recently there are on an increasing trend of using implants-especially in edentulous mandible of severly alveolar bone recessed. Purpose: The aim of this study was to analyze the displacement and stress distribution of various mandibular implant-retained overdenture models supported by two implants in interforaminal region under the occlusion scheme load. Material and method: FEA models were made by the 3D scanning of the edentulous mandibular dentiform. The three models were named as Model M1, M2, and M3 accord ing to the position of implants: M1, Lt. incisor area, M2, Canine area, and M3, 1st Premolar area. Inter-implant angulation model was named as M4. Conventional complete denture was named M5 and used as a control group. Ball implant and Gold matrice were used as a retentive anchors. The occlusion type loads were applied horizontally over each tooth. Results: 1. In mandibular implant retained overdenture Canine Protected Occlusion type load resulted in higher levels of stress to the implants and female matrices than other types of loads. 2. The overdenture model M1, with implants in lateral incisor areas resulted in lower stress concentration to the implants and female matrices than other models. 3. In mandibular implant retained overdenture the stresses of the implant and female matrice were lower in mesially inclined implant than these of parallel installed implant. Conclusion: Lateral incisor areas could be the best site for the implants in mandibular implant-retained overdenture. The mandibular implant retained overdenture models mentioned above showed to the lowest stress to the implants and female matrices.

• The Journal of the Korean dental association
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• v.50 no.3
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• pp.110-117
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• 2012

Dental computer-aided design (CAD) and computer-aided manufacturing (CAM) technology have rapidly progressed over the past 30 years. The technology, which can be used in the dental laboratory, the dental office and the form of production centers, has become more common in recent years. This technology is now applied to inlays, onlays, crowns, fixed partial dentures, removable partial denture frameworks, complete dentures, templates for implant installation, implant abutments, and even maxillofacial prostheses. Dentists and dental technicians, who want to use these techniques, should have certain basic knowledge about that. This article gives an overview of CAD/CAM technologies, histories and how it applies in prosthetic dentistry.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.1
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• pp.34-47
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• 2007

Statement of problem: Conventional mandibular complete denture lacks in support and stability for edentulous patients to use. Purpose: To enhance support and stability of mandibular complete denture, 2 implants were inserted on the inter-mental foramina space of edentulous patients. With 2 magnetic attachments on the inner side of the overdenture, we gave immediate loads and evaluated the stability of the implants, the responses of the supporting tissues, and the satisfaction of the patients. Material & methods: 6 edentulous patients (5 male, 1 female) each recieved 2 SLA implants in the inter-mental foramina region and implants were immediately loaded with overdenture with magnet attachments. To evaluate the implants stability and the peri-implant tissues, clinical exams, RFA tests and radiographic exams were preformed at the 1 week, 2wks, 6wks, 12wks, and 24wks. post- surgery. Results: The mean surgery time was $45.7{\pm}7.7mins$., while the denture delivery time was $45.5{\pm}12.6mins$. Only 2 of 14 implants were failed. Survived implants that remained were clincally and radiographically stable. Mean ISQ values were relatively stable, showing $69.71{\pm}5.55$, $69.00{\pm}9.48$, $67.92{\pm}7.86$, $67.92{\pm}9.58$, $70.08{\pm}7.61$, $71.92{\pm}6.43$ at the 1 wk, 2 wks, 6 wks, 12 wks, 24 wks. follow up check. Crestal bone changes were $-1.18mm{\pm}0.68mm$, $-1.35{\pm}0.69mm$, $-1.47{\pm}0.68mm$ at the 6wks, 12wks, 24wks. follow up check. Bleeding on probing(BOP index) was not significant. Conclusion: Mandibular ovedentures with 2 magnetic attachments over two interforaminal implants on edentulous patients for immediate function is a recommendable novel treatment for edentulous patients which shows stability on the implants and supporting tissue.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.223-231
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• 2011

The purpose of this case report is to introduce new attachment system(milled titanium bar with $Locator^{(R)}$ attachment) for implant supported overdenture in maxillary edentulous patients. A 56-years-old male patient visited the hospital due to the mobility of his maxillary fixed partial dentures(10-unit bridge). Including temporomandibular joint(TMJ), there was no specific PMHs to influence dental treatment. In radiographic and clinical evaluation, there was a severe bone resorption and mobility in maxillary teeth. Accordingly all the remaining maxillary teeth was extracted and fabrication of implant supported overdenture was planned. The milled titanium bar with $Locator^{(R)}$ was designed as an attachment system, considering the stability and retention of denture, masticatory efficiency, oral hygiene care, esthetics, pronunciation, and patient's financial state. The milled titanium bar was manufactured using CAD/CAM technology, and $Locator^{(R)}$ attachment connected to the bar by tap & drill method. For over 1-year, in terms of function and esthetics, satisfactory result was obtained.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.1
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• pp.77-87
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• 2018

Prosthetic treatment using implants in fully edentulous patients includes implant-supported fixed prosthesis, implant hybrid prosthesis, implant retained- or supported-over-denture and implant supported fixed prosthesis has advantages such as psychological stability, pronunciation. If an implant supported fixed prosthesis is planned, the implants should be placed in consideration of pronunciation, esthetics, and oral hygiene. For this, clinical and radiological diagnosis is indispensable. When placing the prosthetic driven implant at the site determined from the diagnosis, a sufficient amount of alveolar bone and soft tissue support are required. If these requirements found to be insufficient, a wide range of bone grafting should be performed in advance. In this case, a fully edentulous patient with severe alveolar bone resorption due to periodontal disease was treated with a full mouth rehabilitation using implant-supported fixed prosthesis preceding maxillary sinus graft and alveolar bone augmentation. We report this patient were satisfied with esthetic and function.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.1
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• pp.18-26
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• 2014

Purpose: The purpose of this study was to estimate the cost of dental implant using the bottom-up approach with the current data from dental clinics. Materials and methods: In this study, direct and indirect costs required for each treatment were calculated using the bottom-up approach. In the bottom-up costing, the average monthly total cost of dental clinic includes labor and material costs, administrative expenses, medical malpractice costs, and opportunity costs of invested capital. For the dental implant cost components, those include direct costs (labor costs, laboratory costs, material costs, depreciation or other operating costs), indirect costs (administrative costs), and the opportunity costs of investment for dental clinic. Results: Dental implant costs of metal crown, porcelain crown and over-denture were 1,449,000 won, 1,583,000 won, and 2,471,000 won respectively. The proportion of cost components was as follows. The labor cost were 50%, and material, administrative and other cost were 33%, 15% and 2%, respectively. For direct, indirect and investment cost, the ratio were 83%, 15% and 2%, respectively. Conclusion: The labor costs were evaluated to comprise largest proportion (about 50%, 730,000 won). Dental implant cost using Bottom-up costing was 1,450,000 won for metal crown and 1,580,000 won for porcelain crown.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.160-167
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• 2022

One of the treatment options for edentulous state patients with residual ridge resorption is implant overdenture using milled bar and attachment. It not only provides improved retention and stability but can also reduce the coverage of palatal surface. In addition, when a small number of implants are used, milled bar has the effect of being splinted between implant fixtures, which makes it mechanically advantageous under functions such as mastication. The patient in this case was a maxillary edentulous state patient with a considerable amount of residual alveolar bone resorption after removing the existing failed implants. Three implants were planted on both sides and an implant overdenture was fabricated using milled bar and ADD-TOC attachment.