The Effect of Heat Treatment on Physical, Chemical and Structural Properties of Calcium Sulfate Based Scaffolds

3d printed calcium sulfate (cs) is a promising material for on custom bonesubstitutes. since it dissolves easily in body fluids, manufactured samples require to beingimproved to reduce solubility. the main aim of this study was reducing the dissolubility of csbased samples by using sintering and investigating the effect of heat treatment on theirphysical, chemical and structural properties. to observe the effect of heat treatment onsamples, contact angles were measured, x‐ray diffraction analysis (xrd) was performed, andscanning electron microscope (sem) micrographs were captured before and after the sinteringprocess, and the results were compared. furthermore, sintered and non‐sintered samples weresoaked in phosphate buffered saline (pbs) to observe the impact of sintering on the solubility ofthe material. also, three different pore sized scaffolds were manufactured to test the limits ofthe 3d printer for manufacturing of scaffolds with open pores. sintering process results in avolume reduction and according to sem results, cs grains were fused together after heattreatment. although non‐sintered cs sample starts to dissolve in high rate and nearly 1/3 of the sample was at the bottom of the glass in a matter of minutes, sintering creates more rigidstructure and there were not visible dissolution in pbs at the end of a week. the contact angleof samples cannot be measured, so it can be concluded that 3d printed material showed asuper‐hydrophilic property. xrd diagram suggested that there is not any new phase created inthe printing and sintering processes except related hydrates of cs. as a result of the 3d printing,500 μm, 750 μm and 1000 μm pore sized scaffolds were manufactured, successfully. however, itwas seen that 500 μm pores could not be open by using depowdering after the printing process.