• 대한치과보철학회지
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• 제52권4호
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• pp.279-286
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• 2014

목적: 임플란트가 식립되는 동적과정을 유한요소해석으로 모사하여, 임플란트 나사형상 차이가 변연골의 식립 응력발생에 미치는 영향을 조사하고자 한다. 재료 및 방법: 코어직경 3.5 mm, 매식부 길이 10 mm인 Straumann 임플란트 몸체 외형에 서로 다른 4종의 나사산이 부여된 가상의 임플란트 모델 4개를 CAD 프로그램을 이용하여 각각 제작하였다. 4종 나사산은 buttress 형, v-자 형, reverse buttress 형, square 형이며, 나사산의 높이와 피치는 0.3 mm와 1.0 mm로 모두 동일하다. 각 임플란트가 3.8 mm pilot hole을 갖는, 1.2 mm 두께 치밀골에 식립되는 과정을 $DEFORM^{TM}$ 3D (ver. 6, SFTC, Columbus, OH, USA) 프로그램을 사용하여 모사/해석하였으며, 식립이 진행되는 과정에 인접골에 생성/누적되는 응력(식립응력)을 비교 분석하였다. 결과: 임플란트 식립 초기, 그 하단부가 pilot hole 내로 진입하며 나사산이 골벽을 압박/변형시키는 단계에서 식립 토오크와 응력이 급격히 발생하였으며 그 이후에 토오크와 응력이 모두 감소하는 변화를 보였다. 식립 응력은 임플란트 나사산 형상에 따라 현저한 차이가 있었으며, v-자형 나사산 경우가 가장 낮았고, square 형의 경우가 가장 높았다. 나사산 차이가 인접골 응력에 미치는 영향은 나사산 첨부 보다는 기저부에 인접한 위치에서 더 현저하였다. 결론: 임플란트 식립응력을 낮추어 골융합에 유리한 환경을 조성하는데는 나사산 첨부가 상대적으로 날카로운 v-자형 나사산이 유리하다.

• 구강회복응용과학지
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• 제22권1호
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• pp.55-74
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• 2006

The external contour of an implant can have significant effects on the load transfer characteristics and may result in different bone failure rates for different implant system. The purpose of this study was to investigate the effects of crest module shape and occlusal load direction on bone failure modes of five commercially available dental implant systems. Five different implant systems with internal connection; ITI (Model 1), Astra (Model 2), Bicon (Model 3), Friadent (Model 4), and Paragon (Model 5), comparable in size, but different in thread profile and cest module shapes, were compared using the finite element method. Conclusively, in the internal connection system of the implant-abutment connection methods, the stress-induced pattern at the supporting bone according to the abutment connection form had differenence among them, and implants with narrowing crestal module cross-sections at the top of the cortical bone created more favorable load transfer characteristics in this region. But it is considered that the future study is necessary about how this difference in the magnitude of the stress have an effect on the practical clinic.

• Journal of Periodontal and Implant Science
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• 제29권1호
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• pp.209-231
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• 1999

Even though titanium(Ti) and its alloys are the most used dental implant materials, there are some problems that Ti wears easily and interferes normal osteogenesis due to the metal ions. Ti coated with bioactive ceramics such as hydroxyapatite has also such problems as the exfoliation or resorption of the coated layer, Recent studies on implant materials have been proceeding to improve physical properties of the implant substrate and biocompatibility of the implant surfaces. The purpose of the present study was to examine the physical property and bone tissue compatibility of bioinert nitrides ion plated Ti, Button type specimens(14mm in diameter, 2.32rrun in height) for the abrasion test and cytotoxicity test and thread type implants(3.75mm in diameter, 6mm in length) for the animal experiments were made from Ti(grade 2) and 316LVM stainless steel. Ti specimens were ion plated with TiN, ZrN by the low temperature arc vapor deposition, and the depth profile of the TiN/Ti, ZrN/Ti ion plated surface was examined by Auger Electron Spectroscopy. Three kind of button type specimens .of TiN/Ti, ZrN/Ti and Ti were used for abrasion test, and HEPAlClC7 cells and CCD cells were cultivated for 4 days with the specimens for cytotoxicity test. Thread type implants of TiN/Ti, ZrN/Ti, Ti, 316LVM were implanted on the femur of 6 adult dogs weighing 10kg-13kg. Two dogs were sacrified for histological examination after 45 days and 90 days, and four dogs were sacrified for the removal torque test of the implant') after 90 days. The removal torque force was measured by Autograph (Shimadzu Co., AGS-1000D series, Japan). Abrasion resistance of TiN/Ti was the highest, and that of ZrN/Ti and Ti were followed. The bioinert nitride ion plated Ti had much better abrasion resistance, compared with Ti, In the cytotoxicity test, the number of both cells were increased in all specimens, and there were no significant difference in cytotoxic reaction among all groups (p>0.1), In histological examination, 316LVM showed the soft tissue engagement in interface between the implant and bone, but the other materials after 45 days noted immature new bone formation in the medullary portion along the implant surface, and those after 90 days showed implant support by new bone formation in both the cortical and the medullary portion, The removal torque force of Tilv/Ti showed significantly higher than that of Ti(p(O,05). The difference in removal torque force between TiN/Ti and ZrN/Ti was not significant(p>0.05), and that of 316LVM was lowest among all groups(p<0.05). These results suggest that bioinert nitrides ion plated Ti can resolve the existing problems of Ti and bioactive ceramics, and it may be clinically applicable to human.