Abstract
Objectives The purpose of this study was to evaluate the thermal stability of 23 commercially-available endodontic obturation materials. Materials and methods Specimens (n = 10) were sealed in aluminum differential scanning calorimetry (DSC) crucibles and subjected to thermal scan series consisting of a 25 to 70 °C at 5 °C/min followed by a rapid increase to 230 °C, followed by a second scan from 25 to 70 °C at 5 °C/min. The first scan evaluated the materials as-received followed by a worse-casescenario thermal challenge simulating temperatures involved with warm vertical condensation obturation techniques. The second thermal scan observed any phase changes from the high temperature challenge. This two-scan process was repeated twice to observe changes encountered by repeat high heat exposure during obturation. Mean thermal enthalpies were analyzed with Kruskal-Wallis and Games-Howell posthoc test. (p = 0.05). Results Thermal behavior was material dependent. During the first thermal scan, materials typically demonstrated broad endothermic enthalpy curves suggesting either a gutta-perchaphase mixture and/or an alpha crystalline phase. The first high-heat challenge produced definitive alpha/beta thermal phase signatures usually associated with gutta-percha. Changes in beta-phase enthalpies were noted with Therarmafil Plus and UltraFil Firmset while increase in alpha-phases was observed with GuttaCore, K3, Lexicon, and Schein Accessory Points. Conclusions Commercial endodontic gutta-percha obturation materials displayed thermal characteristics that were material dependent. However, all demonstrated stability at temperatures in excess to that experienced during warm vertical condensation techniques. Clinical relevance The gutta-percha obturation materials evaluated in this evaluation can be used successfully in warm vertical condensation techniques without fear of degradation.
Original language | English |
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Pages (from-to) | 2589-2602 |
Number of pages | 14 |
Journal | Clinical Oral Investigations |
Volume | 21 |
Issue number | 8 |
DOIs | |
State | Published - Nov 2017 |
Bibliographical note
Publisher Copyright:© Springer-Verlag Berlin Heidelberg (outside the USA) 2017.
Keywords
- Differential scanning calorimetry (DSC)
- Gutta-percha
- Thermal analysis
- Thermal stability
ASJC Scopus subject areas
- General Dentistry