Development of a new calcium phosphate cement that contains sodium calcium phosphate.
A cement powder consisting of sodium calcium phosphate, Na3Ca6(PO4)5, in addition to tetracalcium phosphate and beta-tricalcium phosphate was prepared by pulverizing blocks of 4 wt% sodium-, 11 wt% carbonate-containing apatite samples that were heated at 1700 degrees C for 5 h. When mixed with 30 wt% malic acid or citric acid at a powder liquid ratio of 3:1, the cement set in 3 or 7 min at room temperature with compressive strength being around 52 or 27 MPa. In HeLa-cell cultures, the cement mixed with malic acid was less cytotoxic than the cement mixed with citric acid, which was far less cytotoxic than a commercial carboxylate cement used as a negative control, suggesting malic acid to be superior to citric acid as a liquid in this regard. Similar findings were also obtained with osteoclasts, of which culture experiments clearly suggested that the number of osteoclasts on the cement mixed with malic acid was significantly greater than that on the cement mixed with citric acid. Since osteoclastic response to substrates could be used as a maker in evaluating their bioresorbability associated with osteoclasts, the above finding may suggest that the cement that is to be mixed with malic acid would be more useful as bone substitutes.
Department of Dental Materials & Technology, School of Dentistry, Asahi University, Gifu, Japan. ytkdoi@dent.asahi-u.ac.jp
Y
Y
Doi
Y
Y
Shimizu
Y
Y
Moriwaki
M
M
Aga
H
H
Iwanaga
T
T
Shibutani
K
K
Yamamoto
Y
Y
Iwayama
D000818:Animals; D001843:Bone Cements / Q000138:chemical synthesis* / Q000737:chemistry* / Q000633:toxicity; D018786:Bone Substitutes / Q000138:chemical synthesis / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D019343:Citric Acid; D019245:Compressive Strength; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008293:Malates; D008422:Materials Testing; D010010:Osteoclasts / Q000187:drug effects; D011208:Powders; D011817:Rabbits; D014961:X-Ray Diffraction
D001843:Bone Cements; D018786:Bone Substitutes; D002130:Calcium Phosphates; D008293:Malates; D011208:Powders; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; D019343:Citric Acid; C485838:calcium phosphate, monobasic, anhydrous; C076375:rhenanite; C030298:malic acid; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous