• The Journal of the Korean dental association
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• v.56 no.9
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• pp.462-478
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• 2018

The presence of implant-prosthesis misfits can cause various complications. It is very important to detect misfits to prevent such complications. There are various evaluation methods for misfit assessment including clinical methods and laboratory in vitro methods. The clinical misfit evaluation includes radiographic analysis, visual observation, probing, Sheffield test, evaluation with disclosing materials, and screw resistance test. The laboratory in vitro evaluation method includes indirect modelling evaluation and direct metrological visualization. Of the indirect modelling methods, photoelastic stress analysis, finite element analysis, strain gauge analysis, and microbial colonization analysis were reviewed. Of the direct metrological visualization, microscopic analysis, 3-D photogrammetric analysis, coordinate measuring analysis, and radiographic analysis were reviewed. In this review, the characteristics, advantages and disadvantages of each method were evaluated.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.3
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• pp.225-231
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• 2018

Down syndrome patients generally have poor oral hygiene due to lack of awareness and ability to perform oral care, and there is a high risk of tooth loss. Also, they are characterized by small and irregular teeth and oligodontia, which makes it difficult to do prosthetic treatment. This article reports a case of implant hybrid prosthesis treatment of maxillary edentulous area in Down syndrome patient. The external shape of the final prosthesis was determined by using the mandibular artificial teeth to reflect the oligodontia of the mandible and the pontic areas were adjusted to facilitate oral hygiene care. As a result, aesthetically and functionally satisfactory results were obtained.

• Journal of Korean Dental Science
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• v.10 no.2
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• pp.87-95
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• 2017

This case study was to report the possible increase in the denture retention and psychological relief using the implant-supported fixed prostheses in a completely edentulous patient. The implants were placed in the anterior portion of the mandible in a patient who had completely edentulous state following the extraction of residual abutment teeth, and consequently a distal extension removable partial denture was fabricated. The patient's adaptation and satisfaction to the new prosthesis was monitored and confirmed in terms of masticatory function and esthetics, by restoring the oral condition similar to initial status before the residual teeth extraction. After 6 months, radiographic examination confirmed that both the abutment teeth and the implants were stable and well maintained. Considering the relatively short clinical follow-up period, however, continuous long-term monitoring was required.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.3
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• pp.235-242
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• 2018

Periodontal and prosthodontic maintenance of implant overdenture is a very important factor for the long term success of the prosthesis and implants. Failure of maintenance can lead to prosthetic failure due to peri-implant bone loss and fracture and wear of the prosthesis or components. In this case, the existing gold milled bars were reconstructed with cobalt chrome milled bar in a manner that does not interfere with the external shape for the retreatment of fractured implant overdenture by maintenance failure. Two implants of mandible were selected strategically and the CM LOC attachments were connected to the two implants, and implant overdentures were fabricated. As a result, prosthesis with a functional and esthetic design that facilitates good hygiene management of the patient was delivered, which is advantageous for long term maintenance, and regular check-ups were scheduled for proper maintenance.

• The Journal of the Korean dental association
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• v.53 no.6
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• pp.418-426
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• 2015

The appropriate occlusion is one of the most important factors for the long-term success of implant and its restorations. The purpose of this review is to investigate and define occlusal considerations to reduce failure of implant prostheses. The physiological movement of implants is markedly lower than that of natural teeth and they also lack in occlusal sensitivity. Proper occlusal pattern may be assigned to compensate for the biological disadvantages and occlusal contacts must be formed where the cantilever effect is minimized. Moreover, the long-term success of implants after osseointegration can be assured by reducing early occlusal loading to avoid implant overloading and selecting appropriate occlusion material. Occlusal overload was brought by the number and location of occlusal contacts, which are under the clinician's control. The concept of implant occlusion is based on the concepts derived from traditional prosthetics. Moreover, there are few evidence on the concept or design of implant occlusion. Several occlusal design was recommended for implant prosthesis. Mutually protected occlusion, group function occlusion and bilateral balance occlusion was recommended for the specific types of implant restorations. This article reviews proper design of occlusion for implant restoration and offers occlusion strategy clinically.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.2
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• pp.105-108
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• 2003

After stage-two surgery, the highest incidence of failure has been attributed to implant overload. However, the biomechanical factors cited inthe literature that contribute to implant overload, such as bone type, cuspal inclination, horizontal offset, maxillary compared to mandibular arch, the inclusion of natural teeth within the prosthesis, and occlusal harmony are superimposed on physiologic variations. Following two cases, including reduction of cuspal inclination and usage of modified incisal pin, showed a method of contouring occlusal surface for reduction of unpreditable implant overload.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.10 no.2
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• pp.21-30
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• 2001

