Deriving fast setting properties of tetracalcium phosphate/dicalcium phosphate anhydrous bone cement with nanocrystallites on the reactant surfaces.
OBJECTIVE
This study attempts to reveal how nanocrystallites on the ceramic surfaces of non-dispersive calcium phosphate cement (nd-CPC) participate in setting processes as compared with conventional CPC (c-CPC).


METHODS
The compositions and morphologies of CPC during the early setting reactions were studied with X-ray diffraction and a scanning transmission electron microscope equipped with an energy dispersive spectroscopy system. The pH values and dispersive properties of CPC during the early setting reactions were investigated as well as the compressive strength of nd-CPC after 24h of immersion with varying liquid to powder ratios.


RESULTS
The mechanical strength of nd-CPC was approximately 60MPa after a 24h immersion in simulate body solution with a P/L ratio between 3.3 and 4.2g/mL. The nanocrystallites on the particle surfaces of nd-CPC were shown to grow rapidly and provided interlocking sites that allowed rapid development of the apatite phase in the cement, and were also shown to be non-dispersive in solution as determined by an injection test of c-CPC.


CONCLUSIONS
The interlocking particles produced by whisker growth on the ceramic particles or new crystallites formed between the ceramic particles caused the cement to be non-dispersive in solution. The particles of reactants with nanocrystallites on surfaces also gave this cement the ability to be shaped easily as a paste during an operation or to be injected into a cavity.
Wang
Jen-Chyan
JC
School of Dentistry, Kaohsiung Medical University, 807 Kaohsiung City, Taiwan, ROC.
Ko
Chia-Ling
CL
Hung
Chun-Cheng
CC
Tyan
Yu-Chang
YC
Lai
Chern-Hsiung
CH
Chen
Wen-Cheng
WC
Wang
Chih-Kuang
CK
D001031:Apatites / Q000737:chemistry; D001843:Bone Cements / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D055598:Chemical Phenomena; D019245:Compressive Strength; D003460:Crystallization; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007101:Immersion; D008422:Materials Testing; D017348:Microscopy, Electron, Scanning Transmission; D053758:Nanoparticles / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors; D014961:X-Ray Diffraction
D001031:Apatites; D001843:Bone Cements; D002130:Calcium Phosphates; C485830:tetracalcium phosphate; C485829:calcium phosphate, dibasic, anhydrous