Clinical indications, advantages and limits of the expansion-condensing osteotomes technique for the creation of implant bed.

The "screw shaped" expansion-condenser are hand instruments that were introduced for the first time at the end of the 70' in order to improve bone density before the positioning of a dental implant. Thanks to these hand instruments it is possibile to compact the bone apically and along the walls of the implant bed (Fig. 3) improving a lot the bone density and the primary stability of the implant even in situations where the starting bone quality is low (es. D3-D4 as in the classification y Lekholm and Zarb 1985) or in cases of severe bone atrophy. Allowing a manageable raising of the shnaiderian membrane through trans-alveolar way, this technique avoids in many cases the necessity to have recourse to the realisation of bone vestibular "gates" when it comes to the techniques of the big sinus lift. The knoledge of the bone visco-elastic and hystologic properties together with the maximum respect of the surgical protocol allows us to obtein % of success superior than traditional surgical protocol in D3-D4 bone class.