• 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 Periodontal and Implant Science
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• v.44 no.3
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• pp.102-108
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• 2014

Purpose: Rehabilitation of the incomplete dentition by means of osseointegrated dental implants represents a highly predictable and widespread therapy; however, little is known about potential risk factors that may impair long-term implant success. Methods: From 2004 to 2012, a total of 13,147 implants were placed in 4,316 patients at the Academy for Oral Implantology in Vienna. The survival rates after 8 years of follow-up were computed using the Kaplan-Meier method, and the impact of patient- and implant-related risk factors was assessed. Results: Overall implant survival was 97% and was not associated with implant length (P=0.930), implant diameter (P=0.704), jaw location (P=0.545), implant position (P=0.450), local bone quality (P=0.398), previous bone augmentation surgery (P=0.617), or patient-related factors including osteoporosis (P=0.661), age (P=0.575), or diabetes mellitus (P=0.928). However, smoking increased the risk of implant failure by 3 folds (P<0.001) and a positive history of periodontal disease doubled the failure risk (P=0.001). Conclusions: Summing up the long-term results of well over 10,000 implants at the Academy for Oral Implantology in Vienna it can be concluded that there is only a limited number of patients that do not qualify for implant therapy and may thus not benefit from improved quality of life associated with fixed implant-retained prostheses.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.611-620
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• 2008

Purpose: The purpose of this study was to assess the long term survival rates of the most posterior single tooth implant and to evaluate the influence of implant characteristics on implant survival. Material and Methods: This retrospective report presents findings on 37 patients with 43 implants replacing single molars. The inclusion criteria were having implants replacing a molar of the most posterior region and follow-up data over at least 6 months. Data were recorded regarding the incidence of complications and survival rates of these implants. Results: The range of follow-up was from 9 to 66 months(mean: 40.2 months). The cumulative survival rate of total implants was 93.0% which reflects the loss of three implants: one had broken neck, one implant failed because of infection, one implant showed failed osseointegration. Abutment- screws loosening occurred in five implants(11.6%). Conclusion: Within the limits of this study, a single tooth-implant can serve as a good long-term and predictable treatment modality to replace the most posterior teeth with low complication and failure rates.

• The Journal of the Korean dental association
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• v.51 no.5
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• pp.242-249
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• 2013

The proper occlusal design is one of the most important factors for the long-term success. The purpose of this research is to investigate and define occlusal considerations to reduce failure of implant-supported fixed prostheses. The physiological movement of implants is markedly lower than that of natural teeth and they also lack in occlusal sensitivity. Proper occulsal 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 can be assured by reducing early occulsal loading to avoid implant overloading and selecting appropriate occlusion material.

• The Journal of the Korean dental association
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• v.56 no.11
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• pp.616-621
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• 2018

This clinical case highlights the failure of long length implants, and the prosthodontic procedures necessary to rehabilitate the maxillary dentition of a patient with microstomia. The integrated digital technology of intra-oral scanning, computer-aided design, and three-dimensional printing can provide an alternative method to make conventional impressions for patients with microstomia who cannot insert the appropriate tray in their mouths.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.6
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• pp.625-632
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• 2001

Statement of Problem. Objective and quantitative measurement of implant stability is very important from implant installation to long-lasting maintenance period thereafter. Purpose of study. This study was to evaluate and compare two ISQ and PTVs on the implant stability measurements according to the increased effective implant length. Materials and methods. Twenty self-tapping fixtures were installed in the bovine scapula and in 10 of those for group I, ISQ and PTVs were obtained in the vertical/horizontal directions according to the increased effective implant length using $Osstell^{TM}$ and $Periotest^{(R)}$. After stability measurement, removal torques were measured between the after installation and after thread exposure group. Results. ISQ and PTVs showed decreased and increased values according to the increased abutment length. Apart from PTVs, ISQ values were shown higher in horizontal direction to the long axis of bone in both the after installation and the after thread exposure groups. Removal torque values were shown higher in after installation group. Conclusion. From the results of this study, implant stability measurement using resonance frequency analysis was more sensitive and discriminative than PTVs measurement.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.4
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• pp.627-646
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• 1997

