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Advanced Dental Care 2018
Dentistry and Craniofacial Research
ISSN: 2576-392X
Page 23
October 08-09, 2018
Moscow, Russia
26
th
International Conference on
Advanced Dental Care
T
he bone graftingmaterialsmust have porous structure because
it induces the growth of blood vessels into the material.
Mooney et al. reported the method to produce porous structure
in PLGA scaffold by the expansion of CO
2
gas in high pressure
chamber. The CO
2
has some solubility in the PLGA. Thus, when
the high pressure of CO
2
is applied to the PLGA scaffold and
then released quickly, it becomes to expand in the PLGA matrix.
Resultantly, the pores are developed at the places where the gas
existed. However, the disadvantage of this method is that it is
also hard to connect between the pores. Thus, the salt leaching
method is combined together to make porous structure. However,
there has been no report to apply this method to make a porous
bioactive composite material. In this study, we prepared the PLGA/
calcium silicate composite by the solvent casting method and
then a gradient pore structure was introduced using the expansion
of CO
2
gas in a high pressure chamber. The 70Poly(40Lactic-co-
60Glycoric Acid)/30(75SiO
2
-25CaO) composite, which have a
gradient pore structure, was newly prepared by the expansion
of carbon dioxide gas in the PLGA matrix. The bioactive 75SiO
2
-
25CaO (in wt.%) particles were made by a sol-gel method from
tetraethyl orthosilicate and calcium nitrate tetrahydrate under
acidic condition followed by the heat treatment at 700°C for 1 h.
The 70Poly (40Lactic-co-60Glycoric Acid)/30(75SiO
2
-25CaO)
composite was then prepared by a solvent casting. The composite
was loaded into the high pressure chamber and then CO
2
gas was
introduced achieving a final pressure of 15 MPa. After 3 days,
the gas was released quickly and the gradient pore structure
was developed. The samples were observed by FE-SEM and its
bioactivity was tested in SBF.
Biography
SangHoon Rhee has completed his PhD at the age of 34 years from Seoul Na-
tional University and postdoctoral studies from National Institute of Materials
Science. He is the professor of School of Dentistry, Seoul National University.
He has published more than 70 papers in reputed journals and has been serv-
ing as an editorial board member of International Journal of Biomaterials and
Journal of Biotechnology and Biomaterials.
rhee1213@snu.ac.krPreparation of a bioactive and degradable
70poly (40lactic-co-60glycoric acid)/30(75SiO
2
-
25CaO) composite with dual pore structure
Sang Hoon Rhee
1
, Suk Young Kim
2
and In Hwan Song
2
1
Seoul National University, Republic of South Korea
2
Yeungnam University, Republic of South Korea
Sang Hoon Rhee et al., Dent Craniofac Res 2018, Volume 3
DOI: 10.21767/2576-392X-C4-012