Effect of Particle Size Ratios on the Physical and Chemical Properties of Surgical‐Grade Calcium Sulfate Hemihydrate

Abstract

Objectives To analyze the optimum particle size or formula ratio of surgical‐grade calcium sulfate (CS) for appropriate compressive strength, setting time, and vitro degradation rate. Methods Three types of calcium sulfate hemihydrate (CSH) particles with diameters of 0–37.5 μm, 37.5–75 μm, and >75 μm were screened. Based on formulation ratio of different particles, this topic is divided into 10 groups by the unconstrained third‐order simplex lattice mixing design scheme in formula design experiment. The optimum formulation ratio of particle diameter for compressive strength, solidification time, and degradation rate in vitro was analyzed. Results When the percentage of the particle diameter of CS with 0–37.5 μm, 37.5–75 μm and >75 μm are 55.0%, 17.4%, and 27.6% respectively, the compressive strength of the test sample is the highest, which is 14.16 MPa. When the percentage of the particle diameter of CS with 0–37.5 μm, 37.5–75 μm, and >75 μm are 0.00%, 0.00%, and 100.00% respectively, the initial setting time of the sample is the longest, which is 410.0 s. When the percentage of the particle diameter of CS with 0–37.5 μm, 37.5–75 μm, and >75 μm are 0.00%, 0.00%, and 100.00% respectively, the final setting time of the sample is the largest, and the final setting time of the sample is 460.00 s. When the percentage of the particle diameter of CS with 0–37.5 μm, 37.5–75 μm, and >75 μm are 0.00%, 0.00%, and 100.00% respectively, the degradation rate of the sample in vitro is the slowest, which is 18.8%. Conclusion The morphological structure of surgical‐grade CS can affect compressive strength, setting time, and in vitro degradation rate. Surgical CS should be prepared based on different uses.

Current Use of Calcium Sulfate Bone Grafts

“…In a study by Hu et al, the authors studied the effect of particle size on the biophysical properties of CS bone grafts. 64 This group found that grafts comprised of smaller sized CS particles demonstrated increased compressive strength and a slower in vitro degradation rate. In this regard, various nano-sized bone grafting materials have received FDA approval in the past decade for osseous corrective surgeries.…”

Simultaneous effect of Na2EDTA on the phase transformation and morphology evolution during the transformation of gypsum into α-calcium sulfate hemihydrate

“…[2][3][4] As for the utilization of a-HH, in general, the larger the particle size and the higher the crystallinity, the better the performance of a-HH. [5][6][7] It is reported that the short columnar a-HH is an ideal crystal with high mechanical strength and good performance, [8][9][10][11] and additives are usually applied to modulate the crystal morphology of a-HH. In order to obtain short columnar a-HH, some special additives, such as citric acid, ethylenediamine tetracetic acid (EDTA), malic acid and aluminum chloride are used.…”

Selective Crystal Growth Regulation by Chiral α-Hydroxycarboxylic Acids Improves the Strength and Toughness of Calcium Sulfate Cements

“…Calcium sulfates are among the most used materials, and their applications include construction, food additives’ , targeted drug delivery, − and plaster casts for medical and dental applications. , They are also used as resorbable bone repair materials. ,− …”