Calcium phosphate cement: in vitro and in vivo studies of the α-tricalcium phosphate-dicalcium phosphate dibasic-tetracalcium phosphate monoxide system

Abstract

In this paper, calcium phosphate cement consisting of ~-tricalcium phosphate (a-TCP), dicalcium phosphate dibasic (DCPD) and tetracalcium phosphate monoxide (TeCP) was investigated in vitro and in vivo. Measurements of compressive strength against soaking time in simulated body fluid (SBF) showed a rapid increase of the hardness for the first 7 days. The gained strength was retained up to 1 year and the maximal mean value was 94.7 (_+ 14.4)MPa. X-ray diffraction (XRD) and scanning electron microscopy (SEM) presented precipitates of hydroxyapatite (HA) after mixing, also after soaking in SBF and after implantation in rat subcutaneous tissues. However, the conversion to HA happened in different ways between in vitro and in vivo exposures. Histologic examinations showed that the cement causes the same reactions at the interface with surrounding soft tissues as HA. The authors consider the cement to be a promising material as a bone substitute, bone cement or dental material, however, further studies in a paste form and in bone tissue environments are necessary.

Eignung von Zementen auf Kalziumbasis

“…Dieser Vorteil ist gerade beim Einsatz am jüngeren Patienten von enormer Bedeutung. Die bisher untersuchten Kalziumphosphatzemente wurden den biomechanischen Anforderungen jedoch nicht gerecht und schnitten immer schlechter als PMMA ab [1,8,9].…”

Augmentation of Flat Bone Area Using Tetrapod-Shaped Artificial Bone in Rats

“…Hydroxyapatite (HA) granules [1][2][3] andtricalcium phosphate paste (P ) [4][5][6] are widely used as bone substitutes in patients with fractures, bone defects or absorption of the alveolar ridge 7,8) . On the other hand, animal studies have led to the developments of new techniques, including autogenous bone onlay grafting [9][10][11][12] and artificial bone block 3,6,[13][14][15][16][17][18] .…”

Bone cements based on ground β-tricalcium phosphate with sufficient compressive strengths and short hardening time

“…Paste-like calcium phosphate cements thus developed may be classified into two groups on the basis of the type of hardening reaction: i) acidbase reaction among calcium phosphates to form apatite or calcium hydrogenphosphate dihydrate [CaHPO 4 3) A representative example of the latter type is hardening caused by hydrolysis of ¡-tricalcium phosphate [Ca 3 (PO 4 ) 2 ] (¡-TCP). 4), 5) Recently, amorphous ¢-TCP ground with a ball mill has been found to be subject to hydrolysis.…”

“…4), 5) Recently, amorphous ¢-TCP ground with a ball mill has been found to be subject to hydrolysis. 6) We reported that H 2 Oincorporated ¢-TCP ground with a mortar grinder is easily hydrolyzed 7), 8) and hardened when mixed with a 2.5 wt % disodium hydrogenphosphate [Na 2 HPO 4 ] aqueous solution.…”