• The Journal of Advanced Prosthodontics
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• 제14권2호
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• pp.108-121
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• 2022

PURPOSE. The purpose of this study was to evaluate survival rates and marginal bone loss (MBL) of implants in IC-RPDs. MATERIALS AND METHODS. Seventy implants were placed and used as surveyed crowns in 30 RPDs. The survival rates and MBL around implants based on multiple variables, e.g., position, sex, age, opposing dentitions, splinting, type of used retainer, and first year bone loss, were analyzed. Patient reported outcome measures (PROMs) regarding functional/esthetic improvement after IC-RPD treatment, and complications were also inspected. RESULTS. The 100% implant survival rates were observed, and 60 of those implants showed MBL levels less than 1.5 mm. No significant differences in MBL of implants were observed between implant positions (maxilla vs. mandible; P = .341) and type of used retainers (P = .630). The implant MBL of greater than 0.5 mm at 1 year showed significantly higher MBL after that (P < .001). Splinted implant surveyed crowns showed lower MBL in the maxilla (splinted vs. non-splinted; P = .037). There were significant esthetic/functional improvements observed after treatment, but there were no significant differences in esthetic results based on implant position (maxilla vs. mandible). Implants in mandible showed significantly greater improvement in function than implants in the maxilla (P = .002). Prosthetic complication of IC-RPD was not observed frequently. However, 2 abutment teeth among 60 were failed. The bone loss of abutment teeth was lower than MBL of implants in IC-RPDs (P = .001). CONCLUSION. Class I RPD connected to residual teeth and strategically positioned implants as surveyed crowns can be a viable treatment modality.

• The Journal of Advanced Prosthodontics
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• 제14권1호
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• pp.22-31
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• 2022

PURPOSE. The purpose of this study was to investigate the misfit and screw preload at the implant abutment connection of implant supported fixed dental prosthesis with cantilever (ICFDP) manufactured using different digital manufacturing techniques and to compare the screw preload before and after cyclic loading. MATERIALS AND METHODS. Mandibular jaw model with four intra-foraminal implants was scanned using digital scanner. Stereolithography file was used to design a framework with nonengaging (NE) abutments and 10 mm cantilever distal to one terminal implant. Five frameworks were constructed using combined digital-conventional techniques (CAD-cast), and five frameworks were constructed using three-dimensional printing (3DP). Additional CAD-cast framework was constructed in a way that ensures passive fit (PF) to use as control. Scanning electron microscope (SEM) measured the implant abutment connection misfit. Sixty screws were used on the corresponding frameworks. Screws were torqued and pre-cyclic loading reverse torque value (RTV) was recorded. Frameworks were subjected to 200,000 loading cycles with a loading point 9 mm from the center of terminal implants adjacent to the cantilever and post-cyclic loading RTVs were recorded. RESULTS. Microscopic readings showed significant differences between frameworks. PF demonstrated the lowest measurements of 16.04 (2.6) ㎛ while CAD-cast demonstrated the highest measurements of 29.2 (3.1) ㎛. In all groups, RTVs were significantly lower than the applied torque. Post-cyclic loading RTV was significantly lower than pre-cyclic loading RTV in PF and 3DP frameworks. Differences in RTVs between the three manufacturing techniques were insignificant. CONCLUSION. Although CAD-cast and three-dimensionally printed (3DP) both produce frameworks with clinically acceptable misfit, 3DP might not be the technique of choice for maintaining screw's preload stability under an aggressive loading situation.

• 대한치과보철학회지
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• 제46권4호
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• pp.396-408
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• 2008

