J Conserv Dent Endod. 2024 Jun;27(6):603-607. doi: 10.4103/JCDE.JCDE_158_24. Epub 2024 Jun 6.
ABSTRACT
CONTEXT: To improve efficiency, biomechanical preparation in root canal treatment is shifting from manual SS to nickel-titanium (NiTi) rotary devices. While multi-file NiTi systems entail crack and fracture issues, modern single-file systems address these concerns.
AIMS: The aim of this study was to evaluate and compare the effects of different torque settings on dentinal crack formation using single-file systems (SFS) (One Curve [OC]) and multi-file systems (ProTaper Next [PTN]) at different levels of the tooth.
SUBJECTS AND METHODS: The study was conducted on 45 freshly extracted human mandibular premolars divided into groups: OC at minimal and maximal torque, PTN at minimal and maximal torque, and a control group. After canal preparation, teeth were horizontally sectioned at 3, 6, and 9 mm from the apex, and then examined for cracks using a stereomicroscope.
STATISTICAL ANALYSIS USED: This was analyzed using Chi-square test.
RESULTS: PTN group: Highest crack rates at the middle (55.6%) and apical (77.8%) thirds with maximum torque; OC group: Highest rates at the middle (22.2%) with minimal torque and apical (11.1%) with maximum torque.
CONCLUSIONS: Maximal torque settings had more incidence of cracks compared to minimal torque settings. It can be stated that SFS (OC) produced less cracks compared to multi-file system (PTN) at both minimal and maximal torque settings.
PMID:38989499 | PMC:PMC11232774 | DOI:10.4103/JCDE.JCDE_158_24