The multiscale characterisation of high intensity focused ultrasound (HIFU) on the dentin substrate

This study investigates the use of both concave and flat-surface HIFU transducers operated in pulsed mode as an acid-free method of dentin smear layer removal. Ultrasound based smear layer conditioning removes the obstructive smear layer, enhancing self-etch mode universal adhesive interaction with the dentin surface whilst simultaneously preserving the mineral content of dentin to optimise chemical bonding of functional monomers. Additionally, the thermal tests have been conducted to ensure biocompatibility with dental pulp stem cells, with no significantly deleterious effected of ultrasound conditioning observed.