연구목적: 임플랜트 치료에서 가장 흔히 발생하는 기계적 문제점 중 하나는 나사의 풀림이다. 지대주 나사에 조임회전력을 가하는 목적은 나사를 신장시켜, 신장된 나사의 인장력에 의한 지대주와 고정체간의 압축력을 통해 연결부의 안정성을 부여하는 데 있다. 조임 회전력의 결과로 나타나는 전하중의 크기는 다양한 요소에 의해 영향을 받기 때문에, 동일한 조임회전력을 적용하였다 할지라도 임플랜트 시스템의 종류에 따라 전하중의 크기가 달라질 수 있다. 따라서 지대주 나사 연결부의 안정성을 위한 다양한 임플랜트 시스템의 적정 조임회전력 크기에 관한 연구가 필요하다. 본 연구에서는 external butt joint와 두 가지 internal cone 연결형태를 갖는 임플랜트 시스템들에서 지대주 나사의 조임회전력이 임플랜트-지대주 나사 연결부의 안정성에 미치는 영향을 하중 전후의 풀림회전력 측정을 통해 알아보고자 하였다. 연구재료 및 방법: External butt joint 형태를 가지는 US II 시스템과 $8^{\circ}$ internal cone 연결형태의 SS II 및 $11^{\circ}$ internal cone 연결형태의 GS II 시스템에서 20 Ncm, 30 Ncm, 그리고 40 Ncm의 각기 다른 조임회전력을 적용한 후 초기 풀림회전력 및 상실률과 $10^5$회의 반복하중 후의 풀림회전력 및 상실률을 비교 분석하였다. 연구결과 및 결론: 1. 초기 풀림회전력과 하중 후 풀림회전력은 조임회전력의 크기가 증가할수록 크게 나타났다 (P < .05). 2. 초기 풀림회전력 상실률은 SS II 시스템에서는 조임회전력 크기에 따른 차이가 없었으나 (P > .05), GS II와 US II에서는 20 Ncm 보다 40Ncm의 조임회전력에서 더 낮게 나타났다 (P < .05). 3. 하중 후 풀림회전력 상실률은 세 시스템 모두 30 Ncm의 조임회전력을 가했을 때 가장 낮게 나타났다 (P < .05). 4. 하중 후 풀림회전력 상실률은 SS II, GS II, 그리고 US II 순으로 높아지는 경향을 보였다. 5. 초기 풀림회전력과 하중 후 풀림회전력 상실률 간에는 상관관계가 없었다 (P > .05). 이상의 결과로부터 임플랜트 시스템의 종류뿐만 아니라 조임회전력의 크기 또한 지대주 나사의 풀림회전력 상실에 영향을 준다는 것을 알 수 있다. 따라서 임플랜트-지대주 나사 연결부 안정성 유지를 위해서는 임플랜트 시스템마다 적정 조임회전력이 제시되어야 하고, 또한 임상에서 이를 준수하는 것이 매우 중요하다고 생각된다.

• 구강회복응용과학지
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• 제32권4호
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• pp.263-273
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• 2016

지대주의 재료와 표면에 따라 연조직반응이 다르고 임플란트 주위염의 원인이 될 수 있다. 티타늄과 지르코니아는 우수한 생체적합성을 가져 안정적인 연조직반응을 보이고 금합금은 표면상태에 따라 연조직반응이 다르게 나타난다. 같은 재료라도 표면특성에 따라 연조직반응이 영향을 받는다. 표면거칠기 증가는 박테리아 부착을 유발하므로 연조직과 접촉하는 부분은 평활한 표면을 가져야 한다. 추가적인 표면처리를 통해 박테리아의 부착은 증가시키지 않으면서 세포반응을 촉진시킬 수 있다. 지대주의 형태 및 반복착탈도 연조직반응에 영향을 줄 수 있다. 초음파 세척과 아르곤 플라즈마 처리는 비교적 효과적으로 맞춤형 지대주의 잔류 미세입자를 제거할 수 있는 방법이다.

• 구강회복응용과학지
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• 제40권2호
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• pp.64-71
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• 2024

