• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.183-197
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• 1990

The purpose of this study was to analyse the magnitude and distribution of stresses using a Photoelastic model from and distal - extension removable partial dentures With four designed indirect retainers. The designs of the indirect retainers were as follows : Design No. 1 : Aker's clasp on 1st bicuspid with no indirect retainer. Design No. 2 : Aker's clasp on 1st bicuspid with indirect retainer on canine. Design No. 3 : Extension of the reciprocal arm of Aker's clasp toward incisal rest on canine. Design No. 4 : Connection with the indirect retainer as in No. 2 and extension of reciprocal arm of Aker' s clasp. A photoelastic model was made of the epoxy resin(PL - 1) and hardner(PLH - 1) and coated with plastic cement -1(PC -1) at the lingual surface of the epoxy model and set with chrome - cobalt partial dentures. A unilateral vertical load of 10kg to the right 1st molar and a vertical load of 10kg to the middle portion of the metal bar crossing both the 1st molars of the right and left, were applied. With the use of specially designed jig, fixture; loading device and the reflective circular polariscope, we obtained the following results : 1. When the unilateral vertical load and the vertical load of the middle portion of the metal bar were applied, design No. 2, 3 and 4 exhibited the higher stress concentration at the root apices and their surrounding tissues of the primary and secondary abutment teeth. 2. When the unilateral vertical load applied to design No. 2,3 and 4 the root apices of the primary and secondary abutment teeth and their surrounding tissues and the nonloaded side of edentulous area exhibited and even stress distribution. 3. When the vertical load was applied, the stress concentration fringe in the primary and secondary abutment teeth was in the order of No. 1,4,2 and 3. 4. No.1 and 4 exhibited the higher distrorted stress concentration at the primary teeth and the edentulous area in the nonloaded side. 5. No.2 design reduced the stresses at the apices of the alveoli of the primary abutment teeth bilaterally as well as on the crest of the residual ridge on the nonloaded side. 6. No. 2 design exhibited the most favorable stress distribution.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.1
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• pp.32-37
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• 2017

In this case report, an alternative impression technique for fabricating removable partial dentures was used in a patient with very few remaining teeth. In this technique, an individual tray was made on the cast, which was made by relining interim denture and taking overimpression with irreversible hydrocolloid according to McLean's functional impression concept. This method showed the following advantages: the no need for border molding with modeling compound, time saving for denture impression without overextension and accurate seating of the individual tray.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.4
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• pp.412-419
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• 2022

For treatment of partially edentulous patients, a treatment using implant is widely used. Treatment method using implant are implant fixed prostheses and removable partial dentures, and for patients with severe bone resorption, removable implant overdenture with the effects of aesthetic and reducing cost can be used as treatment options. Specially, prosthesis with milled-bar and attachment has the effect of being splinted between implant fixtures, higher retention and stability than conventional removable partial denture. And it has the effect of improvement of aesthetic through lip support by denture base. In this case, the patient with severe alveolar bone resorption and partial edentulous maxilla and mandible was treated by implant-assisted removable partial denture using Milled-bar and ADD-TOC attachment. The esthetic was improved by removing the clasp because of effects of additional retention by using the attachment, and reducing palatal coverage of implant-assisted removable partial denture. The clinical results were satisfactory on the aspect of aesthetic and masticatory function.

• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.409-415
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• 2013

PURPOSE. The midline fracture of maxillary complete dentures is a frequently encountered complication. The purpose of this study was to assess the effect of frenulum height on midline strains of maxillary complete dentures. MATERIALS AND METHODS. A removable maxillary complete denture was fabricated and duplicated seven times. Four different labial frenulum heights were tested for stresses occurring on the palatal cameo surface. The strains were measured with strain gauges placed on 5 different locations and the stresses were calculated. To mimic occlusal forces bilaterally 100 N of load was applied from the premolar and molar region. RESULTS. A statistically significant association between the height of the labial frenulum and the calculated stresses and strains was shown (P<.05) predominantly on the midline and especially on the incisive papilla. The results showed that stress on the anterior midline of the maxillary complete denture increases with a higher labial frenulum. CONCLUSION. Within the limitations of this in vitro study, it can be concluded that the stress on the anterior midline of the maxillary complete denture increases with a higher labial frenulum. Surgical or mechanical precautions should be taken to prevent short-term failure of maxillary complete dentures due to stress concentration and low cycle fatigue tendency at the labial frenulum region.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.3
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• pp.251-256
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• 2020

In recent years, digital technology has been developed in dentistry, which denture frameworks can be manufactured using DMLS (Direct Metal Laser Sintering) technique. A traditional impression method can be replaced by oral scanning and wax pattern production process can be achieved by the use of CAD/CAM techniques. The designed STL files can be sent to DMLS devices to fabricate final components of removable partial dentures (RPD). The advantages of digital dentistry are concision and precision. In this case study, a fracture of occlusal rests providing support and indirect retention was repaired by DMLS and laser welding techniques. It shows satisfactory results in adaptation accuracy and functional properties of the repaired denture.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.4
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• pp.375-383
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• 2018

