• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.85-93
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• 2016

PURPOSE. The purpose of this study was to determine the effect of anchorage systems and palatal coverage of denture base on load transfer in maxillary implant-retained overdenture. MATERIALS AND METHODS. Maxillary implant-retained overdentures with 4 implants placed in the anterior region of edentulous maxilla were converted into a 3-D numerical model, and stress distribution patterns in implant supporting bone in the case of unilateral vertical loading on maxillary right first molar were compared with each other depending on various types of anchorage system and palatal coverage extent of denture base using three-dimensional finite element analysis. RESULTS. In all experimental models, the highest stress was concentrated on the most distal implant and implant supporting bone on loaded side. The stress at the most distal implant-supporting bone was concentrated on the cortical bone. In all anchorage system without palatal coverage of denture base, higher stresses were concentrated on the most distal implant and implant supporting bone on loaded side. CONCLUSION. It could be suggested that when making maxillary implant retained overdenture, using Hader bar instead of milled bar and full palatal coverage rather than partial palatal coverage are more beneficial in distributing the stress that is applied on implant supporting bone.

• The Journal of the Korean dental association
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• v.55 no.7
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• pp.457-466
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• 2017

In the case of failed fixed implant prosthesis accompanied by abutment screw fracture, fractured screw fragment must be removed to use the existing implant fixtures. A 61-year-old male patient, who had a failed maxillary fixed implant prosthesis accompanied by three abutment screw fracture, hoped to reconstruct the maxillary implant prosthesis, while maintaining the existing implant fixtures. To use the existing implant fixtures, fractured screw fragments were removed. A maxillary implant overdenture using available existing implants was planned. Bar-attachment with Locator was used for implant splinting, denture stability, and retention. Final impression was taken after treatment of peri-implantitis. Jaw relation registration was taken to evaluate available interarch space for bar-attachment. After fabricating bar-attachment, centric relation was taken. Implant overdenture using bar-attachment with Locator was delivered after wax-denture evaluation. This case report showed that a satisfactory clinical result was achieved by implant overdenture using existing implant fixtures in a maxillary edentulous patient.

• The Journal of Advanced Prosthodontics
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• v.6 no.4
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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.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.4
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• pp.321-328
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• 2017

Treatment options for edentulous patients are complete denture and implant prosthesis. A two implant-retained overdenture can be considered the first treatment in the edentulous mandible, but there is no clear consensus of treatment for edentulous maxilla. Implant-retention/support overdenture shows better retention and stability than complete denture and is less expensive and more esthetic than implant-supported fixed prosthesis. CM $LOC^{(R)}$ $Pekkton^{(R)}$ attachment is a solitary type attachment and evaluated to have excellent abrasion resistance and retention with a female part made of poly-ether-ketone-ketone. Meanwhile, SR Ivocap system is injection molding method and discussed to show few changes in the vertical dimension of denture and have excellent fracture resistance. In this case, we restored maxillary arch with a four implant-retained overdenture using CM $LOC^{(R)}$ $Pekkton^{(R)}$ and SR Ivocap system, and mandibular arch with a removable partial denture. Through this procedure, satisfactory outcomes were achieved both in functional and esthetic aspects.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.1
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• pp.64-70
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• 2014

The purpose of this case report is to introduce milled titanium bar with Locator$^{(R)}$ that made by CAD/CAM for implant supported overdenture in maxillary edentulous patients. For over 2 years, in terms of function and esthetics, satisfactory result was obtained.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.193-200
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• 2008

Statement of problem: There have been a few studies about unsplinted implant retainted maxillary overdenture. Purpose: The purpose of this study was to examine the effect of different position of implant for 2 implants-retained maxillary overdenture. Materials and methods: Three-dimensional finite element models were used to reproduce an edentulous human maxilla with an implant-retained overdenture. Two implants in the canine tooth positions on both side and in the second premolar tooth positions on both side models were examined. Axial loads of 100 N were applied to the occlusal surface at the right first molar tooth positions. Maximum stress at the implant-bone interface and stress at the cortical bone surface just under the loading point were observed. Results and conclusion: Within the limits of this study, maximum stresses were concentrated around implant of canine position at loading side. The second premolar area was thought to be more favorable to distribution of stress on mucosa, alveolar bone and implants than canine area for maxillary overdenture.

• 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.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.4
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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 Korean Academy of Prosthodontics
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• v.42 no.4
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• pp.397-411
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• 2004

Purpose: The purpose of this study was to determine the effect of anchorage systems and palatal coverage of denture base on load transfer in maxillary implant-supported overdenture. Material and methods: Maxillary implant -supported overdentures in which 4 implants were placed in the anterior region of edentulous maxilla were fabricated, and stress distribution patterns in implant supporting bone in the case of unilateral vertical loading on maxillary right first molar were compared with each other depending on various types of anchorage system and palatal coverage extent of denture base using three-dimensional photoelastic stress analysis. Two photoelastic overdenture models were fabricated in each anchorage system to compare with the palatal coverage extent of denture base, as a result we got eight models : Hader bar using clips(type 1), cantilevered Hader bar using clips(type 2), Hader bar using clip and ERA attachments(type 3), cantilevered milled-bar using swivel-latchs and frictional pins(type 4). Result: 1. In all experimental models, the highest stress was concentrated on the most distal implant supporting bone on loaded side. 2. In every experimental models with or without palatal coverage of denture base, maximum fringe orders on the distal ipsilateral implant supporting bone in an ascending order is as follows; type 3, type 1, type 4, and type 2. 3. Each implants showed compressive stresses in all experimental models with palatal coverage of denture base, but in the case of those without palatal coverage of denture base, tensile stresses were observed in the distal contralateral implant supporting bone. 4. In all anchorage system without palatal coverage of denture base, higher stresses were concentrated on the most distal implant supporting bone on loaded side. 5. The type of anchorage system affected in load transfer more than palatal coverage extent of the denture base. Conclusion: To the results mentioned above, in the case of patients with unfavorable biomechanical conditions such as not sufficient number of supporting implants, short length of the implant, and poor bone quality, selecting a resilient type attachment or minimizing the distal cantilevered bar is considered to be an appropriate method to prevent overloading on implants by reducing cantilever effect and gaining more support from the distal residual ridge.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.2
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• pp.176-183
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• 2014

Severely absorbed edentulous ridge cannot bear mechanical stress, causes undesired transformation of oral environment and makes patients difficult to adapt to dentures. Nowadays implant overdenture can be a treatment of choice in order to relieve patients' discomfort and improve stability and retention of the denture. Placement of implant on maxilla is difficult because of its bone quality and anatomic structure. It also has wide supportive tissue and convenience of border sealing, which provides sufficient support and stabilization with conventional complete denture. Mandible, on the other hand, is difficult to obtain sufficient support, retention and stabilization with conventional complete denture. Therefore, implant overdenture is recommended on mandible. Locator attachment has been improved for convenience of use and male parts of various retention enabled it to replace ball type attachment clinically. In this study, we restored maxillary arch with conventional denture, and mandibular arch with implant and tissue-supported overdenture and Locator attachment system.