Setting solution concentration effect on properties of a TTCP/DCPA-derived calcium phosphate cement.
The present work was to investigate the effects of concentration of (NH(4))(2)HPO(4) (diammonium hydrogen phosphate) setting solution on properties of a tetracalcium phosphate (TTCP)/dicalcium phosphate anhydrous (DCPA)--derived calcium phosphate cement. Experimental results indicated that working/setting time of the cement paste decreased with increasing (NH(4))(2)HPO(4) concentration of the setting solution. After being immersed in Hanks' solution for 1 day or longer, the XRD intensities of initial TTCP and DCPA phases largely decreased, while apatite phase became dominant. More residual TTCP phase was observed in the 1 day-immersed cement prepared from higher concentration setting solutions. Compressive strength of the cement immersed for 1 day was consistently higher than that immersed for 30 min or 7 days. After being immersed for 1 day, the average CS value reached a maximal value (59 MPa) as (NH(4))(2)HPO(4) concentration was increased to 0.6 M, beyond that the cement strength decreased and maintained in a relatively high range of 47-54 MPa. Cells incubated with conditioned medium of Al(2)O(3) powder and with blank medium exhibited similar average viability values (0.80 and 0.78, respectively). The OD value with extractions of cement decreased with increasing (NH(4))(2)HPO(4) concentration of the setting solution. The average 0.25, 0.5 and 0.6 M--OD values were 0.78, 0.67 and 0.66, respectively. When setting solution concentration was greater than 0.6 M, the OD value sharply declined to 0.47.
Department of Materials Science and Engineering, National Cheng-Kung University, No. 1 University Road, 70101, Tainan, Taiwan, ROC.
Chang-Keng
CK
Chen
Chien-Ping
CP
Ju
Jiin-Huey Chern
JH
Lin
D000818:Animals; D001843:Bone Cements / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D002130:Calcium Phosphates / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002484:Cementation / Q000379:methods; D011232:Chemical Precipitation / Q000187:drug effects; D019245:Compressive Strength / Q000187:drug effects; D006244:Hardness / Q000187:drug effects; D008422:Materials Testing; D051379:Mice; D041681:NIH 3T3 Cells; D009994:Osmolar Concentration; D044367:Phase Transition / Q000187:drug effects; D012996:Solutions / Q000737:chemistry* / Q000494:pharmacology; D013997:Time Factors; D014961:X-Ray Diffraction
D001843:Bone Cements; D002130:Calcium Phosphates; D012996:Solutions; C485830:tetracalcium phosphate; C485829:calcium phosphate, dibasic, anhydrous