Although the harmonic scalpel has been shown to be safe and effective in thyroid surgery, several surgeons consider the previously available instruments to be large and cumbersome, especially in terms of tissue fine grasping and dissection capabilities. To this context, an innovative technical improvement of the device for thyroid surgery has very recently been implemented and has been made available in 2008. Utilization of this new device, however, has not been evaluated in any study. The objective of this prospective randomized study is to compare the results of total thyroidectomy using the new harmonic scalpel device (FOCUS) to that with the previously available harmonic scalpel device (HARMONIC ACE) in respect to hemostasis, operative time and postoperative complications. All patients submitted to total thyroidectomy are randomized into two groups: those submitted to total thyroidectomy using the FOCUS device (group Α) and those with HARMONIC ACE (group Β).