‘Simultaneous technique’ and a hybrid microseal/pacmac obturation

Root canal preparation involves cleaning and shaping of the root canal system1 in order to eliminate infection and necrotic or inflamed pulp tissue2 and to prepare the root canal to receive a specific root-filling material.1 Because of their ability to shape root canals with fewer procedural errors, Nickel-Titanium (Ni-Ti) rotary instruments enhance the predictability of root canal preparation.2

Mtwo instruments have the following properties:

Their cross-sectional design is therefore comparable to the Quantec LX series.2

It is suggested that the standard Mtwo Ni-Ti rotary files (Sweden and Martina, Due Carrare, Padua, Italy and VDW, Munich, Germany) are used according to the ‘simultaneous technique’.4 This is a ‘crown-down’ preparation characterized by the fact that each instrument should be used to the full working length (WL),3,4 from smaller to larger size.4,5 Light pressure in an apical direction is required during instrumentation; if a binding sensation is experienced the instrument should be used 1–2 mm shorter than the maximum depth reached, in an anti-curvature brushing motion with an amplitude of around 5mm, to remove coronal interferences on the outstroke, prior to further progression. The standard sequence can be followed by the Mtwo apical finishing files (Mtwo A), if the proposed hybrid Microseal/PacMac obturation technique is chosen.