Morphological studies on structual changes of root canal wall after instrumented by files and irradiated by argon laser

Abstract

Abstract : The effective shaping of root canal wall with following the tortuous canal is very important. Therefore, many new instruments and machines have been developed up to now.

 The purpose of this study was to observe the morphological changes of the canal wall after instrumentation with conventional stainless steel files and nickel-titanium files that come to be used recently and furthermore to investigate the possibility of the enlargement with Argon Laser irradiation. 44 extracted maxillary molars were instrumented by Mac File (NiTi Co.) and K File (Kerr Co.) with alternative irrigation of 8% NaOCl and 3% H₂O₂. Argon Laser (λ=514 nm, 1W or 2W, CW : HGM Co.) was irradiated on the root canal wall with fiber. The morphological changes of the canal wall was observed by a stereomicroscope and a scanning electric microscope after making the vertical slice. The scores of debris were statistically evaluated using the Mann-Whitney U test.

 We observed that there was no remarkable difference between the morphological changes of the canal wall after instrumented with NiTi files and those of SS files. However, NiTi files removed more efficiently intracanal debris than SS files. And Argon Laser irradiation accelerated to remove intracanal debris effectively.