-To determine the influence of the number of files in the extrusion of debris as an aetiological factor of symptomatic apical periodontitis and its relation with the biological events that trigger the postoperative inflammation of the periodontal ligament.
- An extensive literature research was carried out in the Medline, ISI Web of Science and Cochrane databases.
- 2 reviewers independently rated the qualityofeach study determining the level of evidence ofthe articlesselected.
- The primaryoutwrne for the was determined by the amountofdebris extruded into the periapical tissue during root canal preparation with multiple- or single-file systems in four laboratory studies.
- Analysis of in vivo release of neuropeptides (SP and CGRP) after root anal preparation with single- or multiple-file systerns was also carried out.
Most highlighted Results:
- A total of 11 articles were included in the systematic review: two clinical studies and 9 laboratory studies
- all root canal preparation systems were associated with debris extrusion, with single-file preparation extruding greater amounts when compared to multiple-file
- The cross section of the file was found to be the most important feature in the design of the instruments that affected debris extrusion.
- rotary-file systems (ProTaper Universal and Mtwo) tended to cause less debris extrusion than the single-fik instruments (WaveOne and Reciproc), this difference was significant.
- increased expression of SP and CGRP with the use of ProTaper Universal and WaveOne sptems, when compared to Mtwo and Reciproc.
- Analysis of neuropeptide expression suggests that the design of the instrument is more important than the number of files used.
rotary-file system, generate apical extrusion of debris and expression of neurope*ides. The inflammatory reaction is not influenced by the number of files but the type of movement and instrument desW1.