Comparative evaluation of pediatric rotary file systems and hand files for root canal preparation in primary molars: an in vitro study

Background: The purpose of the study was to compare pediatric rotary files with hand K-files regarding the amount of dentin removal, root canal transportation, root canal surface area and volume in primary mandibular second molars using Cone-Beam Computed Tomography (CBCT). Methods: A total of 36 primary teeth were randomly divided into four groups; K-file, Fanta AF Baby file, EndoArt Ni-Ti Pedo file Gold Kit, MiniSCOPE Ni-Ti Gold Pediatric file. Samples were imaged with CBCT before and after canal instrumentation. For root canal surface area and volume measurements, 3-Matic (Materialize, Belgium) software was used. Linear measurements were performed using NNT iRYS software. Data analysis was conducted using the Dunn’s test and the Kruskal Wallis test. A significance level of p < 0.05 was used. Results: Compared to pediatric rotary files, the K-file was shown to remove a statistically greater amount of dentin at the coronal level (p = 0.032). The difference in dentin thickness with the K-file was significantly greater than with the EndoArt file (p = 0.017) and the MiniSCOPE file (p = 0.007). The volume difference with the MiniSCOPE file was significantly less than with the Fanta file (p = 0.002) and the EndoArt file (p = 0.032). Root canal transportation was significantly greater with the K-file compared to the Fanta AF Baby file in both the oblique (p = 0.031) and buccal-lingual (p = 0.006) directions. Conclusions: Pediatric rotary files could be considered an efficient alternative to the hand K-file in biomechanical instrumentation. Three dimensional analysis can provide better comprehensive approach to evaluating the pediatric rotary instruments.

Primary teeth; Root canal preparation; Cone-beam computed tomography; Endodontics

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