Transformation from calcium sulfate to calcium phosphate in biological environment.

The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, especially for non-phosphate bioceramics. In the present study, strontium-doped calcium sulfate, (Ca,Sr)SO, was used to verify the feasibility of this measure. The (Ca,Sr)SO specimen was prepared by mixing 10% SrSO by weight with 90% CaSO·½HO powder by weight.

Cytotoxicity and cell response of preosteoblast in calcium sulfate-augmented PMMA bone cement.

Poly(methyl methacrylate) (PMMA) has been widely used in orthopedic applications, but bone ingrowth and toxic monomer release are drawback of this material. Particle reinforcement with osteoconductive substitute, such as calcium sulfate (CaSO), is one of the solutions used to modify PMMA bone cement. The current study investigated the mechanical, chemical and biological properties of CaSO-augmented bone cement.

Long-term in vitro degradation and in vivo evaluation of resorbable bioceramics.

An essential criterion for the selection of resorbable bioceramics is their ability to degrade inside human body within a reasonable time frame. Furthermore, if the bioceramic can release beneficial ions, such as strontium, as it degrades, recovery time might be shortened. The present study demonstrates that strontium-containing calcium sulfate (Sr,Ca)SO can fulfill these criteria.

Biphasic ceramic bone graft with biphasic degradation rates.

In this study, the characteristics of a novel biphasic bone graft are reported. The bone graft is a physical mixture of calcium sulfate (CS) and hydroxyapatite (HA). This biphasic bone graft was prepared by sintering at 1100 °C.

A head-to-head comparison of the degradation rate of resorbable bioceramics.

Resorbable bioceramics offer advantages in healing bone defects due to their degradation capability. Degradation rates differ significantly from one bioceramic to another; nevertheless, the degradation rate should match the growth rate of new bone. In the present study, a head-to-head comparison of the degradation rate of calcium sulfate and tricalcium phosphate is conducted.

Manipulation of the degradation behavior of calcium sulfate by the addition of bioglass.

A bioactive calcium sulfate/glass composite was prepared using a sintering technique, and Ca-P-Si glass particles were prepared by spray pyrolysis. The glass exhibited bioactivity in terms of its ability to form apatite in a simulated body fluid. The glass was transformed into two crystallized phases, i.

Improving biodegradation behavior of calcium sulfate bone graft tablet by using water vapor treatment.

The biodegradation rate of calcium sulfate hemihydrate (CSH) tablets is extremely rapid. This study adopts a water vapor treatment to modify the surface structure of a CSH tablet. After the treatment, a small amount of calcium sulfate dihydrate (CSD) forms on the surface; the porosity near the surface region decreases, consequently enhancing tablet strength and surface hardness.

Porous calcium sulfate ceramics with tunable degradation rate.

It would be ideal if bone substitutes could be absorbed by the human body upon the formation of new bone. Although calcium sulfate is absorbable, its biodegradation rate is very fast. Fortunately, this rate can be reduced significantly through various sintering techniques.