DTUK1910

July 19-25, 201014 Endo Tribune United Kingdom Edition and a micro cannula to remove gross debris and fine canal de- bris; that has been flushed from the canal by the action of pulling irrigants down the canal as they are simultaneous expressed in the pulp chamber with a syringe. In any event, ultrasonic and negative pressure irrigation has been shown to provide a statis- tically significant improvement in canal cleanliness, especially when compared to passive sy- ringe irrigation. FAQ: Can I use TF with any com- mercially available electric motor? TF can be used with any electric motor. What is optimal rotational speed for TF? 500-900 rpm. Do I need to use torque control? Using torque control is a matter of personal preference. Can TF be used for retreat- ment? Yes, TF can be used to remove gutta percha and can grind out the plastic of carrier-based sys- tems if the action is performed correctly. How do I obturate TF prepa- rations? What master cones do I use and how do I match my preparations with these master cones? TF preparations are obturated exactly as any other prepara- tions. I use bonded obturation in the form of RealSeal* Master Cones and RealSeal One Bond- ed obturators*. When using the master cones, I trim the .06/20 RealSeal Master cones and downpack them with the Sys- temB technique via the Elements Obturation unit*. If for example the master apical diameter is an ISO tip size #50 preparation, five mm are trimmed from the end of the .06/20 master cone to provide a master cone with an tip diameter of .5 mm. RealSeal has been shown in in-vitro and in vivo studies to reduce coronal leakage across the totality of the canal relative to gutta percha. How does the use of TF differ from other RNT files? Are not all RNT files the same? In many canal anatomies, the entire preparation can be made with one single file, the .08/25 TF if the master apical diameter chosen is a #25. In more com- plex anatomies, the .06/25 may also be needed to prepare the basic taper. As mentioned above, these files are introduced crown down, from larger tapers and tip sizes to smaller to prepare the basic taper of the canal. Once the basic taper is prepared, the master apical diameter can be enhanced. If, for example, the clinician were preparing a #50 master apical diameter the clini- cian would prepare the master apical diameter with the .06/30, .06/35, .04/40 and .04/50 TF in succession. The insertion of these additional files to enhance the master apical diameter oc- curs with one insertion of each of the instruments after the basic preparation is made. TF can prepare larger tapers more rapidly with fewer files and fewer insertions than files manufactured by a traditional grinding process. Routinely, this means that for an average molar tooth, the final prepared taper will be .08 and the master apical diameter is easily prepared as described above. A .08 taper can be prepared with one .08/25 TF file in approximately 75 per cent of the clinical cases encountered, with the .08/25 and .06/25 in 20 per cent of clinical cases encoun- tered and the .08/25, .06/25 and .04/25 in five per cent of clini- cal cases encountered. In the creation of the basic taper, each file needs usually no more than three-four insertions to reach the TWL. As mentioned above, the preparation of the master apical diameter is performed with one insertion of each of the instru- ments designed for this purpose (.06/30, .06/35, .04/40 and .04/50 TF). How important is it to have a glide path? TF is not to be used without first assuring patency, preparing a glide path and/or without lubri- cation. Using the M4 Safety hand piece attachment, reciprocating the #10 HKF provides the initial minimal diameter of a #15 HKF. In essence, once the #10 HKF is reciprocated, the canal is ready for TF preparation. Can TF be blended with other RNT systems? Yes, but there is no reason for incorporating other files into the TF technique. TF is an independ- ent system. For many canals, as described, a single TF file can prepare the entire canal if the glide path is prepared correctly. This article has described a new RNT file manufactured by twisting NT while in the rhom- bohedral crystalline phase con- figuration. Emphasis has been placed on glide path creation, copious irrigation, lighting and magnification as well as the ef- ficiency, safety and predictability of TF canal preparation as evi- denced by the increased tapers, master apical diameters as well as fewer insertions and files needed for canal preparation. I welcome your feedback. DT *SybronEndo (Orange, CA, USA) Fig 3: RealSeal One Bonded Obturators* Fig 5: The M4 Safety Handpiece* Fig 4: The Twisted File* page 13DTß About the author Dr. Mounce is the author of the non- fiction book Dead Stuck, “one man’s stories of adventure, parenting, and marriage told without heaping plati- tudes of political correctness.” Pacific Sky Publishing. DeadStuck.com. Dr. Mounce lectures globally and is widely published. He is in private practice in Endodontics in Vancouver, WA, USA. ‘Ultrasonic and negative pressure irrigation has been shown to provide a statistically signifi- cant improvement in canal cleanliness, especially when compared to passive syringe irrigation.’