BACKGROUND Specific complications after thyroid surgery, such as recurrent laryngeal nerve injury (RLN) or hypoparathyroidism, are feared because they may give rise to a lifelong disability for the patient. The aim of this study was to evaluate the possible association between the types of device used (bipolar vs ultrasound-based harmonic scalpel defined Harmonic Focus) and major postoperative complications. METHODS During a 1-year period, between October 2010 and October 2011, Italian Endocrine Surgery Units affiliated with the Italian Endocrine Surgery Units Association collected data on all consecutive patients older than 18 years who had undergone primary total thyroidectomy, near total thyroidectomy, and completion thyroidectomy. The data were included in a dataset, listing demographic variables, details on the surgical procedure, and 2 major complications of the thyroid surgery: postoperative RLN palsy/hypomobility and hypocalcemia. RESULTS Our population comprised 1,846 subjects (78.6% women, median age 52 years). Six hundred four (32.7%) subjects underwent thyroidectomy by bipolar forceps and 1,242 (67.3%) by ultrasonic device. The risk of hypocalcemia in subjects undergoing thyroidectomy by ultrasonic device was similar to those undergoing thyroidectomy by bipolar after adjusting for sex, type of thyroidectomy, and central lymphadenectomy (odds ratio .94, 95% confidence interval .76 to 1.17). Subjects who underwent thyroidectomy by ultrasonic device had a lower risk of RLN paralysis compared with those undergoing thyroidectomy by bipolar forceps also after adjusting for central lymphadenectomy (odds ratio .39, 95% confidence interval .2 to .7). CONCLUSION This multicenter study acknowledges the value of the ultrasonic device as a protective factor only for RLN palsy, confirming nodal dissection as a risk factor for postoperative hypocalcemia and vocal folds disorders.