• 한국안전학회지
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• 제14권4호
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• pp.126-134
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• 1999

In this study, plasma source ion implantation was used to improve the wear properties of biocompatible titanium implant. In order to observe the effect of ion energy and dose on wear property of titanium implant, pin-on-disk type wear tests in Hank's solution were carried out. The friction coefficient of ion implanted specimens were increased from 0.47 to 0.65 under high energy and ion dose conditions. As increasing ion energy and ion dose, the amount of wear was reduced.

• 대한통합의학회지
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• 제2권2호
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• pp.41-47
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• 2014

Purpose : The aim was to compare the implant success rate according to membrane type through a clinical case of patients, who used bio-resorbable membrane and non-resorbable membrane. Methods : A survey was conducted targeting patients with the use of bio-resorbable membrane and non-resorbable membrane who visited H dental clinic in Busan for implant surgery and bone graft for 1 year from May 2010 to May 2011. A chart was made and surveyed for 100 people with non-resorbable membrane and for 75 people with bio-resorbable membrane. Results were compared. Results : 1. As for the measurement value of Periotest M${(R)}$, the value of -8~0 was measured with 92% in case of surgery by using non-resorbable membrane. The value of +1~+9 was measured with 8.0%. In case of surgery by using bio-resorbable membrane, Peiotest M(R) was measured with 78.7% as for the value of -8~0 and 16(21.3%) as for the value of +1~+9. In light of this, a case of using non-resorbable membrane was indicated to be higher(p=0.021) in success rate than a case of using bio-resorbable membrane. 2. As a result of periodontal conditions, namely, bleeding(p=0.914), swelling(p=0.500), inflammation(p=0.074), pain(p=0.571), and itch appearance(p=0.475) according to membrane type, all were insignificant. Conclusions : A case of using non-resorbable membrane is considered to be likely to be more effective than using bio-resorbable membrane during GBR(Guided Bone Regeneration) with the use of membrane in implant surgery.

• The Journal of Advanced Prosthodontics
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• 제5권1호
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• pp.51-57
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• 2013

PURPOSE. The purpose of this study was to to analyze the effect of Type 2 diabetes on tooth mortality, implant treatment and prosthetic status. MATERIALS AND METHODS. 275 Type 2 diabetics and 300 non-diabetics, aged 40-80 years were selected for analysis. The assessment of number of teeth, missing teeth, fixed prostheses (bridge pontics), implants using panoramic radiographs and dental records were carried out. RESULTS. Diabetes mellitus (DM) patients had a higher number of missing teeth (P<.05) and placed implants (P=.074), age (P<.05), male gender percentage (P=.042), smoker percentage (P<.05) than non-DM patients. In univariate analysis, the patients in older group showed significantly higher number of tooth loss rate at the first dental examination than the patients in younger group. Tooth loss rate of smokers did not show higher value than that of non-smokers. When multiple variables including DM, age, smoking, gender were considered together, diabetics and older group patients showed significantly higher tooth loss rate at the first dental examination than non-diabetics and younger group patients, respectively. Smokers and male group did not show a significant difference than nonsmokers and female group, respectively. CONCLUSION. Tooth mortality and implant treatment rate were significantly higher in the DM group as indicated by univariate and multivariate logistic regression analysis. Old age groups showed significantly higher odds ratios and tooth loss rate. As diabetics showed the higher tooth loss rate than non-diabetics, diabetics also had more implant restorations than non-diabetics.

• 대한치과보철학회지
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• 제57권4호
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• pp.364-373
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• 2019

2급 악간관계를 갖는 환자는 1급 악간관계인 환자와는 달리 불안정한 교합을 가질 수 있으며, 무치악인 경우 총의치를 사용할 때 불안정한 교합을 보이면서 의치의 움직임이 커질 가능성이 있다. 이런 환자에 있어 임플란트 피개의치를 사용함으로써 의치의 안정을 향상시킬 수 있다. 임플란트 피개의 치에서 attachment 종류는 크게 bar type과 solitary type으로 나눌 수 있는데 각각 적응증이 있어 상황에 따라 적용을 달리 하여야 한다. 본 증례는 2급 악간관계를 가진 하악 무치악 환자에서 임플란트 피개의치를 계획함에 있어 디지털 기술을 이용함으로써 더 적합한 attachment를 선택하고 임플란트의 위치 및 깊이를 미리 계획하여 계획한 위치에 식립하였다. 상악은 국소의치로 수복하였고 하악은 임플란트 피개의치로 수복하여 만족할만한 결과를 얻었기에 이를 보고하고자 한다.

• 대한치과보철학회지
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• 제44권5호
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• pp.584-593
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• 2006

Statement of problem : Dental implant which has been developed gradually through many experiments and clinical applications is presently used to various dental prosthetic treatments. To conduct a successful function of implant prosthesis in oral cavity for a long time, it is important that not only structure materials must have the biocompatibility, but also the prosthesis must be designed for the stress, which is occurred in occlusion, to scatter adequately of load support. Therefore, it is essential to give the consideration about the stress analysis of supporting tissues for higher successful rates. Purpose : Recently, many implant manufacturing company produce various taper design of root form implant, the fixture is often selected. However, the stress analysis of taper form fixture still requires more studies. Material and method : This study we make the element models that five implant fixture; Branemark system(Nobel Biocare, Gothenberg, Sweden), Camlog system(Altatec, Germany), Astra system(Astra Tech, Sweden), 3i system(Implant Innovations Inc, USA), Avana system(Osstem, Korea) were placed in the area of mandibular first premolar and prosthesis fabricated, which we compared with stress distribution using the three-dimension finite element analysis under two loading condition. Results : This study compares the aspect of stress distribution of each system with the standard of Von mises stress, among many resulted from finite element analysis so that this research gets the following results. 1. In all implant system, oblique loading of maximum Von mises stress of implant, alveolar bone and crown is higher than vertical loading of those. 2. Regardless of loading conditions and type of system, cortical bone which contacts with implant fixture top area has high stress, and cancellous bone has a little stress. under the vertical loading, maximum Von mises stress is more higher in order of Branemark, Camlog, Astra, 3i, Avana. under the horizontal loading, maximum Von mises is more higher in order of Camlog, Branemark, Astra, 3i, Avana.

