Article

Development of Bioactive Sol-Gel Material Template for In Vitro and In Vivo Synthesis of Bone Material

Journal of Sol-Gel Science and Technology (impact factor: 1.63). 11/2000; 19(1):441-445. DOI:10.1023/A:1008799513932 pp.441-445

ABSTRACT A novel porous material produced via sol gel process is disclosed which is osteoinductive and biodegradable. Due to the fact that high temperatures are avoided during the production process, the degree of crystallinity is very low and the packing of the crystallites is relatively loose. These are important parameters for the biodegradation properties.Nanoporous silica gel is contained to the support of strength. The low degree of crystallinity and the high degree of porosity (50–70%, pores in the range of few microns) make the material resorbable. A second type of pores designed in the range of few millimetres supports the bone ingrowth.An in vitro formation of bone tissue is shown when the material is exposed to tissue culture medium and inoculated with human osteoblastic cells. Animal tests show the formation of new bone tissue and first steps of biodegradation.

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    Article: Macroscopical, histological, and morphometric studies of porous bone-replacement materials in minipigs 8 months after implantation.
    Kai-Olaf Henkel, Thomas Gerber, Solvig Lenz, Karsten K H Gundlach, Volker Bienengräber
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    ABSTRACT: The aim of this investigation was to test the induction of bone formation and biodegradation of different biomaterials based on calcium phosphate (CaP). Up to now, hydroxyapatite and beta-tricalcium phosphate ceramics have routinely been sintered at temperatures of 1300 degrees C. The new CaP biomaterials tested are fabricated by a sol-gel process at only 700 degrees C. Critical-size defects (>5 cm(3)) in the mandible of 15 adult Goettingen minipigs were filled with 1 of the 2 new types of CaP biomaterials, or with 1 of 2 well-known old-type ceramics, or with a gelatin sponge (in the control group). Macroscopical, histological, and morphometric examination of the former defect areas were made 8 months postoperatively. Eight months after implantation of the new CaP biomaterials, complete bone formation was observed in the defect area, and at the same time, the foreign material was resorbed almost completely. After implantation of the classical types of ceramics, only incomplete bone formation and a lesser resorption rate of the foreign bodies were noted. The difference in the bone formation rate was significant: more than 93% for the new CaP biomaterials versus less than 58% for the classical types of ceramics (P < 0.01). The biological behavior of the new CaP biomaterials was better than that of the old-type sintered ceramic bone-grafting materials. These new CaP matrices are suitable for filling bone defects and are of interest for dentists, including implantologists, craniomaxillofacial and orthopedic surgeons, as well as traumatologists.
    Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 12/2006; 102(5):606-13. · 1.50 Impact Factor
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    Article: Neuartiges Knochenaufbaumaterial auf Kalziumphosphatbasis
    K.-O. Henkel, Th. Gerber, W. Dietrich, V. Bienengräber
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    Mund- Kiefer- und Gesichtschirurgie 04/2012; 8(5):277-281.
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    Shahram Ghanaati, Carina Orth, Mike Barbeck, Ines Willershausen, Benjamin W Thimm, Patrick Booms, Stefan Stübinger, Constantin Landes, Robert Anton Sader, Charles James Kirkpatrick
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Keywords

Animal tests
 
biodegradable
 
biodegradation properties.Nanoporous silica gel
 
bone ingrowth.An
 
bone tissue
 
crystallinity
 
first steps
 
inoculated
 
low degree
 
microns
 
millimetres
 
new bone tissue
 
novel porous material
 
pores
 
temperatures
 
tissue culture medium
 
vitro formation
 

Th Gerber