• Journal of Periodontal and Implant Science
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• 제36권3호
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• pp.673-682
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• 2006

Recent study shows that implant design has a great impact on initial stability in bone. The ITI $TE^{(R)}$ implant, designed originally for immediate placement has a tapered/ cylindrical form which fits the anatomical shape of the natural alvelous or tooth root. The increased diameter at the collar region coupled with more threads lead to more bone contact and enhanced stability. The aim of this retrospective study is to evaluate the clinical use and the efficacy of recently introduced ITI TE implant with a new macro-design. The following results are compiled from 139 patients who received ITl TE implant surgery at the periodontal department. of Yonsei University Hospital between July 2002 and September 2005. 1. 139 patients received 173 ITl $TE^{(R)}$ implants in their maxilla and mandible (Mx 82, Mn 91). Posterior area accounted for 84% of the whole implant surgery, 2. In the distribution of bone quality, type III(41,0%) was the most, followed by type IV(41,0%) and type II (27.7%). As for the bone quantity, type B(43.9%) was the most, followed by type C(42.2%), type D(12.2%) and type A(1.7%). 3. 125 implants(83.9%) were treated by single crown, which accounted for the majority. 4, The total implant survival rate was 100% after a mean follow-up period of 21.2 months. This preliminary data with ITl $TE^{(R)}$ implant showed excellent survival rate although the majority of implants evaluated in this study were placed in the posterior region of the jaw and compromised sites.

• 대한치과보철학회지
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• 제62권2호
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• pp.146-156
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• 2024

임플란트 보조 국소의치의 치료는 오래전부터 여러 형태로 시도되어 왔으며, 이 중 임플란트 서베이드 크라운 국소의치의 경우 점차 예지성을 얻고 있으며, 특히 경제적, 해부학적으로 불리한 부분 무치악 환자에게 한 가지 치료 방법이 될 수 있다. 이때 임플란트의 식립 위치는 치료 목적에 따라 전방 식립과 후방 식립으로 분류될 수 있는데, 이는 환자의 치조제, 잔존치 예후, 대합치 등 여러 상황을 고려하여 결정되어야 한다. 본 증례에서는 하악 Kennedy 1급 부분 무치악 환자에게 두 개의 임플란트 서베이드 크라운을 활용한 하악 임플란트 보조 국소의치를 통해 수복하였다. 본 환자에게 후방 식립이 어렵다는 점과 잔존치의 예후를 고려하여 임플란트를 잔존치에 근접한 부위에 두 개를 식립하는 것이 계획되었으며, 가이드 수술을 통해 계획한 위치, 각도, 깊이에 식립되었다. 고정성 보철물 제작 과정은 상악 무치악 치아 배열 과정과 병행하여 예지성을 높였고, 국소의치를 제작 시에는 임플란트가 최후방 지대치로서 과도한 하중이 가하지 않도록 기능 운동을 허용하는 형태로 디자인되고, 이차 인상 과정을 거쳐 제작되었다. 각 치료 과정을 계획한대로 진행하여 환자와 술자 모두 심미적, 기능적으로 만족스러운 결과를 얻었기에 이를 보고하는 바이다.

• 대한치주과학회:학술대회논문집
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• 대한치주과학회 2007년도 제47회 종합학술대회 연제초록
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• pp.180-181
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• 2007

• 대한치과보철학회지
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• 제59권1호
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• pp.126-133
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• 2021

여러 연구에서 임플란트 지지 보철물의 수직 침하에 대해 보고되고 있지만, 구강내 임플란트 지지보철물의 기능 시 수직침하 양상에 대해서는 알려진 바 없다. 본 증례에서는 2명의 환자에서 구치부 단일 치아 임플란트 지지 보철물의 3차원적인 변화를 평가하였다. 내부연결형 임플란트를 식립하였으며 통상적인 방법으로 Screw-Cement Retained Prosthesis(SCRP) 형태의 보철물을 제작해 장착하였다. 구강스캐너(Cerec Omnicam, Dentsply Sirona, USA)를 이용해 보철물 장착 시, 장착 1주, 1개월, 1년 후 구강 스캔을 시행하였으며 디지털 분석 프로그램(Geomagic Control X, 3D systems, USA)을 이용해 기간에 따른 위치 변화를 3차원적으로 평가하였다. 인접 치아를 기준으로 보철물 장착 후 임상적인 위치 변화가 나타났으며 변화량은 시간이 지남에 따라 증가하였다.

