• 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.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.327-353
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• 1994

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.283-290
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• 2011

Purpose: This study compared the marginal bone loss around dental implant that were placed in the canine areas of the mandibles and finded the survival rate of implants, marginal bone loss around implants and prosthetic complications in 10 patients treated with overdentures retained with Locator attachments. Materials and methods: Ten patients who had received implant retained overdentures in the mandibules using two implants and Locator attachments at Daegu Catholic University Medical Center from 2004 to 2010 were included in this study. Evaluations of the survival rate of implants, marginal bone loss and prosthetic complications were performed. Results: Implants placed in this study showed a 100% survival rate and the average annual bone loss was 1.03 mm ${\pm}$ 0.20 mm in the first year. The patients have verbally indicated that they are comfortable and that their overdentures function well. But, implant retained overdentures had various prosthetic complications such as male change, relining, rebasing and denture fracture. Conclusion: Implant retained overdentures using two implant and Locator attachments in the fully edentulous mandibles is considered as a stable way for long terms because of minimal invasive operation, simple prosthetic process and easy repair.

• Journal of Yeungnam Medical Science
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• v.39 no.4
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• pp.341-343
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• 2022

To determine the vertical dimension and centric relation during the construction of implant overdentures, the record base and wax rim may need to be adjusted. The conventional method has several drawbacks, as it requires repeated tightening and loosening of the impression coping. Here, we report a useful and novel method for interocclusal records using the healing abutments in implant overdentures. Our case demonstrates that this method is easier and simpler and prevents gingival collapse.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.3
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• pp.311-318
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• 2017

Several types of attachments have been used for implant supported and/or retained overdentures. Locator is one of the stud type attachments and it has been generally used. However, the colored matrix is resilient and vulnerable to wear, so frequent post-insertion maintenance is needed. To solve this problem, it is necessary to introduce innovative attachment system. Overdentures using Air Gap attachment (AGA) has improved masticatory function and facial esthetics. AGA is made of metal, so it could be more resistant to wear or friction than the other resilient attachments. Nevertheless, AGA plays a role in stress breakers because it allows movement during denture movement with predetermined gap. In addition, both pre-existing implants and natural teeth were successfully used for connection of AGA. AGA could replace other unsplinted type of attachments. Overdentures using AGA could provide satisfactory result in terms of function, esthetics and retention. However, long term follow up is needed.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.6
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• pp.760-768
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• 2007

Statement of problem. Conventional denture treatment for totally edentulous patients is associated with a variety of functional and psychosocial problems. The placement of implants in the anterior region of the maxilla and mandible and the fabrication of an implant-retained overdenture might solve these problems. Purpose. This study compared the marginal bone loss around the implant and evaluated the implant survival rate and complications in patients treated with overdentures retained by implants for 2 years. Material and methods. Patients who had received implant-retained overdentures using a Dolder bar at Samsung Medical Center from January 1999 to June 2005 and had participated in the annual recall programs for two years were selected for this study. A total of 18 patients and 56 $Br{\aa}ne-mark\;system^{(R)}$ implants were used, and their data were reviewed. Evaluations of the survival rate, bone quality, marginal bone loss, and complications were performed. The data on the Dolder bar length and clip length were measured. The change in marginal bone loss and the correlation between the marginal bone loss and bar length, clip length, or bone quality were investigated. Results. Implants placed in this study showed a 100% survival rate. The average annual bone loss was 1.12mm in the first year and 0.27mm in the second year in the maxilla, and 0.58mm in the first year and 0.22mm in the second year in the mandible. The marginal bone loss in the maxilla showed no significant association with those in the mandible. (P>.05). There was no significant difference in marginal bone loss around implants between the first and second year. (P>.05) There was no statistically significant relationship (P>.05) between the marginal bone loss and bone quality, clip length, or Dolder bar length. The Dolder bar length showed a high correlation with the clip length. (P<.05) Various complications were noted. Conclusion. These results confirmed the favorable outcome for patients treated with implant-retained overdentures.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.2
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• pp.153-162
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• 2013

This study compared the marginal bone loss around dental implants that were placed in the canine areas of the mandibles and finded the survival rate of the implants, marginal bone loss around implants and prosthetic complications in 20 patients treated with overdentures retained with Locator attachments. Implants placed in this study showed a 95% survival rate and the average marginal bone loss was 1.21 mm($SD{\pm}0.60mm$) in 94.3 weeks of functional loading. Implant-retained overdentures had various prosthetic complications such as male change, metal cap loosening, Locator attachment loosening, denture teeth change, relining and denture fracture. Implant-retained overdentures using two implants and Locator attachments in the edentulous mandibles is considered as a stable way for long terms because of minimal invasive operation, simple prosthetic process and easy repair.

