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Publications (4)8.4 Total impact

  • Article: The effects of early osseointegration in different implant sites in rabbit tibias.
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    ABSTRACT: The aim of this study was to evaluate the early osseointegration of implants with the same surface treatment in different implant sites in rabbit tibias after 4 weeks. A total of 42 acid-etched implants were implanted in three different sites in the tibia: group A was 2.08 ± 0.18 mm below epiphyseal line; group B was 7.00 ± 0.61 mm below the epiphyseal line; group C was 13.01 ± 1.26 mm below the epiphyseal line. After 4 weeks, the average bone-to-implant contact (BIC) values were as follows: group A, 40.02 ± 4.82 %; group B, 28.20 ± 5.41 %; group C, 20.76 ± 3.10 %. The BIC measurements yielded statistically significant differences among group A, group B and group C (P < 0.01); group A demonstrated the best osseointegration. In the present study, the different implantation sites in the selected 20-mm area demonstrated different early osseointegration; the sites located 7 ± 1.5 mm below the epiphyseal line were best suited for observing the effectiveness of early osseointegration among the three sites. The statistical results of the early osseointegration of implants are therefore affected by the location of the implant sites in this 20-mm area.
    Journal of Materials Science Materials in Medicine 02/2013; · 2.32 Impact Factor
  • Article: Effects of storage methods on time-related changes of titanium surface properties and cellular response.
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    ABSTRACT: Titanium implants are sold in the market as storable medical devices. All the implants have a certain shelf life during which they maintain their sterility, but variations of the surface properties through this duration have not been subject to a comprehensive assessment. The aim of this study was to investigate the effects of storage methods on time-related changes of titanium surface properties. Acid-etched titanium discs (Sa = 0.82 µm) were placed in a sealed container (tradition method) or submerged in the ddH(2)O/NaCl solution (0.15 mol L(-1))/CaCl(2) solution (0.15 mol L(-1)), and new titanium discs were used as a control group. SEM and optical profiler showed that surface morphology and roughness did not change within different groups, but the XPS analysis confirmed that the surface chemistry altered by different storage protocols as the storage duration increased, and the contact angle also varied with storage methods. The storage method also affected the protein adsorption capacity and cellular response on the titanium surface. All titanium discs stored in the solution maintained their excellent bioactivity even after four weeks storage time, but titanium discs stored in a traditional manner decreased substantially in an age-dependent manner. Much effort is needed to improve the storage methods in order to maintain the bioactivity of a titanium dental implant.
    Biomedical Materials 07/2012; 7(5):055002. · 2.16 Impact Factor
  • Article: Surface characteristics and biocompatibility of sandblasted and acid-etched titanium surface modified by ultraviolet irradiation: an in vitro study.
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    ABSTRACT: Sandblasting with large grit and acid-etching (SLA) treatment is considered to be a reliable modification to achieve excellent titanium surface. However, contamination of hydrocarbons would make SLA surface hydrophobic and influence its bioactivity. Thus, appropriate methods of preservation or further treatments could be used for improvement. In present study, preservation in deionized water (dH(2)O) and ultraviolet (UV) irradiation were, respectively, applied to achieve modSLA and UV-SLA surfaces. Surface characteristics were assessed by scanning electron microscopy, optical profilometer and x-ray photoelectron spectroscopy as well as wettability by optical contact angle analyzer. Additionally, biocompatibility was evaluated by the response to osteoblast-like MG63 cells. Prevented from further contamination, modSLA surface with fewer hydrocarbons (25.31%) remained hydrophilic and showed better affinity to mineralization of MG63 cells than hydrophobic polluted SLA surface (p < 0.01). Furthermore, with the lowest content of hydrocarbons (14.26%) and super-hydrophilicity, UV-SLA surface, which had the hydrocarbons effectively decomposed by photocatalysis and meanwhile acquired abundant hydroxyl groups, had most greatly promoted the attachment, proliferation, differentiation, and mineralization of MG63 cells (p < 0.05). Therefore, hydrocarbons were found to be an important influencing factor to compatibility of biomaterials. In addition, UV irradiation was recognized as a trustworthy method for surface cleaning without change of topography and roughness and could ever lead to greater biocompatibility of sandblasted and acid-etched titanium surface.
    Journal of Biomedical Materials Research Part B Applied Biomaterials 06/2012; 100(6):1587-98. · 2.15 Impact Factor
  • Article: Bone response to a pure titanium implant surface modified by laser etching and microarc oxidation.
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    ABSTRACT: To compare the bone responses to a pure titanium machined implant surface and one that has been modified by laser etching and microarc oxidation. Forty-eight threaded implants with a machined surface were manufactured from rods of commercially pure titanium. The control group consisted of 24 implants with a machined surface. The test group consisted of 24 machined-surface implants that were modified by laser etching and treated by microarc oxidation in an electrolyte solution containing Ca2+ and PO43- ions. The implants were analyzed by energy-dispersive x-ray and scanning electron microscopy. Next, the two types of implants were inserted in the tibiae of 12 New Zealand White rabbits; one of the two tibiae received two control implants and the opposite side received two test implants. After 2, 4, and 6 weeks, the rabbits were sacrificed. Prior to sacrifice, all rabbits were injected with fluorescent-labeled achromycin and calcein. Samples were cut and ground for histomorphologic observation, and the mineralization appositional rate and the osseointegration index were measured and analyzed. Proportional spacing craters were found with a diameter of 100 microm and a depth of 80 to 100 microm at intervals of 100 microm around the test surface, and a porous titanium dioxide coating on the surface with pores of 1 to 5 micro in diameter was also produced. Carbon, oxygen, calcium, and phosphonium were detected by electronic probe. The ratio of calcium to phosphonium was 1.418, and the crystal structure of x-ray diffractive patterns indicated pure anatase phases. Compared with the control samples, the mineralization ratio and the osseointegration index of the bone around the test implants were higher (P = .00). The porous titanium dioxide coating produced by laser etching and microarc oxidation treatment improved the bone response versus that seen around machined titanium implants and enhanced the bone formation rate. It was concluded that the surface chemistry and topography, either separately or together, play an important role in the bone response to implants.
    The International journal of oral & maxillofacial implants 25(1):130-6. · 1.78 Impact Factor