• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.7.1-7.1
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• 2009

The use of Duplex stainless steel as a thermo-implant categorizes into two clinical applications: hyperthermia and thermal ablation or destruction. The goal of hyperthermia is to destroy the heat-sensitive abnormal cells and minimize normal cell death maintaining heat between $42^{\circ}C$ and $46^{\circ}C$. Thermal ablation takes place when the local tissue temperature increases greater than $46^{\circ}C$. This elevated temperature denatures protein irreversibly resulting cellular death. The author introduced several thermo-implants such as thermo-rod, thermo-stent, thermo-coil and thermoacupuncture-needle. Those thermo-implants are made of duplex stainless steel which can produce regulated heat by itself within an induction magnetic field. Thermal ablation characteristics of the thermo-rod on tumor hyperthermia depend on configurations of the thermo-rods and the magnitude of the induction magnetic strength. The exothermic properties of the thermo-implants can be characterized using the calorimetric test and the heat affected zone(HAZ) analyses in vitro. Thermal radiation studies using thermo-coils and thermo-stents show the capability of the occlusion of animal blood vessels and inhibiting the proliferation of the abnormal smooth muscle cell growth and inflammatory cell reactions maintaining the heat between $42^{\circ}C$ and $46^{\circ}C$ minimizing a normal cell death in the study on external iliac artery of the New Zealand White (NZW) rabbit. Thermal stimulation study using thermo-acupuncture needles suggests the potential applications of the automated acupunctural therapies.

• The Journal of Advanced Prosthodontics
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• v.6 no.5
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• pp.346-350
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• 2014

PURPOSE. Impact forces in implant supported FDP (fixed dental prosthesis) are higher than that of tooth supported FDPs and the compositions used in frameworks also has a paramount role for biomechanical reasons. The aim of this study was to evaluate the flexural strength of two different zirconia frameworks. MATERIALS AND METHODS. Two implant abutments with 3.8 mm and 4.5 mm platform were used as premolar and molar. They were mounted vertically in an acrylic resin block. A model with steel retainers and removable abutments was fabricated by milling machine; and 10 FDP frameworks were fabricated for each Biodenta and Cercon systems. All samples were thermo-cycled for 2000 times in $5-55^{\circ}C$ temperature and embedded in $37^{\circ}C$ artificial saliva for one week. The flexural test was done by a rod with 2 mm ending diameter which was applied to the multi-electromechanical machine. The force was inserted until observing fracture. The collected data were analyzed with SPSS software ver.15, using Weibull modulus and independent t-test with the level of significance at ${\alpha}=.05$. RESULTS. The mean load bearing capacity values were higher in Biodenta but with no significant differences (P>.05). The Biodenta frameworks showed higher load bearing capacity ($F_0=1700$) than Cercon frameworks ($F_0=1520$) but the reliability (m) was higher in Cercon (m=7.5). CONCLUSION. There was no significant difference between flexural strengths of both zirconia based framework systems; and both Biodenta and Cercon systems are capable to withstand biting force (even parafunctions) in posterior implant-supported bridges with no significant differences.