• The Journal of Advanced Prosthodontics
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• v.4 no.4
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• pp.204-209
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• 2012

PURPOSE. The aim of this systematic review is to address treatment outcomes of Mandibular implant overdentures relative to implant survival rate, maintenance and complications, and patient satisfaction. MATERIALS AND METHODS. A systematic literature search was conducted by a PubMed search strategy and hand-searching of relevant journals from included studies. Randomized Clinical Trials (RCT) and comparative clinical trial studies on mandibular implant overdentures until August, 2010 were selected. Eleven studies from 1098 studies were finally selected and data were analyzed relative to number of implants. RESULTS. Six studies presented the data of the implant survival rate which ranged from 95% to 100% for 2 and 4 implant group and from 81.8% to 96.1% for 1 and 2 implant group. One study, which statistically compared implant survival rate showed no significant differences relative to the number of implants. The most common type of prosthetic maintenance and complications were replacement or reattaching of loose clips for 2 and 4 implant group, and denture repair due to the fracture around an implant for 1 and 2 implant groups. Most studies showed no significant differences in the rate of prosthetic maintenance and complication, and patient satisfaction regardless the number of implants. CONCLUSION. The implant survival rate of mandibular overdentures is high regardless of the number of implants. Denture maintenance is likely not inflenced substantially by the number of implants and patient satisfaction is typically high again regardless os the number of implants.

• The Journal of Advanced Prosthodontics
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• v.4 no.4
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• pp.197-203
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• 2012

PURPOSE. The aim of this systematic review was to address treatment outcome according to attachment systems for mandibular implant overdentures in terms of implant survival rate, prosthetic maintenance and complications, and patient satisfaction. MATERIALS AND METHODS. A systematic literature search was conducted using PubMed and hand searching of relevant journals considering inclusion and exclusion criteria. Clinical trial studies on mandibular implant overdentures until August, 2010 were selected if more than one type of overdenture attachment was reported. Twenty four studies from 1098 studies were finally included and the data on implant survival rate, prosthetic maintenance and complications, patient satisfaction were analyzed relative to attachment systems. RESULTS. Four studies presented implant survival rates (95.8 - 97.5% for bar, 96.2 - 100% for ball, 91.7% for magnet) according to attachment system. Ten other studies presented an implant survival rate ranging from 93.3% to 100% without respect to the attachment groups. Common prosthetic maintenance and complications were replacement of an assay for magnet attachments, and activation of a matrix or clip for ball or bar attachments. Prosthetic maintenance and complications most commonly occurred in the magnet groups. Conflicting findings were found on the rate of prosthetic maintenance and complications comparing ball and bar attachments. Most studies showed no significant differences in patient satisfaction depending upon attachment systems. CONCLUSION. The implant survival rate of mandibular overdentures seemed to be high regardless attachment systems. The prosthetic maintenance and complications may be influenced by attachment systems. However patient satisfaction may be independent of the attachment system.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.49-57
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• 1991

The magnets were widely used to increase the retention of overdentures. The purpose of this study was to compare the break load between overdentures and edentulous models. For this study, Model former(U-402) was used for model fabrication and four different magnets were used for evaluation of break load. The artificial saliva was used between overdenture and model. Breakaway loads were tested with an Instron 1122 at a speed of 2mm/min. The results were as follows. 1. The retentivee forces complete dentures with artificial saliva were than the retentive forces of complete detures without artificial saliva. 2. Magnetic overdenture with artificial saliva showed best retentive force, magnetic overdenture without artificial saliva showed the next retentive force, and the complete denture without artificial saliva showed the worst retention. 3. As the magnetic sizes increased, the retentive forces of magnetics were increased. 4. The retentive force of nipple shape magnet is greater than the retentive force of flate shape magnet in the same size.