Fiber reinforced materials have favorable mechanical properties. Moreover, the strength to weight ratios of this material is superior to those of most alloys. Comparing to the metals, it showed many other advantages as well, including non-corrosiveness, translucency and easy repair characteristic. Since, it has the potential for the chair-side and laboratory fabrication, it is not surprising that fiber reinforced composites offer the potential for use in various applications in dentistry. To make the well-fitted restorations, Fiber reinforced composite (FRC) has been suggested as an alternative framework material for the implant supported fixed prosthesis. Two fixed partial denture fabrication procedures were tried. Vectris fiber was pressed to the EsthetiCone gold cylinder on the implant positioned cast. And then, Targis were added on it. In the other method, we used the customized component using UCLA abutment. The beads for retaining the Vectris fiber were added on the abutment. If careful laboratory and clinical techniques were done, these two techniques would fulfill the demands of the esthetics and strength.

• The Journal of the Korean dental association
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• v.54 no.9
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• pp.692-702
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• 2016

A short dental implant is considered as possible solution in difficult clinical situations for the placement of a regular length implant. Using a short implant avoiding more invasive surgical procedures simplifies the treatment plan and shortenes the duration of treatment. In this case, 71-year-old female came up with discomfort from her old mandibular denture. As she had fully edentulous mandible and got a negative feedback from removable denture, implant-supported fixed prosthesis was planned. Six short implants were placed on her mandible with severe alveolar bone loss. After 1 year follow up period, implants were well retained with any other abnormal findings. The patient was satisfied with her prostheses and satisfactory outcomes were attained in terms of both esthetic and functional clinical results.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.79-87
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• 2021

The digital workflow of optical impressions by the intraoral scanner and CADCAM manufacture of dental prostheses is actively developing. The complex process of traditional impression taking, definite cast fabrication, wax pattern making, and casting has been shortened, and the number of patient's visits can also be reduced. Advances in intraoral scanner technology have increased the precision and accuracy of optical impression, and its indication is progressively widened toward the long span fixed dental prosthesis. This case report describes the long span implant case, and the operator fully utilized digital workflow such as computer-guided implant surgical template and CAD-CAM produced restoration after the digital impression. The provisional restoration and customized abutments were prepared with the optical impression taken on the same day of implant surgery. Moreover, the final prosthesis was fabricated with the digital scan while utilizing the same customized abutment from the provisional restoration. During the data acquisition step, stl data of customized abutments, previously scanned at the time of provisional restoration delivery, were imported and automatically aligned with digital impression data using an 'A.I. abutment matching algorithm' the intraoral scanner software. By using this algorithm, it was possible to obtain the subgingival margin without the gingival retraction or abutment removal. Using the digital intraoral scanner's advanced functions, the operator could shorten the total treatment time. So that both the patient and the clinician could experience convenient and effective treatment, and it was possible to manufacture a prosthesis with predictability.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.2
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• pp.238-247
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• 2004

Statement of problem: Major objective in making on implant-supported prosthesis is the production of superstructure that exhibits a passive fit when connected to multiple abutments. One requirement to ensure passive fit is to make an accurate impression. Purpose : The purpose of this study was to compare the accuracy of master cast fabricated by using different impression methods at the different impression levels. Material and method: The master model used in this study was resin block having low implant analogs. Impression method studied were 1) direct method on fxiture level (Group FIX-D), 2) indirect method on fixture level(Group FIX-I), 3) modified indirect method on fixture level(Group FIX-M), 4) direct method on abutment level(Group AB-D) and 5) indirect method on abutment level(Group AB-I). Each of the five groups took 10 impressions. Fifty impressions were made for master cast by using Impregum $F^{(R)}$ impression material loaded on individual tray. Three dimensional measuring microscope was used to measure the inter-implant distance. Error rate of each inter-implant distance were calculated and evaluated. Results : The results were as follows. 1. Group FIX exhibited higher accuracy than group AB. 2. In group FIX, modified indirect method showed the highest accuracy, while indirect method showed the lowest accuracy. In group Ab, indirect method showed the higher accuracy than direct method. 3. Group FIX showed larger horizontal error than group AB. But, group AB showed the larger vertical error than group FIX. 4. Group Fix-M showed smallest vertical and horizontal error. Conclusion: An impression method have more effect on accuracy of master model than an impression level. A modified indirect method showed smallest vertical and horizontal error.