RO0111

36 I I clinical technique _ R-phase 1. in order to avoid a taper lock, which can lead to file separation or damage in severely curved canals; and 2. in order to avoid a strip perforation caused by aggression of the files. We must carefully analyse the preoperative X-ray to determine the location of the curve. This can be achieved by inserting a size 10 K-file, which will take the impression of the canal. It gives us a good idea of the curve or curves, as well as the shape of the canal, thereby helping us determine a strategy regarding the depth to which we can go with our large files and thenswitchtoalessertaper.Thisisasimpleclinicaltip that is helpful in avoiding serious complications in shaping curved canals. ThesequenceIpersonallyfollowwithTwistedFiles (TF; SybronEndo) is as follows. After checking root- canal patency and taking the impression of the canal withasize10K-file,IusemyM4handpiecewithasize 20 SS file for 15 seconds in each canal (Fig. 7). It does nothavetogotolength.Ionlytakeitasdeepasitwill go with a simple push and pull movement and use sizes 15 and 10 SS files, if required, after the size 20 in a crown-down method. After achieving patency, I use the rotary files in order to clean and shape the root-canal system. I start with a size 25 with taper 0.08, taking it to the beginning of the curve. I limit its insertion to this point. I then usually switch to a size 25TFwithtaper0.06,dependingontheseverityofthe curve. If the curve is normal to medium, a size 25 TF with taper 0.06 should be able to enlarge it safely. If the curve is severe, which will show on the size 10 K- files and from the resistance of the previous file, I use asize25TFwithtaper0.04tofullworkinglength.The apical enlargement will follow the crown-down, which has opened a safe way to the apical area, or the last 3 mm for enlargement. I use a size 40 TF with taper0.04wheneverIamabletoforoptimalcleaning of the apical area, as well as for reducing the colony formationunitandpreparingthedentineforobtura- tionusingRealSeal(SybronEndo)accordingtoproper irrigation protocol. Achieving step-by-step root-canal preparation is the gold standard of care that we can offer to our patients without any negative surprises along the way. Respecting a few simple rules and not letting ourselves be carried away by our temptation to work more quickly can lead to excellent clinical results. I would like to thank Yulia Vorobyeva, interpreter and translator, for her help with this article._ roots1_2011 Ass.Prof.Philippe Sleiman Dubai Sky Clinic Burjuman BusinessTower,Level 21 Trade Center Street,Bur Dubai Dubai,UAE phil2sleiman@hotmail.com _contact roots Figs. 8–11_Clinical cases. Fig. 8 Fig. 9 Fig. 10 Fig. 11