• The Journal of Advanced Prosthodontics
• /
• 제10권2호
• /
• pp.155-162
• /
• 2018

PURPOSE. The aim of this study was to compare the fracture of implant component behavior of external and internal type of implants to suggest directions for successful implant treatment. MATERIALS AND METHODS. Data were collected from the clinical records of all patients who received WARANTEC implants at Seoul National University Dental Hospital from February 2002 to January 2014 for 12 years. Total number of implants was 1,289 and an average of 3.2 implants was installed per patient. Information about abutment connection type, implant locations, platform sizes was collected with presence of implant component fractures and their managements. SPSS statistics software (version 24.0, IBM) was used for the statistical analysis. RESULTS. Overall fracture was significantly more frequent in internal type. The most frequently fractured component was abutment in internal type implants, and screw fracture occurred most frequently in external type. Analyzing by fractured components, screw fracture was the most frequent in the maxillary anterior region and the most abutment fracture occurred in the maxillary posterior region and screw fractures occurred more frequently in NP (narrow platform) and abutment fractures occurred more frequently in RP (regular platform). CONCLUSION. In external type, screw fracture occurred most frequently, especially in the maxillary anterior region, and in internal type, abutment fracture occurred frequently in the posterior region. placement of an external type implant rather than an internal type is recommended for the posterior region where abutment fractures frequently occur.

• 한국표면공학회지
• /
• 제48권6호
• /
• pp.283-291
• /
• 2015

The purpose of this study was to investigate effects of TiN coating on the fatigue fracture of dental implant system with various cyclic loads. TiN coated abutment screw, the fixture, and abutment of internal hex type were prepared for fatigue test. The fatigue test was carried out according to ISO 14801:2003(E) using tensile and compression tester with repeated load from 30% to 80% of static fracture force. Morphology and fractured surface was observed by field emission scanning electron microscope(FE-SEM) and energy dispersive X-ray spectroscope(EDS). The fracture cycle drastically decreased as repeated load increased. Especially, in the case of TiN-coated abutment screw, fracture cycle increased compared to non-coated abutment screw. The fatigue crack was propagated fast as repeated load increased. The plastic deformation region decreased, whereas, cleavage fracture region increased as repeated load increased.

• Journal of Korean Dental Science
• /
• 제6권1호
• /
• pp.27-33
• /
• 2013

The introduction of osseointegrated dental implants in dentistry brought about a new era in everyday dental practice. For the past 50 years, prosthetic restoration with implant-supported prosthesis has developed into a viable and predictable treatment option. Alongside the increasing use of dental implants is the occurrence of many complications during implant placement (surgery), in the mechanical or prosthetic problem, and in the biological aspect. In particular, abutment or screw fracture as one of the mechanical complications can put the dentist in a tight spot in a clinical situation. It is hard to remove the fractured abutment and screw to restore it properly. Therefore, it is very important that clinicians consider possible complications in advance and make an appropriate treatment plan. We discuss cases of abutment fracture and mechanical/prosthetic complications together with the causes and solutions.

• 대한치과보철학회지
• /
• 제57권1호
• /
• pp.37-41
• /
• 2019

치과 임플란트는 상실된 치아의 수복에 효과적이고 예측 가능한 치료 방법이다. 하지만 임플란트 사용이 증가함에 따라 합병증도 증가하고 있다. 이 중 기계적 합병증은 발생 빈도가 높을 뿐 아니라 임플란트의 수명이 길어질수록 더 많이 발생하므로 이에 대한 대책이 필요하다. 이에 임플란트의 가장 흔한 기계적 합병증인 지대주 파절과 지대주 나사 파절의 증례에서 파손된 부위만 재제작하여 파손되지 않은 구성요소를 최대한 보존할 수 있는 방법을 소개하고자 한다.

