• Journal of Dental Rehabilitation and Applied Science
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• 제33권4호
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• pp.307-313
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• 2017

The object of this case report is to introduce milled zirconia bar and PEKK female part made by CAD/CAM technology for bar attachment implant supported overdenture in maxillary edentulous patients. For over 2 years, in terms of function and esthetics, satisfactory result was obtained. Esthetically and functionally satisfactory results were obtained in periodic follow up check.

• The Journal of Advanced Prosthodontics
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• 제6권4호
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• pp.245-252
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• 2014

PURPOSE. To present a literature review on implant overdentures after a brief survey of bone loss after extraction of all teeth. MATERIALS AND METHODS. Papers on alveolar bone loss and implant overdentures have been studied for a narrative review. RESULTS. Bone loss of the alveolar process after tooth extraction occurs with great individual variation, impossible to predict at the time of extraction. The simplest way to prevent bone loss is to avoid extraction of all teeth. To keep a few teeth and use them or their roots for a tooth or root-supported overdenture substantially reduces bone loss. Jaws with implant-supported prostheses show less bone loss than jaws with conventional dentures. Mandibular 2-implant overdentures provide patients with better outcomes than do conventional dentures, regarding satisfaction, chewing ability and oral-health-related quality of life. There is no strong evidence for the superiority of one overdenture retention-system over the others regarding patient satisfaction, survival, peri-implant bone loss and relevant clinical factors. Mandibular single midline implant overdentures have shown promising results but long-term results are not yet available. For a maxillary overdenture 4 to 6 implants splinted with a bar provide high survival both for implants and overdenture. CONCLUSION. In edentulous mandibles, 2-implant overdentures provide excellent long-term success and survival, including patient satisfaction and improved oral functions. To further reduce the costs a single midline implant overdenture can be a promising option. In the maxilla, overdentures supported on 4 to 6 implants splinted with a bar have demonstrated good functional results.

• The Journal of Korean Academy of Prosthodontics
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• 제40권5호
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• pp.507-524
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• 2002

Load transfer of implant overdenture varies depending on anchorage systems that are the design of the superstructure and substructure and the choice of attachment. Overload by using improper anchorage system not only will cause fracture of the framework or screw but also may cause failure of osseointegration. Choosing anchorage system in making prosthesis, therefore, can be considered to be one of the most important factors that affect long-term success of implant treatment. In this study, in order to determine the effect of anchorage systems on load transfer in mandibular implant overdenture in which 4 implants were placed in the interforaminal region, patterns of stress distribution in implant supporting bone in case of unilateral vertical loading on mandibular left first molar were compared each other according to various types of anchorage system using three-dimensional photoelastic stress analysis. The five photoelastic overdenture models utilizing Hader bar without cantilever using clips(type 1), cantilevered Hader bar using clips(type 2), cantilevered Hader bar with milled surface using clips(type 3), cantilevered milled-bar using swivel-latchs and frictional pins(type 4), and Hader bar using clip and ERA attachments(type 5), and one cantilevered fixed-detachable prosthesis(type 6) model as control were fabricated. The following conclusions were drawn within the limitations of this study, 1. In all experimental models. the highest stress was concentrated on the most distal implant supporting bone on loaded side. 2. Maximum fringe orders on ipsilateral distal implant supporting bone in a ascending order is as follows: type 5, type 1, type 4, type 2 and type 3, and type 6. 3. Regardless of anchorage systems. more or less stresses were generated on the residual ridge under distal extension base of all overdenture models. To summarize the above mentioned results, in case of the patients with unfavorable biomechanical conditions such as not sufficient number of supporting implants, short length of the implant and unfavorable antero-posterior spread. selecting resilient type attachment or minimizing distal cantilever bar is considered to be appropriate methods to prevent overloading on implants by reducing cantilever effect and gaining more support from the distal residual ridge.

• Journal of dental hygiene science
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• 제16권1호
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• pp.93-100
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• 2016

The purpose of this study was to compare the changes of retentive force in different stud attachment systems for implant retained overdenture. Two commercially available attachments with different retentive forces were investigated: Kerator (pink, blue, red) and O-ring (orange, red). Two implant fixtures were vertically embedded in base mountings. Five pairs of each attachment were evaluated. A universal testing machine was used to evaluate the retentive force of two attachments during wear simulation. Surface characteristics of each attachment system were evaluated with scanning electron microscopy. Five pairs of each attachment were evaluated. Kerator pink showed the highest initial retention. After 2,500 cycles of wear-simulation, Kerator pink noted the largest decrease in retention. According to results of surface analysis, Worn surfaces were obtained in matrices and patrices. Heavy wears were observed in matrices. After 2 year-wear simulation, most attachments exhibited retention loss. Attachments using different kind of material exhibited dissimilar surface alterations.

• Journal of the korean academy of Pediatric Dentistry
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• 제28권4호
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• pp.626-632
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• 2001

Ectodermal dysplasia is a hereditary disease characterized by congenital dysplasia of one or more ectodermal structures. Intraorally, common findings are anodontia or oligodontia, conical teeth, and, consequently, generalized spacing. This case presented the oral rehabilitation of a child with hypohidrotic ectodermal dysplasia. Oral rehabilitation is important from functional, esthetic, and psychologic perspectives. Due to the absence of teeth, the volume of alveolar bone and its growth are decreased, resulting in a loss of vertical dimension and protuberant lips. The treatment involved increasing the patient's vertical dimension of occlusion, fabricating a maxillary partial denture, and using magnets to help retain the mandibular partial denture. A 5-year 7-month old Korean boy was referred to the pediatric department for examination, evaluation and treatment of his disorder. we used magnets on '73 and '83 for enhanced retention of a mandibular overdenture. The magnet used in this case was the Magfit system(GC Co., Japan).

