The aim of this study was to compare the results obtained using an electrothermal bipolar vessel sealing system (Ligasure Precise), a harmonic curved shears (Harmonic Focus) and traditional technique in total thyroidectomy. We have enrolled 93 patients and assigned randomly to three groups of 31 pt: groups L (Ligasure Precise), F (Harmonic Focus) and C (traditional thecnique). Recorded data were demographics, preoperative serum calcium levels, operation time, length of hospital stay, weight of exported gland and pathology, postoperative calcemia at one and two days and recurrent laryngeal nerve paralysis. The three groups did not present statistically significant differences in term of age, gender and pathology classification. No postoperative haemorrhages were observed. The overall incidence of hypocalcemia was 38.9% (36 pt) and the mean days of hospitalization were 2.3 days without statistically significant differences between the three groups. Only one patient (group F) presented temporary recurrent laryngeal nerve paralysis. Mean operation time (minutes) was significantly reduced by approximately 15% in group F (62.7+/-14.1) compared with group C (72.7+/-13.6; Kruskal-Wallis test: p<0.05). Both devices resulted safe and efficient. The only advantage observed was a significant reduction operation time when using Harmonic Foscus curved shears compared to the other techniques.