In order to find the degree of osseointegration at bone-implant interface of clinically successful implants, models including the 3.75mm wide, 10mm long screw type $Br{\aa}nemark$ implant as a standard and cylinder, 15mm long, 5.0mm wide, two splinted implants, and implants installed in various cancellous bone density were designed. Also, the amount of load and material of prostheses were changed. The stress and minimum contact fraction were analyzed on each model using three-dimensional finite element method(I-DEAS and ABAQUS version 5.5). The results of this study were as follows. 1. 10mm long, 3.75mm diameter-screw type implant had $36.5{\sim}43.7%$ of minimum contact fraction. 2. Cylinder type implant showed inferior stress distribution and higher minimum contact fraction than screw type. 3. As implant length was increased, minimum contact fraction was increased a little, however, maximum principal stress was decreased. 4. Implants with a large diameter had lower stress value with slightly higher minimum contact fraction than standard screw type. 5. Two splinted implants showed no change of minimum contact fraction. 6. The higher bone density, the lower stress value. 7. The material of occlusal surface had no effect on the stress of the bone-implant interface.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.34.1-34.14
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• 2015

Background: Over the past 30-40 years, various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). The aim of this study is to present the long-term clinical results of carbon/carbon implants, and the results of the scanning electron microscope and energy dispersive spectrometer investigation of an implant retrieved from the human body after 8 years. Methods: Mandibular reconstruction (8-10 years ago) was performed with pure (99.99 %) carbon implants in 16 patients (10 malignant tumours, 4 large cystic lesions and 2 augmentative processes). The long-term effect of the human body on the carbon/carbon implant was investigated by comparing the structure, the surface morphology and the composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Results: Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. During the long-term follow-up, plate fracture, loosening of the screws, infection or inflammations around the carbon/carbon implants were not observed. The thickness of the carbon fibres constituting the implants did not change during the 8-year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering implants. Conclusions: The surface morphology and the structure were not changed after 8 years. The two main components of the implant retrieved from the human body are still carbon and oxygen, but the amount of oxygen is 3-4 times higher than on the surface of the reference implant, which can be attributed to the oxidative effect of the human body, consequently in the integration and biocompatibility of the implant. The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.2
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• pp.97-109
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• 2022

Purpose: This study aims to investigate the risk indicators contributing to implant failure, and analyze the relationship between risk indicators and marginal bone loss (MBL) through long-term follow-up over 3 years. Materials and Methods: From 2003 to 2017, patients' medical charts with a history of dental implant surgery at Chonnam National University Dental Hospital were reviewed retrospectively. The patient's demographic variables, and clinical variables were recorded. Periapical radiographs were used to evaluated the changes in MBL around implants. And we analyzed implant survival rates. Multiple regression analysis with backward elimination was conducted to correlate the patient's clinical variables and implant failure and Pearson correlation analysis was performed to the correlated between implant long-term survival rates and MBL and initial stability. Results: In multiple regression analysis, there was a statistically significant negative correlation between abutment connection type (β = -.189, P < .05), with or without SPT (β = -.163, P < .05), diabetes (β = -.164, P < .05), osteoporosis (β = -.211, P < .05) and MBL. Anticoagulant medication influenced the long-term success rate of implants. PTV values at the second implant surgery showed a statistically significant negative correlation with long-term implant survival (P < .05). Conclusion: For the long-term success of the implant, the appropriate abutment connection type must be selected and the periodic SPT is recommended. Systemic diseases such as diabetes and osteoporosis and anticoagulant medication should be considered. Furthermore, since high PTV at the second implant surgery correlated with the long-term survival rates of the implant, initial stability should be carefully considered before undergoing the prosthetic procedure.

• The Journal of Advanced Prosthodontics
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• v.4 no.4
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• pp.210-217
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• 2012

PURPOSE. The purpose of this study was to analyze the current literatures and to assess outcomes of implant treatment in patients with generalized aggressive periodontitis. MATERIALS AND METHODS. Studies considered for inclusion were searched in Pub-Med. The literature search for studies published in English between 2000 and 2012 was performed. Our findings included literature assessing implant treatment in patients with a history of generalized aggressive periodontitis (GAP). All studies were screened according to inclusion criteria. The outcome measures were survival rate of superstructures, marginal bone loss around implant and survival rate of implants. All studies were divided into two follow-up period: short term study (< 5 years) and long term study (${\geq}5$ years). RESULTS. Seven prospective studies were selected, including four short-term and three long-term studies. The survival rates of the superstructures were generally high in patients with GAP, i.e. 95.9-100%. Marginal bone loss around implant in patients with GAP as compared with implants in patients with chronic periodontitis or periodontally healthy patients was not significantly greater in short term studies but was significantly greater in long term studies. In short term studies, the survival rates of implants were between 97.4% and 100% in patients with GAP-associated tooth loss, except one study. The survival rates of implants were between 83.3% and 96% in patients with GAP in long term studies. CONCLUSION. Implant treatment in patients with GAP is not contraindicated provided that adequate infection control and an individualized maintenance program are assured.