Biomedical subjects

Li-hui Tang

Publications and source records attributed to Li-hui Tang.

3 recordsLinked to original sources

PubMed2006

[The influence of nanometer inorganic filling carrying silver on the properties of composite resin].

PURPOSE: To observe the mechanical performance's effects of nanometer inorganic filling carrying silver on the properties of composite resin and find the perfect dose of the mixture. METHODS: The resin was mixed with inorganic filling whose doses were 0.5%, 1.0%, 1.5% and 2.0%, and then the compressive strength, flexure strength and wear-resistance were measured in the five groups. One-way ANOVA and Student's t test were used for statistical analysis in SPSS 10.0. RESULTS: The results showed that in the compressive strength tests, the 1.5% dose was perfect which was (264.93+/-12.48) MPa (P>0.05) and the 2.0% dose was bad which was (94.54+/-17.42) MPa (P<0.01); in the flexure strength tests, 0.5%, 1.0% and 1.5% dose didn't change significantly which were (86.25+/-12.76) MPa, (99.49+/-16.47) MPa and (108.69+/-10.35) MPa (P>0.05) respectively, and 2.0% dose went down significantly which was (79.79+/-8.10) MPa (P<0.01); in the wear-resistance tests, 1.5% and 2.0% worked very well which were (2.73+/-0.53) MPa (P<0.05), (2.70+/-1.25) MPa (P<0.01) respectively. CONCLUSION: Nanometer inorganic filling had no significant influence on the composite resin, and 1.5% dose of nanometer inorganic filling is perfect for the resin's mechanical properties.

Composite Resins↗

PubMed2005

[The study on fabrication of dental restoration using PMMA-ZrO2 composites via CAD/CAM].

OBJECTIVE: To obtain dental restorations by machining PMMA-ZrO2 organic-inorganic composites with the dental CAD/CAM system. METHODS: Partially sintered Zirconia compacts (PSZC) were prepared via isostatic pressing and partially sintering, with Zirconia nanopowder as raw materials. PMMA-Zirconia organic-inorganic composites were prepared by vacuum infiltrating the prepolymerized MMA into the PSZC, followed by in-situ polymerization. The mechanical properties and machinability of composites were studied. The composites were machined on the dental CAD/CAM system to obtain dental restoration. RESULTS: At 71.44% TD of PSZC, the composite had a 3-point bending strength of (202.56 +/- 3.09) MPa, fracture toughness of (4.30 +/- 0.16) MPa.m(1/2), elasticity modulus of (58.71 +/- 1.98) GPa, and Vickers hardness of (3.82 +/- 0.34) GPa, respectively. A premolar crown was fabricated by CAD/CAM system in 16 mins, and was verisimilitude, without any cracks. CONCLUSIONS: The composite at 71.44% TD of PSZC has good mechanical properties and dental restorations can be manufactured by PMMA-Zirconia composites via dental CAD/CAM system.

Computer-Aided Design↗

PubMed2003

[A study of injectable autogenous tissue-engineered bone].

OBJECTIVE: To investigate the utilization of carrier for delivering osteoblasts and creating autogenous bone tissue in ectopic site of animal via injection. METHODS: Bone marrow cells harvested from iliac bone of New Zealand rabbits were induced to differentiate into marrow stromal osteoblasts. The osteoblasts were mixed with 1.5% alginate sodium solution to generate osteoblasts/alginate composites with final cellular density of 4 x 10(9)/L. Calcium chloride was used as cross-linking agent to gel aqueous alginate solution. The marrow stromal osteoblasts/alginate composites were injected into the dorsal subcutaneous tissue of rabbits with autogenous cells transplantation. The samples were examined with X-ray and histological analysis. RESULTS: Four, eight and twelve weeks after injection, the hard knobbles were easily palpated under the dorsal skin of animals. On X-ray photograph the samples showed calcified image with more density than surrounding soft tissue, new bone formation was observed in the osteoblasts/alginate composites in histological analysis. The osteogenesis was in association with regenerated hematopoietic bone marrow. CONCLUSIONS: These results demonstrate that new bone tissue could be created through the injection of alginate sodium treated with autogenous marrow stromal osteoblasts.

Alginates↗