Biomedical subjects

Chun-Cheng Chen

Publications and source records attributed to Chun-Cheng Chen.

3 recordsLinked to original sources

PubMed2006

Improving the initial biocompatibility of a titanium surface using an Er,Cr:YSGG laser-powered hydrokinetic system.

OBJECTIVES: This study was designed to improve the initial biocompatibility of titanium (Ti) using an Er,Cr:YSGG-powered hydrokinetic system. METHODS: The Er,Cr:YSGG-powered hydrokinetic system with different laser energy densities, 125 and 190 J/cm(2), were applied to the Ti substrate. Human osteosarcoma U2-OS cells were used. The difference in the attached cell number between 3- and 1-days cell culture was calculated and defined as the initial cell proliferation index (CPI). The initial CPI was statistically analyzed using one-way analysis of variance with the factor of applied laser energy density. The surface spreading morphology of the attached cells after 1 day incubation was observed using a field-emission scanning electron microscope. RESULTS: The Er,Cr:YSGG laser-treated Ti had a higher (1.2-1.3 times) initial CPI (P<0.001) and better cell spreading morphology than the untreated Ti. Treating the Ti with higher Er,Cr:YSGG laser energy did not significantly improve the CPI and cell spreading morphology. SIGNIFICANCE: The initial biocompatibility of the Ti surface could be improved using an Er,Cr:YSGG laser-powered hydrokinetic system.

Analysis of Variance↗

PubMed2006

Characterization of functionally graded hydroxyapatite/titanium composite coatings plasma-sprayed on Ti alloys.

Bioceramic coatings like hydroxyapatite (HA) have shown promising bioactive properties in load-bearing implant applications. The aim of this work is to deposit functionally graded HA/Ti layers consisting of an underlying Ti bond coat, the alternating layer, and an HA top-layer on Ti6Al4V substrates using plasma spray to improve the coating-substrate interface properties. The alternating layers were created by means of changing the feeding rate and input power of Ti and HA powders, which gradually decrease Ti content with increasing depth from the Ti bond-coat. The major consideration is to examine the stability of the graded coatings. Experimental results indicated that surface chemistry and morphology of the graded coatings were similar to those of monolithic HA coatings. The bond strength values of the as-sprayed graded coatings were much superior to those of monolithic HA coatings. The cyclic fatigue did have a statistically significant effect on bond strength of monolithic HA coatings, with a decrease of 23%. However, the graded coatings were able to survive 1 million cycles of loading in air without significantly reduced bond strength. The in vitro electrochemical measurement results also indicated that the graded coatings had a more beneficial and desired behavior than monolithic HA coatings after fatigue.

Alloys↗

PubMed2006

Effect of conditioners on bond durability of resin composite to Nd:YAP laser-irradiated dentin.

The aim of this study was to evaluate the effect of conditioners (sodium hypochlorite (NaOCl), Roth's ethylenediaminetetraacetic acid (EDTA), and phosphoric acid) on shear bond strength and morphology of Nd:YAP laser-irradiated dentin. In particular, the key focus was on the bond durability between resin composite and treated dentin after being subjected to thermocycling in artificial saliva between 5 degrees C and 55 degrees C. Results indicated that the application of phosphoric acid to laser-irradiated dentin produced a bond strength comparable to those using NaOCl and EDTA. Further, dentinal tubules which were closed after laser irradiation opened following the treatment with conditioners. When subjected to 3,000 thermocycles, the mean shear strength of the samples treated by the three conditioners following laser irradiation ranged from 9.7 to 12.6 MPa with a reduction of 25-33%--a reduction rate lower than that obtained using acid etching alone (50%). Among the three conditioners tested, only phosphoric acid treatment demonstrated an enhanced effect on bond durability of laser-irradiated dentin.

Acrylic Resins↗