• The Journal of Korean Academy of Prosthodontics
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• 제57권2호
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• pp.189-194
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• 2019

It is necessary to set the correct occlusal plane and to distribute the occlusal force uniformly considering the state of the opposing dentition during the prosthetic of the single edentulous patient with severe alveolar bone resorption. Implant supported overdenture is superior to complete denture in terms of maintenance and stability, and limited implants are used in fully edentulous patients with high alveolar bone resorption. Telescopic attachments using a newly introduced material based on poly-aryl-ether-ketone (PAEK) have the advantages of typical telescopic copping, excellent abrasion resistance, and are lighter and more economical than conventional implant overdentures. In this case, we restored maxillary arch with a implant retained overdenture using the telescopic attachment made of Pekktonand the mandible was restored with fixed implant prosthesis. Through these procedures esthetic aspects and functional outcomes were satisfactorily achieved.

• Journal of Periodontal and Implant Science
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• 제43권1호
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• pp.12-17
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• 2013

The purpose of this review is to examine the performance of attachments used in implant-supported overdenture (IOD) in both clinical and in vitro settings and report the compiled findings, comparisons, and trends in the research literature. Articles published in PubMed on IOD attachment systems and performance were reviewed. Non-original articles were excluded. For each article included, the type of study, number of implants, number of attachment systems, and study outcome were recorded. Of the 283 articles found, 158 met the inclusion criteria. Ninety-four articles were clinical studies and 64 articles were in vitro studies. Studies on retention were the most common for in vitro studies, and four or more attachment systems were compared in most articles with significant differences in outcome. A clinical outcome of one attachment system was most common for clinical studies, while most studies had neutral outcomes overall. Ball attachment was the most commonly tested IOD attachment system. The trend in the literature showed that there is a large discrepancy between the study designs and outcomes between the clinical and the in vitro studies for IOD. Further clinical studies that can validate in vitro research should be encouraged to address this discrepancy between the two areas.

• The Journal of Korean Academy of Prosthodontics
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• 제55권3호
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• pp.292-299
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• 2017

Long-term alveolar bone resorption in edentulous patient causes difficulty in denture use. Applying an implant overdenture with 2 to 4 implants to edentulous patient is easily approachable. Moreover, it improves denture stability, support, and retention. Milled bar, the attachment used in implant overdenture, can be used to induce better stability and retention to the supporting structure than conventional bar. It has become convenient to use due to the development of CAD/CAM system which had allowed the simplification of dental techniques. In this case, application of conventional maxillary full denture and mandibular overdenture made of CAD/CAM milled bar with 4 implants showed satisfactory results in the patient who had used upper and lower full dentures for a long time.

• The Journal of Advanced Prosthodontics
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• 제4권2호
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• pp.116-120
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• 2012

Various options have been introduced for the selection of implant overdenture attachments. Attachment wear due to the repeated insertion and removal of dentures has caused problems such as decreased retention and the requirement for suprastructure remanufacturing. In these cases, a Locator bar system was applied using the drill and tapping technique to achieve total retrievability. In a 55-year-old female patient who showed three degrees of mobility in most of her teeth due to severe alveolar bone loss, a complete denture in the maxilla and an implant supported type overdenture in the mandible were planned after extracting all the remaining teeth. Six implants were placed from canine region to the distal molar region, and the locator was connected to the milled bar using the drill and tapping technique. For a 61-year-old female edentulous patient who complained of poor retention with old denture, a complete denture in the maxilla and an implant-tissue supported type overdenture in the mandible were planned. Four implants were placed in front of mental foramen, and the Locator was also connected to the Hader bar using the drill and tapping technique. With this technique, female parts can be easily replaced, and retention can be continuously maintained.

• The Journal of Korean Academy of Prosthodontics
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• 제46권4호
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• pp.359-371
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• 2008

Purpose: The purpose of this study was to investigate the stress distribution in mandibular implant overdentures with telescopic crowns compared to bar attachment. Material and methods: Three-dimensional finite element models consisting of the mandibular bone, 4 implants, and primary bar-splinted superstructure or secondary splinted superstructure with telescopic crowns were created. Vertical and oblique loads were directed onto the occlusal areas of the superstructures to simulate the maximal intercuspal contacts and working contacts such as group function occlusion. Maximum stress and stress distribution were analysed in mandibular bone, implant abutments, and superstructures. Results: 1. In comparison of von Mises stress on mandibular bone, telescopic overdenture had a little lower stress values in vertical load and working side load except oblique load. In the mandible, the telescopic overdenture distributed more uniform stress than the bar overdenture. 2. In comparison of von Mises stress on implant abutments, telescopic overdenture had much lower stress values in all load conditions. In implant abutments, the telescopic overdenture distributed stress similar to the bar overdenture. Stress was concentrated on the distal surfaces of the posterior implant abutments in both mandibular overdentures. 3. In comparison of von Mises stress on superstructures, the telescopic overdenture had much more stress values in all load conditions. However, the telescopic overdenture distributed more uniform stress on superstructure than the bar overdenture. In the bar overdenture, stress was concentrated on each cental area of bar structures and connected area between implant abutments and bar structures. Conclusion: In the results of this study, the telescopic overdenture had lower stress values than the bar overdenture in mandibular bone and implant abutments, but more stress values in superstructures. However, if optimal material was selected in making superstructures, the telescopic overdenture was compared to the bar overdenture in stress distribution.