• 대한치과보철학회지
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• 제44권4호
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• pp.414-420
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• 2006

Purpose : The purpose of this study is to use finite element analysis to predict the fatigue life of an implant system subjected to fatigue load by mastication (chewing force). The reliability and the stability of implant system can be defined in terms of the fatigue strength. Not only an implant is expensive but also it is almost impossible to correct after it is inserted. From a bio-engineering standpoint, the fatigue strength of the dental implant system must be evaluated by simulation (FEA). Material and Methods Finite element analysis and fatigue test are performed to estimate the fatigue strength of the implant system. Mesh of implant is generated with the actual shape and size. In this paper, the fatigue strength of implant system is estimated. U-fit (T. Strong, Korea, internal type). The stress field in implant is calculated by elastic-plastic finite element analysis. The equivalent fatigue stress, considering the contact and preload stretching of a screw by torque for tightening an abutment, is obtained by means of Sine's method. To evaluate the reliability of the calculated fatigue strength, fatigue test is performed. Results: A comparison of the calculated fatigue strength with experimental data showed the validity and accuracy of the proposed method. The initiation points of the fatigue failure in the implant system exist in the region of high equivalent fatigue stress values. Conclusion: The above proposed method for fatigue life estimation tan be applied to other configurations of the differently designed and improved implant. In order to prove reliability of prototype implant, fatigue test should be executed. The proposed method is economical for the prediction of fatigue life because fatigue testing, which is time consuming and precision-dependent, is not required.

• The Journal of Advanced Prosthodontics
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• 제11권6호
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• pp.341-349
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• 2019

PURPOSE. A novel retentive type of implant prosthesis that does not require the use of cement or screw holes has been introduced; however, there are few reports examining the biomechanical aspects of this novel implant. This study aimed to evaluate the biomechanical features of cementless fixation (CLF) implant prostheses. MATERIALS AND METHODS. The test groups of three variations of CLF implant prostheses and a control group of conventional cement-retained (CR) prosthesis were designed three-dimensionally for finite element analysis. The test groups were divided according to the abutment shape and the relining strategy on the inner surface of the implant crown as follows; resin-air hole-full (RAF), resin-air hole (RA), and resin-no air hole (RNA). The von Mises stress and principal stress were used to evaluate the stress values and distributions of the implant components. Contact open values were calculated to analyze the gap formation of the contact surfaces at the abutment-resin and abutment-implant interfaces. The micro-strain values were evaluated for the surrounding bone. RESULTS. Values reflecting the maximum stress on the abutment were as follows (in MPa): RAF, 25.6; RA, 23.4; RNA, 20.0; and CR, 15.8. The value of gap formation was measured from 0.88 to 1.19 ㎛ at the abutment-resin interface and 24.4 to 24.7 ㎛ at the abutment-implant interface. The strain distribution was similar in all cases. CONCLUSION. CLF had no disadvantages in terms of the biomechanical features compared with conventional CR implant prosthesis and could be successfully applied for implant prosthesis.

• The Journal of Advanced Prosthodontics
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• 제4권4호
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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.

• Journal of Periodontal and Implant Science
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• 제53권3호
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• pp.194-206
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• 2023

Purpose: A novel attachment system for implant-retained overdentures (IRODs) with novel material combinations for improved mechanical resilience and prosthodontic success (Novaloc) has been recently introduced as an alternative to an existing system (Locator). This study investigated whether differences between the Novaloc and Locator attachment systems translate into differences in implant survival, implant success, and patient-centered outcomes when applied in a real-world in-practice comparative setting in patients restored with mandibular IRODs supported by 2 interforaminal implants (2-IRODs). Methods: This prospective, intra-subject crossover comparison compared 20 patients who received 2 intra-foraminal bone level tapered implants restored with full acrylic overdentures using either the Locator or Novaloc attachment system. After 6 months of function, the attachment in the corresponding dentures was switched, and the definitive attachment system type was delivered based on the patient's preference after 12 months. For the definitive attachment system, implant survival was evaluated after 24 months. The primary outcomes of this study were oral health-related quality of life and patient preferences related to prosthetic and implant survival. Secondary outcomes included implant survival rate and success, prosthetic survival, perceived general health, and patient satisfaction. Results: Patient-centered outcomes and patient preferences between attachment systems were comparable, with relatively high overall patient satisfaction levels for both attachment systems. No difference in the prosthetic survival rate between study groups was detected. The implant survival rate over the follow-up period after 24 months in both groups was 100%. Conclusions: The results of this in-practice comparison indicate that both attachment systems represent comparable candidates for the prosthodontic retention of 2-IRODs. Both systems showed high rates of patient satisfaction and implant survival. The influence of material combinations of the retentive system on treatment outcomes between the tested systems remains inconclusive and requires further investigations.

• 구강회복응용과학지
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• 제19권2호
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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.