목적: 본 연구의 목적은 세 가지 높이를 가진 티타늄 베이스 임플란트 지대주에서 세 종류의 시멘트가 지르코니아 수복물에서 가지는 제거력을 비교하는 것이다. 연구 재료 및 방법:. 90개의 직경 4.0 mm 임플란트 아날로그가 레진 블록에 식립되었다. 이후 3 mm, 5 mm, 7 mm의 높이를 가지도록 임플란트 지대주를 30개씩 제작하였고, 각 지대주를 스캔하여 지르코니아 수복물 시편을 제작하였다. 임시 시멘트(TB), 반영구 시멘트(CI), 영구 시멘트(FC)를 각자 제조사의 지시에 따라 지대주에 접착하였다. 제작된 90개의 시편은 만능시험기에서 제거력을 시험하였으며, 모든 제거력은 부하량이 하락하기 직전 가장 높은 값에서 측정되었다. 통계 분석은 지대주의 높이, 시멘트의 종류에 대해 각각 Kruskal-Wallis test (P = 0.05) 후 Mann-Whitney U test (P = 0.0167)로 사후 검정 시행하였다. 결과: 임플란트 지대주의 높이에 상관없이 TB에 비해 FC의 제거력이 높았다. CI와 FC간에는 3 mm와 7 mm에서는 유의미한 차이가 있었으나 5 mm에서는 유의미한 차이가 없었다. TB와 CI간에는 5 mm에서만 유의미한 차이가 있었다. 결론: 시멘트의 종류는 지르코니아 수복물의 제거력에 유의미한 영향을 끼쳤으나, 임플란트 지대주의 높이는 유의미한 영향을 주지 않았다.

• 대한치과의사협회지
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• 제38권6호통권373호
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• pp.558-566
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• 2000

Osseointegrated dental implants have now become and accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of AVANA implant-Korea. A total of 323 AVANA implants were placed at 9 centers in the edentulous and partially edentulous jaws of 88 consecutive patients ranging in age form 18 to 79 years. So we get the clinical results. 1. Both patients (94.4%) & doctors (94%) were satisfied with the results, in patient's aspect 'most satisfaction' case were more common(52%) 2. The length of fixture which was frequently used was 13mm (168/319,44.5%) followed by 15mm and 10mm, and 3.75mm width implant (239/319,74.9%) was the most popularly used. 3. Mandibutar posterior was the most common installation site (140/317.43%) 4. A mean implant survival rate was 96.2%. That showed little difference which reported other paper. Cause of failure consisted of inflammation $ infection-36%, fall of osseointegration-18%, paln during masticatory function-9%. improper prosthetic function $ procedure-9%. 5. The most popularly used types of abutment was the UCLA abutment(168/305,55.5%)

• 대한치과보철학회지
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• 제39권3호
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• pp.306-312
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• 2001

Achieving an aesthetic implant-supported restoration in the single tooth missing case can be challenging when the implant site is in e anterior region. The objective of this report is to focus on presurgical evaluation of implant site and systematic development of related prosthetic modalities. An accurate diagnostic evaluation, a systematically developed pesurgical plan, and knowledge and clinical skill of the various related therapeutic modalities are indispensible. Collection of patient's information, appropriate abutment selection, soft tissue contour, implant axis, and occlusion need to be discussed for aesthetic clinical outcome. For aesthetic restoration, such as surgical guide stent for precise implant positioning customized provisional restoration for development of optimal periimplant soft tissue contours, and fabrication customized abutment (mesiostructure) for veriable emergence profile, are recommended.

• The Journal of Advanced Prosthodontics
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• 제13권4호
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• pp.216-225
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• 2021

PURPOSE. The aim of this study is to evaluate the effects of canine guidance occlusion and group function occlusion on the degree of stress to the bone, implants, abutments, and crowns using finite element analysis (FEA). MATERIALS AND METHODS. This study included the implant-prosthesis system of a three-unit bridge made of monolithic zirconia and hybrid abutments. Three-dimensional (3D) models of a bone-level implant system and a titanium base abutment were created using the original implant components. Two titanium implants, measuring 4 × 11 mm each, were selected. The loads were applied in two oblique directions of 15° and 30° under two occlusal movement conditions. In the canine guidance condition, loads (100 N) were applied to the canine crown only. In the group function condition, loads were applied to all three teeth. In this loading, a force of 100 N was applied to the canine, and 200-N forces were applied to each premolar. The stress distribution among all the components of the implant-bridge system was assessed using ANSYS SpaceClaim 2020 R2 software and finite element analysis. RESULTS. Maximum stress was found in the group function occlusion. The maximum stress increased with an increase in the angle of occlusal force. CONCLUSION. The canine guidance occlusion with monolithic zirconia crown materials is promising for implant-supported prostheses in the canine and premolar areas.