• 대한치과보철학회지
• /
• 제55권1호
• /
• pp.9-17
• /
• 2017

목적: 내부 연결형과 외부 연결형의 임플란트에서 직선형과 경사형 지르코니아 지대주의 파절강도를 비교하였다. 재료 및 방법: 내부육각 연결형 임플란트 20개와 외부육각 연결형 임플란트 20개에, 기성 직선형 지르코니아 지대주와, $17^{\circ}$ 경사형 지르코니아 지대주를 10개씩 체결하였다. 시편은 연결 방식과 지대주 각도에 따라 4개의 군으로 나누었다: 내부 연결형/ 직선형 지대주, INS군; 내부 연결형/ 경사형 지대주, INA 군; 외부 연결형/ 직선형 지대주, EXS 군; 외부 연결형/ 경사형 지대주, EXA 군. 모든 시편은 만능시험기에서 1 mm/min의 crosshead speed로 $30^{\circ}$ 하중을 가했다. 지대주의 파절강도를 측정하고, 2-way ANOVA와 independent t-test로 통계처리 하였다(${\alpha}=.05$). 결과: 각 군의 평균파절강도는 다음과 같다: INS군, 955.91 N; INA군, 933.65 N; EXS군, 1267.20 N; EXA군, 1405.93 N. 외부 연결형이 내부 연결형에 비해 파절강도가 높았다(P < .001). 내부연결형(P = .747)과 외부 연결형(P = .222)에서 지대주 각도에 따른 파절강도는 차이가 없었다. 또한 내부 연결형 지대주는 육각 부위에서 수평 파절이 일어난 반면, 외부 연결형 지대주는 설측 치경부에서 파절되었다. 결론: 외부 연결형 지르코니아 지대주가 내부 연결형 지대주에 비해 파절 강도가 높았고, 직선형과 경사형 지르코니아 지대주의 파절강도는 차이가 없었다.

• 한국산업융합학회 논문집
• /
• 제26권4_2호
• /
• pp.623-628
• /
• 2023

The purpose of this study was to evaluate the fracture strength and removal torque value (RTV) of a conventional angled abutment and a newly developed angled abutment (Beauty up abutment) with an angulated screw access hole. Each abutment was divided into a control group and an experimental group (n = 20, respectively). To measure the fracture strength, the abutment was connected to the internal hex implant with 30 Ncm torque, and a load was applied at 30 degree angle with cross-head speed of 1 mm/min using a universal testing machine according to the ISO 14801:2016 standard. To measure RTV, each abutment was fastened to the implant with 30 Ncm torque. Retightening was performed after 10 minutes, and initial RTV was measured with a digital torque gauge. After retightening, a load of 250 N was applied to the abutment at a 30 degree angle using a chewing simulator. After a total of 100,000 repeated loads, RTV was measured. Statistical analysis was performed using Wilcoxon signed rank test and Mann-Whitney U test (α = .05). The fracture strength of the experimental group was statistically significantly lower than that of the control group (P = .009). There was no significant difference between initial RTV and post-loading RTV between the experimental group and the control group (P = .753, P = .527, respectively), and cyclic loading did not significantly affect RTV in both groups (P = .078).

• 대한치과의사협회지
• /
• 제53권9호
• /
• pp.644-655
• /
• 2015

Purpose: This study was conducted to evaluate the effect of the fixture abutment connection type and diameter on the screw joint stability in external butt joint for 2nd surgery and internal cone connected type implant system for 1st and 2nd surgery using ultimate fracture strength. Materials and Methods: USII system, SSII system and GSII system of Osstem Implant were used. Each system used the fixture with two different diameters and cement-retained abutments, and tungsten carbide / carbon coated abutment screws were used. Disc shaped stainless steel metal tube was attached using resin-based temporary cement. The experimental group was divided into seven subgroups, including the platform switching shaped specimen that uses a regular abutment in the fixture with a wide diameter in USII system. A static load was increased to the metal tube at 5mm deviated point from the implant central axis until it reached the compression bending strength at a rate of 1mm/min. Then the deformations and patterns of fracture in threaded connection were compared. Results and Conclusion: 1. In the comparison between the Regular diameter, compression bending strength of SSII system was higher than USII system and GSII system. There was no significant difference between USII system and GSII system. 2. In the comparison between wide diameter, compression bending strength was increased in the order of GSII system, USII system, and SSII system. 3. In comparison between the implant diameter, compression bending strength of the wide diameter was greater than the regular diameter in any system(P<0.05). 4. There was no significant difference between the platform switching (III group) and the regular diameter (I group) in USII system. 5. In USII system, fracture of abutment screw and deformation of both fixture and abutment were observed in I, II and III subgroups. 6. Failure pattern of SSII system, which was the fracture of abutment screw and deformation of the abutment and fixture, was observed in both IV and V subgroups. Fracture of some fixtures was observed in subgroup V. 7. Failure pattern of GSII system, which was the fracture of the abutment screw and deformation of the fixture and the abutment, was observed in both VI and VII subgroups. Apart from other subgroups, subgroup VII demonstrated no bending neither the fracture at the top of the fixture. The compressive deformation of internal slope in the fixture was the only thing observed in subgroup VII.