• 대한치과보철학회지
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• 제36권2호
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• pp.258-272
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• 1998

This investigation evaluated patients who received Steri-Oss implants from the Dental Hospital of Chosun University during the period from March 1989 to August 1997. 346 fixtures of 127 patients were included in this study. The results were as follows ; 1.The follow-up period was defined as the period between the surgical placement of the implants and the last follow-up examination. The mean follow-up period was $2.17{\pm}1.21$ years. 2.The period between fixture installation and second surgery was $0.71{\pm}0.44$ years in the maxilla and $0.46{\pm}0.21$ years in the mandible. 3.The number of fixtures which were installed in the upper jaw(112) was less than that in the lower jaw(234) and in the posterior region(260) was more than in the anterior region(86). 4.The length of fixture which was most frequently used was 12 mm and least was 8mm. Screw implants were installed more than cylindrical implants. 3.8mm implant was the most common implans, followed by 4.5mm and 3.25mm. 5.The number of augmentation cases was more than that of non-augmentation cases and the rate of augmentation cases in the maxilla was more than that in the mandible. 6.Implant restorations for partial edentulos patients(94cases) were more than single- tooth implant restorations(33cases) or implant restorations for complete edentulos patients(10cases). 7.Free-standing prostheses for partially edentulous patients were more commom than any other type of connection between implants and natural teeth. 8.Plaque Index($0.95{\pm}0.74$) and Gingival Index($0.31{\pm}0.52$) were very similar around the natural teeth and reflected an acceptable level of plaque and gingivitis control. Mean value for keratinized mucosa index($1.93{\pm}1.20$) remained fairly constant around level 2(1-2 mm keratinized epithelium). 9.Patients were generally satisfied with implant in terms of comfort, function, speech and esthetics. 10.There was not a statistically significant differences in overall survial rate between implants placed in the maxilla (91.5%) and those placed in the mandible (93.8%). Fourteen implants lost before the prosthetic rehabilitation and eleven implants lost following variable periods in function after the prosthetic phase of the treatment. 11.Cause of implant failures was exfoliation or removal of fixture due to non-osseointegration before the prosthetic rehabilitation or due to fracture of fixture, masticatory pain after the prosthetic rehabilitation. 12.The survival rate of Steri-Oss implants using the Kaplan-Meier statistical analysis was 93.8% at 2 year and 86.6% at 5 year, In all cases, implant losses occured predominantly in the healing period. There was a steep decline in the rate of implant loss after the first year. 13.The survival rate of Steri-Oss implants in the anterior region was 94.8% at 2 year and 94.8% at 5 year and that in the posterior region was 92.8% at 2 year and 75.9% at 5 year. In conclusion, this study revealed a number of parameters and guidelines for achieving an optimal success rate in osseointegration.

• Journal of Periodontal and Implant Science
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• 제44권1호
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• pp.8-12
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• 2014

Purpose: The aim of this retrospective chart review was to evaluate the four-year survival rate of a titanium implant system. Methods: A total of 352 sand-blasted, thermally acid-etched titanium implants were inserted into 181 partially or completely edentulous patients. Their cumulative survival rate was evaluated retrospectively. Associated factors, such as the implant distribution and treatment type were included in the evaluation. Results: The implants were equally distributed between the maxilla (52.3%) and the mandible (47.7%). 48 implants (13.6%) were placed in the anterior region and 304 implants (86.4%) in the posterior region. The majority of the implants were inserted into bone of type II and III quality (89.8%) and volume (quantity B and C, 87.2%). Most of the implants (70.7%) were restored as single crowns; 28.7% supported a bridge construction and 0.6% a full denture. Only one implant failed, resulting in a four-year cumulative survival rate of 99.7%. Conclusions: The implant system showed an excellent four-year survival rate. It proved to be a safe and predictable means for restoration of the dentition in partially or completely edentulous patients.

• 구강회복응용과학지
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• 제34권4호
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• pp.280-289
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• 2018

목적: 이 연구의 목적은 임플란트의 길이 및 치관-임플란트 비율(crown-to-implant (C/I) ratio)이 임플란트의 안정성과 임플란트 변연골 소실량(MBL)에 영향을 주는지 알아보기 위함이다. 연구 재료 및 방법: 연구대상자로 하악 구치부에 단일치를 상실한 46명의 환자를 선별하였다. 대조군에는 총 19개의 직경 5.0 mm, 길이 10 mm의 임플란트(CMI IS-III $active^{(R)}$ long implant)를 식립하였고, 실험군에는 직경 5.5 mm, 길이 6.6, 7.3, 8.5 mm의 임플란트 총 27개(CMI IS-III $active^{(R)}$ short implant)를 식립하였다. 각각의 임플란트는 디지털 방식으로 술 전 제작한 수술가이드를 사용하여 식립하였고 임시보철물을 장착하여 즉시부하를 시행하였다. 술 후 3개월에 CAD-CAM 방식으로 제작한 지르코니아 크라운으로 최종 수복하였다. 술 후 48주에 ISQ 값과 변연골 소실량을 측정하여 치관-임플란트 비율과 ISQ 및 변연골 소실량 간의 상관관계를 비교하였다. 결과: 두 그룹 모두 안정도 및 변연골 소실량 면에서 성공적인 결과를 나타내었다. 술 후 48주에 측정한 두 그룹간 ISQ와 변연골 소실량 값은 통계적으로 유의미한 차이가 없었다(P > 0.05). 치관-임플란트 비율과 안정성 및 치관-임플란트 비율과 변연골 소실량 간에 어떤 상관관계도 관찰되지 않았다(P > 0.05). 결론: 두 그룹의 하악 단일 임플란트에서 치관-임플란트 비율은 안정성 및 변연골 소실량에 영향을 주지 않는 것으로 나타났다. 골높이가 부족한 하악에서 단일 임플란트 수복 시, 짧은 임플란트는 상대적으로 높은 치관-임플란트 비율에도 불구하고 제한된 조건 하에서 적절한 대안이 될 수 있다.

