Análise dimensional e da superfície de limas endodônticas manuais tipo K

Abstract

This study aims to evaluate five different brands (TDK®, Dentsply®, Injecta®, MK Life®, and Bassi®) that market manual K-type endodontic files, in terms of compliance with ISO (International Standardization for Organization) standards, by analyzing five specific characteristics: tip diameter, diameter at 1 mm from the tip (D1), length of the active part, surface quality, and quality of the active tip. Thirty new endodontic instruments were evaluated, with six files from each manufacturer, ranging from specification 1 to the series. The instruments were removed from their packaging and evaluated using SEM (Scanning Electron Microscopy) at magnifications of 100x and 250x, and a clinical operating microscope at 6.8x. All photomicrographs were measured with the ImageJ program for comparison to the ISO standard, and the SEM images underwent analysis by three evaluators to classify them on a score scale from 0 to 3. There was a significant statistical difference in the diameter measurements between the different brands analyzed, with deviations from the standard exceeding ±0.02 mm. Regarding the surface quality scores, group 2 (Dentsply®) showed a significant difference from the other groups with a final score of 0, and regarding the quality of the active tip, there was a significant statistical difference between the groups. The results are relevant for the assessment of the quality and reliability of the brands, suggesting the need for adjustments in manufacturing requirements to ensure full compliance with the required specifications. The different brands do not fully follow the ISO standard, with some manufacturers exceeding the tolerance limit for the observed measurements and showing poor performance regarding surface quality and tip quality.