Clinicians are faced with many difficulties when planning prosthodontic restorations with implants in a complete edentulous patient. When planning fixed implant prosthetics, it is often necessary to have additional surgery due to highly reduced alveolar bone, as well as high treatment costs and long-term treatment durations can be required. In addition, lack of interocclusal space can be a problem when planning implant supported overdentures. In this study, we planned to place a small number of implants on the anterior maxilla and used them as the abutments for distal-extension removable partial dentures on the posterior side in a maxillary fully edentulous patient. This would reduce the possibility of additional invasive operations such as alveolar bone graft, shorten the treatment time, and be relatively easy for elderly patients to burden. In this case, the patient was provided with a distal-extension removable partial denture and anterior implant fixed prostheses, which was similar to the previous one, and showed good adaptation, and chewing efficiency and esthetics was recovered.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.4
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• pp.437-447
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• 2011

In patients who used removable partial dentures for a long period of time, gradual alveolar bone resorption occurs in edentulous area. However, in residual teeth area, alveolar bone is maintained sound. This causes an imbalance in intermaxillary distance between a maxillae and a mandible which is intensified due to expansion in vertical and horizontal bone amount difference between the two area as time passes. As the result, this shows a substantial difference in vertical position according to the period of teeth loss even after residual teeth loss. As in this situation, a patient with bilaterally and anterio-posteriorly different intermaxillary distance, various prosthodontic problems can be caused in fixed implant prosthodontics and implant overdenture. This study shows a case in which implant-supported removable partial denture was fabricated considering residual alveolar bone height after teeth loss in a patient who had been using a distal extension removable partial denture for a long period of time. In anterior area with short intermaxillary distance, fixed prosthodontics were fabricated with implant placement and in posterior area with long intermaxillary distance, a removable partial denture was fabricated. Finally, a small number of implants were placed without additional surgery and economical and comfortable treatment results were shown.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.1
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• pp.67-77
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• 1997

The purpose of this study was to evaluate a cases which was treated with konus telescope on the patients in bilaterally edentulous mandible. Author made konus telescope for two patients and then X-ray and clinical examination were used for evaluation of the function and change in supporting structure of the abutment teeth during the 60months. Patient complained of difficulties in removal of denture at the beginning but they got used to it soon. X-ray showed that there were no changes in supporting structure of the abutment teeth after 60 months. It was effective in promotion of ridge soreness and also reducing the need of relining. This study suggest that konus telescope was effective for the treatment of bilaterally edentulous situations.

• The Journal of Advanced Prosthodontics
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• v.6 no.2
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• pp.138-145
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• 2014

Cobalt-Chromium (Co-Cr) alloys are classified as predominantly base-metal alloys and are widely known for their biomedical applications in the orthopedic and dental fields. In dentistry, Co-Cr alloys are commonly used for the fabrication of metallic frameworks of removable partial dentures and recently have been used as metallic substructures for the fabrication of porcelain-fused-to-metal restorations and implant frameworks. The increased worldwide interest in utilizing Co-Cr alloys for dental applications is related to their low cost and adequate physico-mechanical properties. Additionally, among base-metal alloys, Co-Cr alloys are used more frequently in many countries to replace Nickel-Chromium (Ni-Cr) alloys. This is mainly due to the increased concern regarding the toxic effects of Ni on the human body when alloys containing Ni are exposed to the oral cavity. This review article describes dental applications, metallurgical characterization, and physico-mechanical properties of Co-Cr alloys and also addresses their clinical and laboratory behavior in relation to those properties.

• Journal of Technologic Dentistry
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• v.30 no.2
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• pp.135-147
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• 2008

The results are as following. This study aimed to furnish basic data for improving the oral health of the elderly by conducting research into the relationship between denture satisfaction and the perceived oral health status of elderly people with removable dentures. The study performed research involving 246 elderly people who were living in Jeonju and Iksan, jeonbuk, and who were 65 years old or over from August 1 to December 5, 2007. The research method was a face-to-face interview. 1. The denture satisfaction of respondents for the research averaged $3.74{\pm}0.69$, and there was a significant difference in their satisfaction according to the level of education, the cohabitant family type, the procurement of living expenses, the performance of leisure activity, the period of current denture use, the number of denture changes, the experience during a dentist visit for denture maintenance, the experience of restricted activity due to annual oral diseases, and the opinions about denture prices. 2. 48.8% of respondents answered that their oral health status was good, and there was a significant difference in their satisfaction according to the procurement of living expenses, the total period of denture use, the period of current denture use, the number of denture changes, the experience of restricted activity due to annual oral diseases, and the opinions about denture prices. 3. The most highly influential variable affecting denture satisfaction was the opinions about denture prices(R=33.7%). 4. The most highly influential variable affecting the perceived oral health status was the educational level(R=17.3%). 5. As a result of analyzing the relationship between denture satisfaction and perceived oral health status, more respondents were satisfied with their dentures the more they thought their oral health status was in good shape.