• Journal of Periodontal and Implant Science
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• 제36권2호
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• pp.531-554
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• 2006

Oral implants must fulfill certain criteria arising from special demands of function, which include biocompatibility, adequate mechanical strength, optimum soft and hard tissue integration, and transmission of functional forces to bone within physiological limits. And one of the critical elements influencing the long-term uncompromise functioning of oral implants is load distribution at the implant- bone interface, Factors that affect the load transfer at the bone-implant interface include the type of loading, material properties of the implant and prosthesis, implant geometry, surface structure, quality and quantity of the surrounding bone, and nature of the bone-implant interface. To understand the biomechanical behavior of dental implants, validation of stress and strain measurements is required. The finite element analysis (FEA) has been applied to the dental implant field to predict stress distribution patterns in the implant-bone interface by comparison of various implant designs. This method offers the advantage of solving complex structural problems by dividing them into smaller and simpler interrelated sections by using mathematical techniques. The purpose of this study was to evaluate the stresses induced around the implants in bone using FEA, A 3D FEA computer software (SOLIDWORKS 2004, DASSO SYSTEM, France) was used for the analysis of clinical simulations. Two types (external and internal) of implants of 4.1 mm diameter, 12.0 mm length were buried in 4 types of bone modeled. Vertical and oblique forces of lOON were applied on the center of the abutment, and the values of von Mises equivalent stress at the implant-bone interface were computed. The results showed that von Mises stresses at the marginal. bone were higher under oblique load than under vertical load, and the stresses were higher at the lingual marginal bone than at the buccal marginal bone under oblique load. Under vertical and oblique load, the stress in type I, II, III bone was found to be the highest at the marginal bone and the lowest at the bone around apical portions of implant. Higher stresses occurred at the top of the crestal region and lower stresses occurred near the tip of the implant with greater thickness of the cortical shell while high stresses surrounded the fixture apex for type N. The stresses in the crestal region were higher in Model 2 than in Model 1, the stresses near the tip of the implant were higher in Model 1 than Model 2, and Model 2 showed more effective stress distribution than Model.

• 대한치과보철학회지
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• 제43권5호
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• pp.671-683
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• 2005

Statement of problem: The most commonly reported problem associated with dental implant restoration is the loosening of the screws. Purpose: This study compared the efficacy of an implant system incorporating an anti-rotational locking sleeve(Anti-Rotating Inner Post Screw System(ARIPS-system)) with other, traditional implant systems as a means of minimizing vibration loosening. Materials and methods: Three implant systems were examined; the conventional external hex type, the ARIPS-system, and the internal taper type implant system 30 specimens(10 samples per group)were fabricated and each abutment screw was secured to the implant future with 32Ncm of torque force and loosening torque was measured using a Torque Gauge. The procedure was repeated 3 times, recording initial loosening torque each time. The re-tightened abutment screw was subjected to a cyclic load having a maximum forte of 200N and minimum of 20N at 2Hz over a period of 12,600 cycles. after which the loosening torque was measured. Measured values were calaulated for statistical analysis. Analysis of measured value was performed by 3 methods: (i) as a percentage average of the initial 3 loosening-torque values(initial loosening value) to the tightening torque of 32Ncm, (ii) as a percentage of the loosening torque value after a load of 200N(experimental value) to the initial loosening value, and (iii) as a percentage of the experimental value to the 32Ncm of tightening torque. The analyses shows the amount of initial loosening at the screw, loosening by repetitive load and the the final loosening value. Results: The results of this study were as follows (1) Percentage of initial loosening value to tightening-torque was increased in order of external hex, ARIPS-system and internal taper and all values between each groups showed statistical significance (p<0.05). (2) Percentage of experimental value to initial loosening value was increased in order of external hex, ARIPS-system and internal taper. Value of internal taper showed significant difference with those of external hex and ARIPS-system (p<0.05). (3) Percentage of experimental value to tightening torque was increased in order of external hex, ARIPS-system and internal taper and all values between each groups showed statistical significance (p<0.05). Conclusion: The results of the analysis of the final loosening level value, which are closely correlated to clinical use, show that the ARIPS-system can be a useful means of minimizing abutment screw loosening when compared to the external hex type system. Although further clinical studies need to be made, the ARIPS-system should be considered to maximize the long-term success of the implant prosthesis.