The Influence of a Glide Path on the Lifespan of WaveOne Reciprocating Files

摘要

Background: Nickel-titanium instrument separation is a serious concern in endodontic therapy. A significant reduction of rotary instrument separation could be obtained when use of rotary file is anticipated by an initial manual preflaring and glide path. Normally this procedure is carried out by stainless steel hand files but new rotary nickel-titanium instruments (PathFiles) for mechanical glide path has been recently introduced. Methodology/Principal Findings: Canal preparation was performed on 100 Endo-Training Block simulators divided in two equal groups, depending on the used technique (with and without a glide path). Average lifespan and cumulative survival at the time of WaveOne (Dentsply Maillefer) files before and after the creation of a glide path with PathFiles (Dentsply Maillefer) were tested. Following the instructions of the producer all the files were operated using The WaveOne? Endodontic system (Dentsply Maillefer). All WaveOne files worked till fracture occurred. During mechanical instrumentation each file was coated with Glyde? (Dentsply Maillefer) to act as a lubricant, and copious irrigation with 5.25% NaOCl was carried out. Eight WaveOne reciprocating files were used in canals’ preparation and six of them broke: 4 files before the creation of a glide path and 2 after the initial enlargement of the canals with PathFile system. The average lifespan of one WaveOne file without a creation of a glide path was 10.25±2.50 canals and after a creation of a glide path – 17.50±2.12 canals. The difference was statistically significant (p<0.05). The instruments used after a glide path was created presented a significantly longer survival at the time (р<0.05). Conclusions: Within the limits of this study, NiTi rotary Path Files appear to be suitable instruments for safe and easy creation of the glide path before use of WaveOne reciprocating files. The initial enlargement of the canals increases significantly the average lifespan and the survival rate of WaveOne files.