• 한국산업융합학회 논문집
• /
• 제20권2호
• /
• pp.169-176
• /
• 2017

Dental implants are required to have biomechanical functions and biostability in order to perform authoring, pronunciation, and aesthetic functions in the oral cavity. In terms of biostability, pure titanium for medical have good biostability and no rejection in the alveolar bone. with appropriate strength in terms of strength as well as biocompatibility. In recent years, various surgical methods and devices have been developed to improve the convenience and safety of the procedure. However, as the number of procedures increases, the screw loosening of the abutment screw connecting the artificial root and the abutment There are many reports of artificial root and abutment fracture. Fig. 1 is an example of a case where the upper part of the abutment screw is arbitrarily modified to remove the abutment by the abutment fracture due to the loosening of the abutment screw. The fundamental cause of abduction of the abutment screw is caused by the slight movement due to the lowering of the retention force of the abutment screw. It is necessary to minimize loosening of the abutment screw to avoid problems such as fracture during the period of using the implant. The purpose of this study is to investigate the structure of the abutment screw to prevent the loosening of the abutment screw by forming 0.5mm slot.

• 구강회복응용과학지
• /
• 제36권2호
• /
• pp.61-69
• /
• 2020

목적: 하악 제2소구치와 제2대구치를 지대치로 한 지르코니아 고정성 국소의치에서 지대치 간 거리가 파절저항성에 미치는 영향을 조사하였다. 연구 재료 및 방법: Cameleon S zirconia block과 Luxen S2 zirconia block으로 각 재료별 지대치 간 거리를 달리 하여 CS군과 S2군으로 나누어 표기하였으며, 소결된 지르코니아 고정성 국소의치를 임시접착시멘트를 이용하여 에폭시 레진 다이에 합착하였다. 이후, 가공치 교합면에 직경 6 mm 강철구를 위치시켜 로드셀 5.0 kN의 universal testing machine에서 크로스 헤드 속도 1.0 mm/min로 압력을 가하여 파절저항성을 측정하였다. 결과: 지르코니아 고정성 국소의치의 파절저항성은 지대치 간 거리에 큰 영향을 받지 않았다. CS군에서 지대치 간 거리가 15 mm인 경우가 13 mm와 17 mm인 경우보다 파절저항성이 유의하게 높았다(P < 0.05). S2군에서는 파절저항성이 세 군 간에 유의한 차이가 없었다(P > 0.05). 결론: 하악 제2소구치와 제2대구치를 지대치로 한 지르코니아 고정성 국소의치에서 지대치 간 거리는 지르코니아의 종류에 따라 파절저항성에 영향을 줄 수 있다.

• The Journal of Advanced Prosthodontics
• /
• 제7권6호
• /
• pp.423-430
• /
• 2015

PURPOSE. To evaluate the cumulative survival rate (CSR) and mechanical complications of single-tooth $Ankylos^{(R)}$ implants. MATERIALS AND METHODS. This was a retrospective clinical study that analyzed 450 single $Ankylos^{(R)}$ implants installed in 275 patients between December 2005 and December 2012. The main outcomes were survival results CSR and implant failure) and mechanical complications (screw loosening, fracture, and cumulative fracture rate [CFR]). The main outcomes were analyzed according to age, sex, implant length or diameter, bone graft, arch, and position. RESULTS. The 8-year CSR was 96.9%. Thirteen (2.9%) implants failed because of early osseointegration failure in 3, marginal bone loss in 6, and abutment fracture in 4. Screw loosening occurred in 10 implants (2.2%), and 10 abutment fractures occurred. All abutment fractures were located in the neck, and concurrent screw fractures were observed. The CSR and rate of screw loosening did not differ significantly according to factors. The CFR was higher in middle-aged patients (5.3% vs 0.0% in younger and older patients); for teeth in a molar position (5.8% vs 0.0% for premolar or 1.1% for anterior position); and for larger-diameter implants (4.5% for 4.5 mm and 6.7% for 5.5 mm diameter vs 0.5% for 3.5 mm diameter) (all P<.05). CONCLUSION. The $Ankylos^{(R)}$ implant is suitable for single-tooth restoration in Koreans. However, relatively frequent abutment fractures (2.2%) were observed and some fractures resulted in implant failures. Middle-aged patients, the molar position, and a large implant diameter were associated with a high incidence of abutment fracture.