Muscle contractions then push the stool toward the rectum, and, by the time the stool reaches the rectum, most of the water has been absorbed, making the stool solid. When the colon's muscle contractions are slow or sluggish, the stool moves through the colon too slowly, resulting in too much water being absorbed.
The microparticulate allograft is a mixture of mineralized cortical bone particles of a standard combination of sizes between 100 and than 250 microns. This provides an optimal scaffold for delivering osteoinductive growth factors. This preparation has an appropriate 3-dimensional (3-D) structure
Irregular PVA is available as dry particles, with sizes ranging from 50 to 1,200 Âµm, which allows adequate selection of the particle size to fit various applications (PVA foam embolization particles). Typical PVA microparticles are made by grinding the plastic material on a file to produce particles of diverse sizes. The particles are then passed through sieves of differing sizes, and the appropriate particle sizes selected.