Comparative analysis of pericervical dentin reduction using three rotary file systems: A micro-computed tomography study

Abstract

Background: Maintaining pericervical dentin (PCD) thickness is crucial for the long-term prognosis of endodontically treated teeth. Root fractures are closely linked to PCD loss, which is influenced by the type of rotary file system used. Aims: This study compared the effect of three rotary file systems – TruNatomy, OneShape, and ProTaper Gold – on PCD thickness in the mesiobuccal root of mandibular molars using micro-computed tomography (micro-CT). Materials and Methods: Twenty-seven mandibular first molars were mounted on wax and scanned using micro-CT before and after instrumentation. Samples were randomly divided into three groups (n = 9) and instrumented per manufacturer guidelines. PCD thickness was measured at 2 mm and 4 mm below the cementoenamel junction (CEJ) on mesial, distal, buccal, and lingual surfaces. Data were analyzed using a paired t-test, one-way analysis of variance, and Tukey’s post hoc test (P < 0.05). Results: No significant difference was observed at 4 mm below the CEJ. However, TruNatomy showed significantly less dentin removal at 2 mm (P = 0.003). Conclusions: TruNatomy preserved the most dentin, followed by ProTaper Gold and OneShape. Selecting appropriate rotary instruments can help minimize dentin loss and enhance the longevity of endodontically treated teeth.