• The Journal of Advanced Prosthodontics
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• 제7권4호
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• pp.288-293
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• 2015

PURPOSE. The aim of this study was to evaluate the effect of cyclic loading and screw retightening on reverse torque value (RTV) in external and internal type implants. MATERIALS AND METHODS. Cement-retained abutments were connected with 30 Ncm torque to external and internal type implants. Experimental groups were classified according to implant connection type and retightening/loading protocol. In groups with no retightening, RTV was evaluated after cyclic loading for 100,000 cycles. In groups with retightening, RTV was measured after 3, 10, 100 cycles as well as every 20,000 cycles until 100,000 cycles of loading. RESULTS. Every group showed decreased RTV after cyclic loading. Before and after cyclic loading, external type implants had significantly higher RTVs than internal type implants. In external type implants, retightening did not affect the decrease in RTV. In contrast, retightening 5 times and retightening after 10 cycles of dynamic loading was effective for maintaining RTV in internal type implants. CONCLUSION. Retightening of screws is more effective in internal type implants than external type implants. Retightening of screws is recommended in the early stage of functional loading.

• 대한관절경학회:학술대회논문집
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• 대한관절경학회 2007년도 제17차 추계학술대회 심포지움
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• pp.8-8
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• 2007

• 한국산업융합학회 논문집
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• 제26권4_2호
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• pp.623-628
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• 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).

• 대한치과보철학회지
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• 제46권2호
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• pp.209-216
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• 2008

본 연구의 목적은 내측연결형 임플랜트와 일체형 지대주를 사용하여 최종 보철물을 시적한 뒤에 5만 번의 반복하중 후에 다시 체결하고 20만 번의 반복하중을 가한 후의 지대주 풀림토크와 20만 번의 반복하중을 받은 지대주 풀림토크가 어떻게 달라지는지를 비교하고자 하는 것이다. 실험 재료로는 타이타늄 지대주와 DLC 코팅된 지대주를 사용하였다. 실험군은 4군으로 모두 8개의 ITI SLA $4.1{\times}10mm$ 를 사용하였다. A군과 B군은 5만번, 20만번 반복하중을 가하고 Periotest값과 풀림 토크값을 측정하였으며 C군과 D군은 20만번 반복하중을 가하고 Periotest 값과 풀림토크값을 측정하였다. 풀림 토크값의 측정은 디지털 토크 게이지를 사용하였고, 반복하중은 MTS. (Bionix 850 II, MTS, U.S.A.)를 사용하였으며 100N/cm의 힘을 20도의 경사, 14Hz 의 조건으로 가하였다. A군과 C군은 코팅하지 않은 타이타늄 지대주를 사용하였으며, B군과 D군은 DLC 코팅한 지대주를 사용하였다. 1. 5만번 반복하중을 가한 뒤 측정한 풀림 토크는 B군에서 약간 더 큰 평균값을 보였다. 하지만 통계학적으로 두 군간에 유의한 차이를 보이지 않았다 (P>0.05). 2. 20만번 반복하중을 가한 뒤 측정한 최종 풀림 토크 값은 A군은 C군보다, B군은 D군보다 약간 더 큰 평균값을 보였으나 통계학적으로 두 군간에 유의한 차이를 보이지 않았다 (P>0.05). 3. 20만번 반복하중을 가한 최종 풀림 토크 값은 A, B군과 C, D군 사이에 통계학적으로 유의할 만한 차이가 없었다 (P>0.05).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권6호
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• pp.332-338
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• 2023

Objectives: This study aimed to compare the effectiveness of a hybrid arch bar (hAB) with the conventional Erich arch bar (EAB) for the management of jaw fractures, focusing on their use for temporary fixation in patients undergoing open reduction and internal fixation (ORIF). Materials and Methods: Patients presenting with maxillary and mandibular fractures at our institution were included in this prospective, comparative study. Placement time and ease of occlusal reproducibility were recorded intraoperatively for Group A (hAB patients) and Group B (EAB patients). The primary outcome was comparison of the postoperative stability of the two arch bars. Postoperative measurements also included mucosal overgrowth, screw loosening or wire retightening, and replacement rates. The data were tabulated and computed with a P<0.05 considered statistically significant. Results: The study included 41 patients. A statistically significant difference was observed in postoperative stability scores (3) between Group A and Group B (85.0% vs 9.5%, P=0.001). The mean placement time in Group A (23.3 minutes) significantly differed from that in Group B (86.4 minutes) (P<0.001). The ease of intraoperative occlusion was not different between the two groups (P=0.413). Mucosal overgrowth was observed in 75.0% of patients (15 of 20) in Group A. Conclusion: The hAB was superior to EAB in clinical efficiency, maxillomandibular fixation time reduction, stability, versatility, and safety. Despite temporary mucosal overgrowth, the benefits of hAB outweigh the disadvantages. The choice between hAB and EAB should be based on specific clinical requirements.

• 대한관절경학회지
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• 제13권3호
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• pp.280-284
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• 2009

목적: 버팀테응력 회복을 위한 아탈구 된 내측 반월상 연골의 봉합나사(suture anchor)를 이용한 관절경적 정복술을 보고하고자 한다. 수술 수기: 전외측, 전내측, 중슬개골 도달법을 기본으로 사용하였다. 전외측 도달법으로 관절경을 삽입하여 내측 반월상 연골판의 아탈구를 먼저 확인 하였으며, 내측 반월상 연골판의 방사선 파열이 있는 경우에는 이번 연구에서 제외 하였다. 전내측 삽입구를 통하여 내측 반월상 연골판의 전방부를 유리 시킨 후, 봉합 나사가 삽입 될 곳의 피질골을 전동식 연마기를 이용하여 제거하였다. 중슬개골 도달법을 이용하여 봉합 나사(suture anchor)를 삽입 하였으며, 90도의 봉합 갈고리와 2.0 Nylon을 이용하여 봉합 나사의 봉합사를 연골판에 통과 시킨 후, Sliding knot-tying technique을 사용하여 연골판을 고정시켰다. 환자들은 술 후 6주간 체중 부하를 금지 하였다. 결론: 내측 반월상 연골의 아탈구에 있어 최소한의 손상으로 버팀테응력 회복을 통하여 슬관절의 안정성을 증진시킬 수 있는 술식으로 봉합 나사(Suture Anchor)를 이용한 관절경적 정복술을 소개한다.