• 대한치과보철학회지
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• 제33권3호
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• pp.517-538
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• 1995

Dental implantation is a method restoring missing teeth, especially in the case of severely resorbed edentulous patient. But the direct contact between bone and implant surface, induces stress concentration to the bone and eventually becomes a cause. The purpose of this study was to compare the stress distribution patterns between following two cylindrical implant models. One group has implant apex located in the inferior cortical bone and the other in the cancellous bone. Anterior edentulous mandible was modeled with two dimensional 953,878 nodes, 995,918 elements and compared the deflection and stress distribution under the 70 N,4 load cases for 26 models having variant mandibular height and length. The result were as follows; 1. The stress concentration was more affected by the height of the mandible than implant length. 2. Bicortication mitigates the stress of upper cortical and cancellous bone area at the same height of the mandible 3. Perforation of the inferior mandibular cortex significant stress concentration. 4. Stud type porstheses induced less stress concentration to the cortical and cancellous bone than bar type prostheses. 5. Stress of implant apex for stud type was larger than that of bar type.

• Restorative Dentistry and Endodontics
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• 제25권1호
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• pp.85-90
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• 2000

For more esthetic treatments the use of composite in molar areas are increasing. But polymerzation shrinkage that cause marginal leakage and cuspal deflection has been the problems of composites. The purpose of this study is to compare the effect of low intensity curing and polishing period on marginal leakage. Cavities were prepared on the buccal or lingual surface of forty five sound extracted human teeth and etching, application of bonding agent and filling of composite was done. Group 1 was light cured at intensity of 600$mW/cm^2$ for 41 seconds and polished. Group 2 was light cured at intensity of 300$mW/cm^2$ for 2 seconds and polished and after polishing it was light cured for 40 seconds at 600$mW/cm^2$. Group 3 was light cured at intensity of 300$mW/cm^2$ for 2 seconds and waited for 5 minutes and after curing at 600$mW/cm^2$ for 40 seconds polishing was done. The specimens were thermocycled at $5^{\circ}C$ and $55^{\circ}C$ for 1000 cycles and immersed in 2% methylene blue solution for 24 hours. Composite-tooth interface was examined under stereobinocular microscope for dye penetration. The results were as follows : 1. Group which were cured at low intensity and polished after curing at high intensity showed less marginal leakage than group which were cured at high intensity for 41 seconds(p<0.05). 2. Marginal leakage between group which were cured at low intensity and polished immediately and group which were cured at high intensity for 41 second were not significantly different. Light curing at low intensity can reduce marginal leakage but polishing immediately after curing at low intensity for short time can affect marginal leakage.

• 대한치과보철학회지
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• 제60권1호
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• pp.110-118
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• 2022

다수의 치아 상실은 교합의 부조화를 일으키며, 수직고경 상실과 하악 운동의 변위를 유발할 수 있기 때문에 중심위에서 적절한 수직 고경과 교합을 재형성하는 것이 중요한 치료 목표가 될 수 있다. 한편, 임플란트 보조 국소의치는 국소의치의 유지, 지지 및 안정을 증가시켜 환자의 만족도를 높이기 때문에 최근에 자주 사용되는 임상 술식이다. 본 증례는 편측 구치부 및 전치부 지지의 소실로 편측 교합면간 거리가 소실된 환자에서 치료 의치를 제작하고 기존에 식립된 양측의 임플란트를 지대치로 이용한 임플란트 보조 국소의치를 제작하였고 양호한 임상 결과를 확인하였기에 이를 보고하고자 한다.