Robert Milad ¹*, Ahmed Ghobashy ² and Khaled Ezzat³

¹Department of Child Dental Health, Faculty of Dental Sciences, Lagos University Teaching Hospital, Nigeria
²Department of Child Dental Health, Faculty of Dental Sciences, CMUL/Lagos University Teaching Hospital, Nigeria

*Corresponding Author: Robert Milad William Moussa, B.D.S, Faculty of Oral and Dental Medicine, Misr International University, Egypt.

Received: March 04, 2025; Published: March 19, 2025

Abstract

Aim: The aim of the study was to evaluate the fracture resistance of mandibular molar mesial roots following the removal of separated endodontic instruments using traditional and conservative approaches to identify the more conservative technique in terms of maintaining root strength.

Methodology: Twelve extracted mandibular first molars with separate mesial canals were instrumented, and files were intentionally fractured within the canals. Teeth were divided into three groups (n=4 per group): file retrieval using traditional technique with 0.25mm diameter ultrasonic tips (ET25), Traditional technique with 0.40mm diameter ultrasonic tips (ET40), and conservative technique using TFRK ultrasonic tips. Specifically, ET25 ultrasonic tips were 20 mm in length, possessed a 3% taper, and were fabricated from titanium-niobium alloy, while ET40 ultrasonic tips were 40 mm in length, featured a 4% taper, and were made from stainless steel. File retrieval attempts were limited to 60 minutes. Subsequent to the retrieval attempts, the fracture resistance of the remaining tooth structure was tested after instrumentation.

Results: There was a statistically significant difference in maximum load (Newtons) among the groups (p < 0.002). The conservative technique group (Median=1328.45 N) exhibited significantly higher fracture resistance compared to the traditional ET25 group (Median=1031 N) and the traditional ET40 group (Median=700.19 N) (p < 0.05).

Conclusion: Within the limitations of the study, it was concluded that the conservative technique is a more conservative approach for file retrieval in mandibular molars, preserving greater root strength and potentially reducing the risk of root fracture, thereby improving long-term tooth prognosis.

Keywords:Ruddle Technique; Terauchi Technique; Separated Instruments; Fracture Resistance; Mandibular Molars

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Citation

Citation: Robert Milad., et al. “Evaluation of Fracture Resistance in Mandibular Molars’ Mesial Roots After Removal of Separated Instruments Using Traditional and Conservative Techniques: In-vitro Study". Acta Scientific Dental Sciences 9.4 (2025): 75-83.

Copyright

Copyright: © 2025 Robert Milad., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.