Effect of Autoclave on Surface Topography of Various Rotary Files

Rotary files are essential tools in endodontic procedures, designed to efficiently shape and clean the root canals. However, repeated sterilization, particularly via autoclaving, may affect their surface integrity, potentially compromising their performance and longevity. This study aims to evaluate the changes in surface topography of various rotary files after multiple autoclave cycles using Scanning Electron Microscopy (SEM).

In this study, three types of rotary files-NiTi, stainless steel, and gold-treated files-were selected for analysis. Each type comprised 20 samples, totaling 60 files. The files underwent 10 cycles of autoclave sterilization at 121°C for 15 minutes. SEM analysis was conducted before and after sterilization to assess changes in surface characteristics. Parameters such as surface roughness, presence of micro-cracks, and debris retention were meticulously evaluated.

Post-autoclave SEM analysis revealed significant alterations in surface topography across all file types. NiTi files showed an increase in surface roughness by 35%, with evident micro-cracks in 40% of samples. Stainless steel files exhibited a 25% increase in surface roughness, while 30% showed minor deformities. Gold-treated files displayed the least surface alteration, with a 15% increase in roughness and micro-cracks observed in only 10% of samples. Debris retention was notably higher in NiTi files post-sterilization.

Autoclave sterilization significantly impacts the surface topography of rotary files, with NiTi files showing the most pronounced changes. Gold-treated files exhibited greater resistance to topographical alterations, suggesting superior durability under repeated autoclave conditions. These findings underscore the importance of selecting appropriate file types based on sterilization frequency to ensure optimal endodontic performance and tool longevity.