• 대한치과보철학회지
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• 제44권3호
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• pp.295-313
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• 2006

Statement of problem. Higher fracture rates were reported for Branemark implants placed in the maxilla and for 3.75 mm diameter implants installed in the posterior region. Purpose. The purpose of this study was to investigate the fracture of a fixture by finite element analysis and to compare different diameter of fixtures according to the level of alveolar bone resorption. Material and Methods. The single implant and prosthesis was modeled in accordance with the geometric designs for the 3i implant systems. Models were processed by the software programs HyperMesh and ANSA. Three-dimensional finite element models were developed for; (1) a regular titanium implant 3.75 mm in diameter and 13 mm in length (2) a regular titanium implant 4.0 mm in diameter and 13 mm in length (3) a wide titanium implant 5.0 mm in diameter and 13 mm in length each with a cementation type abutment and titanium alloy screw. The abutment screws were subjected to a tightening torque of 30 Ncm. The amount of preload was hypothesized as 650 N, and round and flat type prostheses were 12 mm in diameter, 9 mm in height were loaded to 600 N. Four loading offset points (0, 2, 4, and 6 mm from the center of the implants) were evaluated. To evaluate fixture fracture by alveolar bone resorption, we investigated the stress distribution of the fixtures according to different alveola. bone loss levels (0, 1.5, 3.5, and 5.0 mm of alveolar bone loss). Using these 12 models (four degrees of bone loss and three implant diameters), the effects of load-ing offset, the effect of alveolar bone resorption and the size of fixtures were evaluated. The PAM-CRASH 2G simulation software was used for analysis of stress. The PAM-VIEW and HyperView programs were used for post processing. Results. The results from our experiment are as follows: 1. Preload maintains implant-abutment joint stability within a limited offset point against occlusal force. 2. Von Mises stress of the implant, abutment screw, abutment, and bone was decreased with in-creasing of the implant diameter. 3. With severe advancing of alveolar bone resorption, fracture of the 3.75 and the 4.0 mm diameter implant was possible. 4. With increasing of bending stress by loading offset, fracture of the abutment screw was possible.

• 대한치과보철학회지
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• 제41권4호
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• pp.519-531
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• 2003

Statement of problem : Chronic implant screw loosening remains a problem in restorative practices. Some implant manufactureres have introduced abutment screws with treated material, surfaces and macrostructures in an effort to reduce potential loosening. Purpose : This study evaluated the materials and loading cycles on detorque value after dynamic continous fatigue test in the sinulated conditions of posterior single restoration. Material and method : Fourteen of each of the following abutment screws - titanium alloy, gold alloy, gold-tite, and titanium alloy modified - were used in test. SEM is used to verify macrostructures of each screws. $ZrO_2/Al_2O_3$ composite abutment was tightened on $4{\times}10.0mm$ titanium external implant at 30 Ncm. Cyclic loading machine delivered dynamic loading forces between 20 and 320N for 100,000, 200,000, 300,000, 500,000, and 1,000,000 cycles at frequencies 14Hz. Torque and detorque value after loading was measured. Results : All measued screws had different screw length and thread form. Titanium modified screw had greater detorque value than others before and after cyclic loadings(p<0.05). All abutment screws had no significant change in mean percentage of detorque value after loading to initial value after less than 500.000 cyclic loadings, but significant lower value after 1,000,000 cycles(p<0.05). Conclusion : Within limintations of this study all abutment screws may be loosend after about 1 year use. Annual check-up is nessasary to prevent screw loosening.

• The Journal of Advanced Prosthodontics
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• 제13권6호
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• pp.396-407
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• 2021

PURPOSE. Zirconia has exceptional biocompatibility and good mechanical properties in clinical situations. However, finite element analysis (FEA) studies on the biomechanical stability of two-piece zirconia implant systems are limited. Therefore, the aim of this study was to compare the biomechanical properties of the two-piece zirconia and titanium implants using FEA. MATERIALS AND METHODS. Two groups of finite element (FE) models, the zirconia (Zircon) and titanium (Titan) models, were generated for the exam. Oblique (175 N) and vertical (175 N) loads were applied to the FE model generated for FEA simulation, and the stress levels and distributions were investigated. RESULTS. In oblique loading, von Mises stress values were the highest in the abutment of the Zircon model. The von Mises stress values of the Titan model for the abutment screw and implant fixture were slightly higher than those of the Zircon model. Minimum principal stress in the cortical bone was higher in the Titan model than Zircon model under oblique and vertical loading. Under both vertical and oblique loads, stress concentrations in the implant components and bone occurred in the same area. Because the material itself has high stiffness and elastic modulus, the Zircon model exhibited a higher von Mises stress value in the abutments than the Titan model, but at a level lower than the fracture strength of the material. CONCLUSION. Owing to the good esthetics and stress controllability of the Zircon model, it can be considered for clinical use.