A Novel technique to synthesize next generation bioactive dental fillers

Objectives: Recently microwave technology has evolved as emerging method in biomaterial synthesis and fabrication. This present novel study optimized the wet precipitation synthesis of ceramic particles in terms of shortest time span of exposure to microwaves with intense power of radiation. In addition, effect of power input and exposure time was analyzed on synthesis at high temperatures. Methods: Calcium-phosphate precursor solutions were mixed while continuous agitation followed by exposure to microwaves for varying time (1-10min) and power inputs (600-1000W). Various reinforcements (CNT,TiO₂,Al₂O₃) were added to apatite by same methodology. Powders have been analyzed for structural [Fourier Transform Infrared Spectroscopy (FTIR)], phase purity [X-ray Diffraction (XRD)], and particle size and morphology [Scanning Electron Microscopy, Energy Dispersive Spectroscopy (SEM,EDS) characterizations. Results: Characteristic functional groups were confirmed by FTIR for both native particles and composites. Calcium-phosphate ratio was found to be 1.5-1.7 by EDS analysis. XRD revealed the presence of required calcium-phosphate phases in desired ratios and resulting materials were thermally stable at 1200°C. SEM images showed spherical morphology and effect of varying parameters on particle size and morphology (ranging from micro to nano-scale). Conclusion: Microwave radiations have proved a potential energy source to synthesize particles with desired tailored features. Exposure to microwaves accelerates the reaction kinetics leading to the uniform and rapid nucleation of crystals in reaction mixture. Such conditions facilitate the evolution of phase pure product and each of these has its own potential characteristics to be used in a biomedical and dental application.