Temperature rise on the surface of NiTi and stainless steel fractured instruments during ultrasonic removal

• Published in: International endodontic journal 2015-09, Vol.48 (9), p.872-877
• Main Author: Madarati, A. A.
• Format: Article
• Language: English
• Subjects: complications; Dental Instruments; Dentistry; Equipment Failure; Foreign Bodies - therapy; fractured; Hot Temperature; Nickel; removal; separated; Stainless Steel; temperature; Titanium; Ultrasonic Therapy - adverse effects; Ultrasonic Therapy - instrumentation; ultrasonics
• ISSN: 0143-2885; 1365-2591
• DOI: 10.1111/iej.12383

Aim To investigate the temperature rise induced by ultrasonic tips when activated against two types of fragments at two power‐settings. Methodology Twenty‐four F2‐ProTaper Universal rotary files and 36 stainless steel K‐files, size 50, were sectioned at a point 5.5 mm from their tips. At specific power‐settings, ET40D ultrasonic tips were activated against the peripheral surface of the fragment coronal part (1 mm) for 30 s with/without Air‐Active function according to each group; (i) without Air‐Active function at power‐setting 1.5 against NiTi fragments, (ii) without Air‐Active function at power‐setting 1.5 against SS fragments, (iii) without Air‐Active function at power‐setting 3 against SS fragments, (iv) with Air‐Active function at power‐setting 3 against SS fragments, and (v) with Air‐Active at power‐setting 3 against NiTi fragments. Temperature rises were inspected at 15 and 30 s using the thermocouples. Results With no Air‐Active function and power‐setting 1.5, the temperature rises induced on NiTi fragments at 15 and 30 s (36.33 and 55.44 °C, respectively) were significantly greater than those induced on SS fragments at 15 and 30 s (26.08 and 35.27 °C, respectively) (P = 0.001 and