Micromorphometric analysis of bone blocks harvested with eight different ultrasonic and sonic devices for osseous surgery

OBJECTIVES: The aim of this study was to analyse in vitro the main features of osteotomies performed by means of different ultrasonic and sonic systems for bone surgery. MATERIALS AND METHODS: Six ultrasonic and two sonic devices for osseous surgery were evaluated during block harvesting on bovine bone. After measuring cutting speed, images of the blocks were acquired by light stereo-microscope and E-SEM, in order to measure the osteotomy thickness and to evaluate the presence of intra-trabecular bone debris and signs of thermal injuries on the bone. Roughness evaluation was performed using a profilometer. RESULTS: All the ultrasonic instruments required a shorter time than sonic systems to perform the block harvesting (p < 0.05). Piezomed was found to be the most efficient in terms of cutting speed (20.5 mm(2)/min), even if not significantly different from most of the devices here tested (p > 0.05). K-Bisonic and Variosurg 3 showed the smallest percentage variance between tip thickness and osteotomy width. Intra-trabecular debris was found to occur in inverse proportion with the width of the osteotomy: the tighter the track, the higher the amount of debris. Sonicflex Bone, Piezotome 2 and Sonosurgery showed almost no signs of thermal injuries on the osteotomised surfaces. CONCLUSIONS: No single ultrasonic or sonic device combined all the best features of speed, precision and bone micro-architecture preservation.