The Effect of Instrumentation with Two Different File Types, Each with 2.5% NaOCl Irrigation on the Microhardness of Root Dentin

• Published in: Journal of endodontics Vol. 28; no. 4; pp. 311 - 312
• Main Authors: Slutzky-Goldberg, Iris, Liberman, Reuven, Heling, Ilana
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2002
• Subjects: Analysis of Variance; Dental Alloys; Dentin - drug effects; Dentin - ultrastructure; Dentistry; Disinfectants - therapeutic use; Equipment Design; Hardness; Humans; Nickel; Pulpectomy - instrumentation; Root Canal Irrigants - therapeutic use; Root Canal Preparation - instrumentation; Rotation; Sodium Hypochlorite - therapeutic use; Stainless Steel; Statistics as Topic; Time Factors; Titanium; Tooth Root - drug effects; Tooth Root - ultrastructure
• ISSN: 0099-2399; 1878-3554
• DOI: 10.1097/00004770-200204000-00012

The aim of this study was to measure root-dentin microhardness after instrumentation with two types of files and using irrigation with 2.5% sodium hypochlorite. Thirty roots were instrumented with irrigation: 10 roots had the pulp extirpated only; 10 roots were instrumented with stainless steel files, and 10 roots were instrumented with rotary nickel-titanium (NiTi) files. Additionally, five roots were extirpated only without irrigation and served as a control. The roots were sliced and root-dentin microhardness was determined at depths of 500 μm and 1000 μm from the pulp-dentin interface. Significant differences were found between the microhardness at 500 μm and 1000 μm (p < 0.001) in all groups. Instrumentation with NiTi rotary files affected dentin microhardness significantly to a lesser extent.