THE MICROMORPHOLOGICAL RESEARCH OF THE INTERNAL STRUCTURE OF CHAIRSIDE CAD/CAM MATERIALS BY THE METHOD OF SCANNING IMPULSE ACOUSTIC MICROSCOPY (SIAM) Article Goryainova K.E., Morokov E.S., Retinskaja M.V., Rusanov F.S., Apresyan S.V., Lebedenko I.Y. Open Dentistry Journal. Bentham Science Publishers B.V.. Vol. 12. 2018. P. 125-132