Abstract
Silico-doped hydroxyapatite is currently being investigated as a promising biocompatible material for use in a number of dental and bone restorative procedures. Silicon's beneficial effects include promoting biological mineralization and bone formation. In this chapter's study, work silicon-doped (3% and 7%) nanometer-scale hydroxyapatite powders were synthesized using a combined ultrasonic and microwave heating-based method before being annealed at either 400 °C or 800 °C. Subsequent XRD pattern analysis revealed the silicon-doped hydroxyapatite powders had a crystalline nature. Increasing silicon content was found to inhibit grain growth and reduce crystallinity. X-ray peak broadening analysis revealed that increasing amounts of silicon in the hydroxyapatite lattice structure produced distortion that increased lattice constants, the unit cell volume, and lattice strain. Both FT-IR and EDS analysis techniques revealed (SiO4)4- ions were being substituted for (PO4)3- ions in the hydroxyapatite lattice structure. In addition, electron microscopy studies found the presence of silicon in the hydroxyapatite lattice structure inhibited grain growth. Image analysis also confirmed increasing silicon content reduced grain growth and influenced grain morphology.